School Nutrition

School Nutrition,

A school meal is a meal (usually lunch or dinner) provided to students at a school. It is usually served at sometime around noon; however, many also serve breakfast before classes begin in the mornings. The purpose is to ensure the proper nutrition and health of children, so that they may learn more effectively.

Some schools have theme days whereby food is served in a particular style. For example, the school might serve Chinese cuisine to celebrate the Chinese New Year. There may also be weekly recurring themes, such as "Taco Tuesdays", "Macaroni Mondays," or pizza at the end of the week.

School Nutrition by country

Canada

Canada has no national school meal program, and elementary schools are usually not equipped with kitchen facilities. Parents are generally expected to provide a packed lunch for their child to take to school, or have their child return home for the duration of the lunch period.

However, some non-profit organisations dedicated to student nutrition programs do exist.

Finland

Free school dinners in elementary and secondary schools have been served nationwide since October 9, 1948. In some cities poor people were offered free school dinners from the beginning of the 20th century (eg. from 1902 in Kuopio, extending to all students in 1945).

In Finland also the lunches in Higher Education are subsidized. The Social Insurance Institution of Finland compensates 0,67 euros per student's daily meal. The meals served are to be as healthy and nutritionally balanced as possible.

Special diets based on religious, cultural or ethical choices or restrictions due to allergies are served with no extra cost.

India,

Mid-day Meal Scheme,

Under the Integrated Child Development Services (ICDS), government schools and partially-aided schools, along with Anganwadis, provide mid-day meals to the students attending such institutions, known as the Mid-day Meal Scheme. The meals served are free of cost and meet guidelines that have been set by the policy. The history of the program can be traced to 1925, making it one of the oldest free food programs for school children.

A single afternoon lunch usually contains a cereal which is locally available, made in a way acceptable to the prevailing local customs. Vegetables cooked as curry or soups and a portion of milk is allotted for each child. The menu is occasionally varied to appeal to students.

]Japan

In Japan, 99% of elementary school students and 82% of junior high school students eat kyūshoku, or school lunch.Parents pay 250 to 300 yen per student for the cost of the ingredients, with labour costs being funded by local authorities. The tradition started in the early 20th century. After the war – which brought near-famine conditions to Japan – the provision of school lunches was re-introduced in urban areas, initially with skimmed milk powder and later flour donated by an American charity. School lunch was extended to all elementary schools in Japan in 1952 and, with the enactment of the School Lunch Law, to junior high schools in 1954.

Usually, all meals provided on a given day are identical for all pupils of a Japanese school. The menu is planned by dieticians and changes daily. The average menu has gone through a large deal of change since the basic meals of the 1950s, as Japan grew economically.

School lunches were traditionally based on bread or bread roll, bottled or cartoned milk (introduced from 1958 to replace milk powder), a dessert, and a dish which changed daily. Popular dishes from the early days included inexpensive protein sources, such as stewed bean dishes and fried white fish. Whale meat, another cheap protein, was common until the 1970s. Provisions of rice were introduced in 1976, following a surplus of (government-distributed) Japanese rice, and became increasingly frequent during the 1980s. Hamburg steak, stew and Japanese curry became staples as well. Today, school lunches are a diverse affair, including soup and side dishes. Dishes range from Asian dishes such as naengmyeon, tom yam and ma po tofu to western dishes such as spaghetti, stew and clam chowder.

Sweden

School dinner has been free in Swedish elementary and secondary schools since 1993. Normally, the lunch is prepared like a buffet, where pupils serve themselves as much as they want (mainly potatoes/rice, meat/fish and vegetables). Milk and water are usually offered as drinks.

Singapore

School meals in most primary and secondary schools, and junior colleges, are provided in each school's canteen (or tuckshop). The canteens are made up of a number of stalls selling a variety of cuisine as well as beverages. Meals in the school canteens are of a lower price compared to similar meals in public food centres in Singapore.

United Kingdom

In the UK, school meals were first introduced in the 1870s to combat the high levels of malnutrition amongst children in poor areas. In 1944 it was made compulsory for local authorities to provide school dinners, with legal nutritional requirements. Free school meals were available to children with families on very low incomes.

As a result, staple traditional "school dinner" foods became embedded in the national psyche from the 1950s onwards. "School puddings" in particular refers to desserts traditionally (historically) served with school dinners, in both state schools and private schools. Examples include tarts such as gypsy tart and Manchester tart and hot puddings such as spotted dick and treacle sponge pudding.

In the 1980s Margaret Thatcher's Conservative government ended entitlement to free meals for thousands of children, and obliged local authorities to open up provision of school meals to competitive tender. This was intended to reduce the cost of local-authority-provided school meals, but caused an enormous drop in the standard of food being fed to children. A 1999 survey by the Medical Research Council suggested that despite rationing, children in 1950 had healthier diets than their counterparts in the 1990s, with more nutrients and lower levels of fat and sugar.

This became a major topic of debate in 2004 when chef Jamie Oliver spearheaded a campaign to improve the quality of school meals. School dinners at state schools are usually made by outside caterers whose incentive is increasing their profits. Since many of the requirements for nutritional content were removed in the 1980s, there is little reason for caterers to sell anything other than cheap, profitable, low quality food, particularly deep-fried fast-food like chips.

After a television documentary was shown on Channel 4 (Jamie's School Dinners), the public showed support for the increase of funding for school meals, causing the government to create the School Food Trust. The topic became a factor in the 2005 UK general election.

United States

Some school meal programs existed in the United States at least as far back as 1899, when Principal Arthur Burch of South Division High School in Milwaukee was granted permission to open a lunch room in the building. A basement room 27 by 60 feet was selected for the purpose; a kitchen 10 by 20 feet was partitioned off in one corner; furniture, dishes, etc. were purchased (for $316.65), and Emma Stiles of Chicago was placed in charge, to purchase provisions, plan each day's menu, and to see that all lunches were paid for. The menu was posted on a blackboard in the corridor, with each dish priced at five cents. This was something in the nature of an innovation and other cities made inquiries regarding the success of the scheme. The principal advantage, according to Burch's report to the Superintendent, was derived from serving warm lunches to the students, many of whom came from a distance too great to go home every day for a warm lunch, and who did better work in the afternoons than if they had eaten a cold one.

The National School Lunch Program was created in 1946 when President Truman signed the National School Lunch Act into law. The National School Lunch Program is a federal nutrition assistance program operating in over 101,000 public and non-profit private schools and residential care institutions. Regulated and administered at the federal level by the Food and Nutrition Service of the United States Department of Agriculture (USDA), it currently provides nutritionally balanced, low-cost or free lunches to more than 30 million U.S. children each school day. In its 60-year history, the program has expanded to include the School Breakfast Program, Snack Program, Child and Adult Care Feeding Program and the Summer Food Service Program. At the State level, the National School Lunch Program is usually administered by State education agencies, who operate the program through agreements with school food authorities.

Recipient of the School Lunch Program in 1936.

Generally, public or nonprofit private schools of high school grade or under and public or nonprofit private residential child care institutions may or may not participate in the school lunch program. School districts and independent schools that choose to take part in the lunch program get cash minimal subsidies and donated commodities from the USDA for each meal they serve. In return, they must serve lunches that meet Federal requirements, and they must offer free or reduced price lunches to eligible children. School food authorities can also be reimbursed for snacks served to children through age 18 in after-school educational or enrichment programs.

School lunches must meet the applicable recommendations of the Dietary Guidelines for Americans, which state that no more than 30 percent of an individual's calories come from fat, and less than 10 percent from saturated fat. Regulations also establish a standard for school lunches to provide one-third of the Recommended Dietary Allowances of protein, Vitamin A, Vitamin C, iron, calcium, and calories. School lunches must meet Federal nutrition requirements over the course of one week's worth of lunches served, but decisions about what specific foods to serve and how they are prepared are made by local school food authorities. The 2007 School Nutrition and Dietary Assessment III (SNDA III) study based on research by the U.S. Department of Agriculture during the 2004-2005 school year found that students in more than 90% of schools surveyed had the opportunity to select lunches that were consistent with dietary standards for fat and saturated fat.

School nutrition programs are increasingly using more whole grains, fruits and vegetables, lean protein and lowfat dairy in school lunches. Efforts such as the Local School Wellness Policies required by the 2004 Child Nutrition and WIC Reauthorization Act have involved parents, students and the school community in efforts to promote healthy eating environments and increased physical activity throughout school campuses.

In 2009, the Institute of Medicine of the National Academies released School Meals: Building Blocks For Healthy Children which reviewed and provided recommendations to update the nutrition standard and the meal requirements for the National School Lunch Program and School Breakfast Program. School Meals also set standards for menu planning that focus on food groups, calories, saturated fat, and sodium and that incorporate Dietary Guidelines for Americans and the Dietary Reference Intakes.

Unhealthy school lunches are one of the contributors of malnutrition in the form of excessive consumption of unhealthy foods, however, some measures are being taken to change that. An example is the Berkeley Food System project which utilizes vegetable gardens to promote education for healthy eating. Janet Brown,who started the project explained that students are more likely to eat healthy foods such as fruits and vegetables if they are better introduced to them.

Free school meals

HealthTeacher

National School Meals Week (in the UK)

Nutrition

Personal, Social and Health Education

School Food Trust

School Health Education Study

School health services

Share Our Strength

Welfare

(source:wikipedia)

Denial of pregnanc

Denial of pregnancy,

(also called pregnancy denial) is a rare form of denial exhibited by women to either the fact or the implications of their own pregnancy. One study found that women who denied their pregnancy represented only 0.26% of all deliveries. 

Signs and symptoms

Denial of pregnancy can be divided into three distinct types which are distinguished primarily by the severity of the denial experienced by the woman:

Affective Denial

This type of denial is characterized by a lack of the typical maternal bonding that is felt by most women during pregnancy. Although they are aware of their pregnancy, women with this disorder continue to behave as if they were not pregnant. They do not alter their clothes or lifestyle, nor do they make any preparations for the baby's arrival.

Pervasive Denial

In this form of pregnancy denial, the women suppresses all awareness of her pregnancy for extended periods of time, up to, including and even after childbirth. This psychological suppression is combined with a lack or lessening of physical symptoms of pregnancy. Women may, for example, experience little to no weight gain, or they may continue bleeding vaginally (similar to that experienced during menstruation) throughout the duration of their pregnancy.

Psychotic Denial

This is a form of denial that is so extreme as to fall under the category of delusion. While physical symptoms of pregnancy do usually occur they are misinterpreted in ways that are usually considered quite bizarre. The sensation of something growing inside the woman can be interpreted as cancer, or a blood clot, and fetal movements as the woman's organs coming loose inside her body.

(source:wikipedia)

Hypercoagulability in pregnancy

Hypercoagulability in pregnancy is the propensity of pregnant women to develop thrombosis (blood clots). Pregnancy itself is a factor of hypercoagulability (pregnancy-induced hypercoagulability) as a physiologically adaptive mechanism to prevent postpartum hemorrhage. However, when combined with an additional underlying hypercoagulable states, the risk of thrombosis or embolism may become substantial.

Causes

Pregnancy-induced hypercoagulability is probably a physiologically adaptive mechanism to prevent postpartum hemorrhage. Pregnancy changes the plasma levels of many clotting factors like fibrinogen, which can rise up to three times the normal value. Thrombin levels increase.Protein S, an anticoagulant, decreases. However, the other major anticoagulants, protein C and antithrombin III, remain constant.Fibrinolysis is impaired by an increase in plasminogen activator inhibitor-1 (PAI-1 or just PAI) and plasminogen activator inhibitor-2 (PAI-2), the latter synthesized from the placenta. Venous stasis may occur at the end of the first trimester, due to enhanced compliance of the vessel walls by a hormonal effect. 

There are also many pregnancy-related causes of hypercoagulability, e.g. the prolonged bed rest that often occurs postpartum that occurs in case of delivery by forceps, vacuum extractor or Caesarean section. Pregnancy after the age of 35 augments the risk of VTE, as does multigravidity of more than 4 pregnancies. Several pregnancy complications, like preeclampsia, cause substantial hypercoagulability.

General causes of hypercoagulability, that are approximately as common in pregnancy as in the general population, include both acquired ones such as antiphospholipid antibodies, and congenital ones, including Factor V Leiden mutation, prothrombin mutation, protein C and S deficiencies and antithrombin III deficiency.

Complications

Deep vein thrombosis has an incidence of 1 in 1,000 to 2,000 pregnancies in the United States, and is the second most common cause of maternal death in developed countries after bleeding.

Prevention of thrombosis with anticoagulants

While the consensus among physicians is that the safety of the mother supersedes the safety of the developing fetus, changes in the anticoagulation regimen during pregnancy can be performed to minimize the risks to the developing fetus while maintaining therapeutic levels of anticoagulation in the mother.

The main issue with anticoagulation in pregnancy is that warfarin, the most commonly used anticoagulant in chronic administration, is known to have teratogenic effects on the fetus if administered in early pregnancy.Still, there seems to be no teratogenic effect of warfarin before 6 weeks of gestation. On the other hand, unfractionated heparin and low molecular weight heparin (LMWH) do not cross the placenta.

Indications

In general, the indications for anticoagulation during pregnancy are the same as the general population. This includes (but is not limited to) a recent history of deep venous thrombosis (DVT) or pulmonary embolism, a metallic prosthetic heart valve, and atrial fibrillation in the setting of structural heart disease.

In addition to these indications, anticoagulation may be of benefit in individuals with SLE and a history of previous spontaneous abortions,[citation needed] individuals who have a history of deep venous thrombosis (DVT) or pulmonary embolism (PE) associated with a previous pregnancy,[citation needed] and even with individuals with a history of coagulation factor deficiencies and DVT not associated with a previous pregnancy.

Strategies

There is no consensus on the correct anticoagulation regimen during pregnancy. Treatment is tailored to the particular individual based on their risk of complications. Warfarin and other vitamin K inhibiting agents are contraindicated during the first trimester of pregnancy because of the teratogenic effects, and should not be administered when pregnancy confirmed.Rather, women who are on chronic anticoagulation may be given the option of conversion to either unfractionated heparin or low molecular weight heparin (LMWH) such as tinzaparin prior to a planned conception. LMWH is as safe and efficacious as unfractionated heparin. A blood test including platelets and a clotting screen should be performed prior to administration of anticoagulant regimens in pregnancy.

Subcutaneous tinzaparin may be given at doses of 175 units of anti-factor Xa activity per kg,based on pre-pregnancy or booking weight at approximately 16 weeks, and not the current weight. While unfractionated heparin is otherwise typically given in an intravenous formulation, this is inconvenient for the prolonged period of administration required in pregnancy.

Whether warfarin can be re-initiated after the twelfth week of pregnancy is unclear. In a recent retrospective analysis, it was suggested that resumption of warfarin after the first trimester is completed is associated with increased risk of loss of the fetus. However, this analysis included only individuals who were anticoagulated for mechanical heart valves, which generally require high levels of anticoagulation.

In pregnant women with mechanical heart valves, the optimal anticoagulation regimen is particularly unclear. It is clear from prior studies that anticoagulation with subcutaneous heparin in this setting is associated with a high incidence of thrombosis of the valve and death. Similar issues are likely associated with the use of enoxaparin (a low molecular weight heparin) in these high-risk individuals.

By risk score

Prevention of deep vein thrombosis and other types of venous thrombosis may be required if there are certain predisposing risk factors. One example is based on the point system below, where points are summed together to give the appropriate prophylaxis regimen.

Points Risk factors

1 point

Minor factors

Heterozygous for factor V Leiden mutation

Heterozygous for factor II mutation

Overweight, in this case defined as a BMI > 28 at early pregnancy

Caesarean section

DVT heredity in a first-degree relative

Age > 40 years

Pre-eclampsia

Hyperhomocysteinemia

2 points

Intermediate risk factors

Protein S or C deficiency

Immobilization (after e.g. bone fracture or prolonged bed rest

3 points

Intermediate risk factors

Homozygous for factor V Leiden mutation

Homozygous for factor II mutation

4 points

Severe risk factors

Previous DVT

Antiphospholipid syndrome without previous DVT

Lupus anticoagulant

Very high risk

Artificial heart valves

Antithrombin III deficiency

Multiple previous thromboses

Antiphospholipid syndrome with previous DVT

Previous pulmonary embolism

After adding any risk factors together, a total of 1 point or less indicates that no preventive action is needed.A total of 2 points indicates that short-term prophylaxis, e.g. with low molecular weight heparin, may be used in temporary risk factors, as well as administering prophylactic treatment 7 days postpartum, starting a couple of hours after birth. A total of 3 points increases the necessary duration of postpartum prophylaxis to 6 weeks.

A risk score of 4 points or higher means that there should probably be prophylaxis in the antepartum period, as well as at least 6 weeks postpartum.A previous distal DVT motivates a minimum of 12 weeks (3 months) of therapeutic anticoagulation therapy.A previous proximal DVT or pulmonary embolism motivates a minimum of 26 weeks (6.5 months) of therapy If the therapy duration reaches delivery time, the remaining duration may be given postpartum, possibly extending the minimum of 6 weeks postpartum therapy. In a very high risk, there should be a high-dose antepartum prophylaxis, continued at least 12 weeks postpartum.

Women with antiphospholipid syndrome should have an additional low dose prophylactic treatment of Aspirin.

Cautions

All anticoagulants (including LMWH) should be used with caution in women with suspected coagulopathy, thrombocytopaenia, liver disease and nephropathy.

Major side effects of tinzaparin are osteoporosis (occurring in up to 1% of cases), thrombocytopenia (heparin-induced thrombocytopenia), haemorrhage, hair loss and drug allergy. Still, LMWHs are much less likely to cause heparin-induced thrombocytopenia than unfractionated heparin.

Regional anaesthesia is contraindicated in women on therapeutic anticoagulation, and should not be used within 24 hours of the last dose of tinzaparin. 

Monitoring

Anticoagulant therapy with LMWH is not usually monitored.LMWH therapy does not affect the prothrombin time (PT) or the INR, and Anti Xa levels are not reliable. It can prolong the Partial thromboplastin time (APTT) in some women, but still, the APTT is not useful for monitoring.

In order to check for any thrombocytopenia, platelet count should be checked prior to commencing anticoagulant therapy, then 7 to 10 days after commencement, and monthly thereafter.Platelet count should also be checked if unexpected bruising or bleeding occurs.

Reversal

Protamine reverses the effect of unfractionated heparin but only partially binds to and reverses LMWH. A dose of 1mg protamine/100IU LMWH reverses 90% of its anti-IIa and 60% of anti-Xa activity, but the clinical effect of the residual anti Xa activity is not known.Both anti-IIa and anti Xa activity may return up to three hours after protamine reversal, possibly due to release of additional LMWH from depot tissues.

Anticoagulants in breastfeeding

Warfarin, heparin and LMWH do not seem to pass into breast milk, so these are not contraindicated in breastfeeding.

(source:wikipedia)

Amniotic stem cells

Amniotic stem cells are multipotent stem cells of mesenchymal origin extracted from amniotic fluid

Amniotic stem cells are able to differentiate into various tissue type such as skin, cartilage, cardiac tissue, nerves, muscle, and bone, and may have potential future medical applications.

All over the world, universities and research institutes are studying amniotic fluid to discover all the qualities of amniotic stem cells, and scientist such as Anthony Atala, Paolo De Coppi and Giuseppe Simoni  have discovered important results.

Ethical aspect

From an ethical point of view, stem cells from amniotic fluid provides a noncontroversial alternative to embryonic stem cells because they are harvested without destroying embryos. For example, the Vatican newspaper "Osservatore Romano", the newspaper of the Holy See has even called amniotic stem cells "the future of medicine" .

Amniotic stem cells banks

Thanks to recent studies , supported in part by Lombardy italian region (Italy) leader Roberto Formigoni, it is possible to bank stem cells derived from amniotic fluid in private stem cells banks .

In 2009, the first US amniotic stem cell bank was opened in Medford, MA, by Biocell Center, an international company specializing in the cryopreservation and private banking of amniotic fluid stem cells.

(source:wikipedia)

Amniocentesis

Amniocentesis (also referred to as amniotic fluid test or AFT), is a medical procedure used in prenatal diagnosis of chromosomal abnormalities and fetal infections [1], in which a small amount of amniotic fluid, which contains fetal tissues, is extracted from the amnion or amniotic sac surrounding a developing fetus, and the fetal DNA is examined for genetic abnormalities.

Procedure

Before the start of the procedure, a local anesthetic can be given to the mother in order to relieve the pain felt during the insertion of the needle used to withdraw the fluid. After the local is in effect, a needle is usually inserted through the mother's abdominal wall, then through the wall of the uterus, and finally into the amniotic sac. With the aid of ultrasound-guidance, a physician punctures the sac in an area away from the fetus and extracts approximately 20 ml of amniotic fluid. After the amniotic fluid is extracted, the fetal cells are separated from the sample. The cells are grown in a culture medium, then fixed and stained. Under a microscope the chromosomes are examined for abnormalities. The most common abnormalities detected are Down syndrome, Edward syndrome (trisomy 18) and Turner syndrome (monosomy X). In regards to the fetus, the puncture heals and the amniotic sac replenishes the liquid over the next 24–48 hours.

Indications & results

Early in pregnancy, used for diagnosis of chromosomal and other fetal problems such as:

Down Syndrome (Trisomy 21)

Trisomy 13

Trisomy 18

Fragile X

Rare, inherited metabolic disorders

Neural tube defects (anencephaly and spina bifida) by alpha-fetoprotein levels.

Later on, it also can be used to detect problems such as:

Infection

Rh incompatibility

prediction of lung maturity

decompression of polyhydramnios

An emerging indication for amniocentesis is in the management of preterm rupture of membranes where measurement of certain amniotic fluid inflammatory markers may be helpful. If amniotic fluid IL-6, a marker of inflammation, is elevated, the fetus is at high risk and delivery should be considered. 

Risks and drawbacks

Amniocentesis is performed between the 15th-20th week of pregnancy; performing this test early can lead to injury to the baby's limbs. Most people do the test during the 18th week of pregnancy. The term "early amniocentesis" is sometimes used to describe use of the process between weeks 11 and 13. Approximately 6 percent of pregnant women take or consider taking the amniocentesis test.

Although the procedure is routine, and almost 70% of women who undergo the test report little to no discomfort[6], possible complications include infection of the amniotic sac from the needle, and failure of the puncture to heal properly, which can result in leakage or infection. Serious complications can result in miscarriage. Other possible complications include preterm labor and delivery, respiratory distress, postural deformities, fetal trauma and alloimmunisation of the mother (rhesus disease). Studies from the 1970s originally estimated the risk of amniocentesis-related miscarriage at around 1 in 200 (0.5%).A more recent study (2006) has indicated this may actually be much lower, perhaps as low as 1 in 1,600 (0.06%). In contrast, the risk of miscarriage from chorionic villus sampling (CVS) is believed to be approximately 1 in 100, although CVS may be done up to four weeks earlier, and may be preferable if the possibility of genetic defects is thought to be higher.

One simple drawback is that administration may be painful.

Amniotic fluid embolism has been described as a possible risk.

Amniocentesis and stem cells

Recent studies have discovered that amniotic fluid can be a rich source of multipotent mesenchymal, hematopoietic, neural, epithelial and endothelial stem cells.

A potential benefit of using amniotic stem cells over those obtained from embryos is that they side-step ethical concerns among pro-life activists by obtaining pluripotent lines of undifferentiated cells without harm to a fetus or destruction of an embryo.

Artificial heart valves, working tracheas, as well as muscle, fat, bone, heart, neural and liver cells have all been engineered through use of amniotic stem cells. Tissues obtained from amniotic cell lines show promise for patients suffering from congenital diseases/malformations of the heart, liver, lungs, kidneys, and cerebral tissue.

The first amniotic stem cells bank in US is active in Boston, Massachusetts.

(source:wikipedia)

Drugs in pregnancy

Drugs used during pregnancy,

can have temporary or permanent effects on the fetus. Any drug that acts during embryonic or fetal development to produce a permanent alteration of form or function is known as a teratogen.

for the pregnant woman

Many physicians would prefer not to prescribe for pregnant women, the major concern being over teratogenicity of the drugs. The apprehension is not necessarily data driven and is mostly due to lack of clinical studies in pregnant women. This can result in inappropriate treatment of pregnant women and fetus. Use of drugs in pregnancy is not always wrong. For example, high fever is harmful for the fetus in the early months, thus the use of paracetamol (acetaminophen) is generally associated with lower risk than the fever itself. Similarly, diabetes mellitus during pregnancy may need intensive therapy with insulin to prevent complications to mother and baby.

Period of drug use

Pregnancy and development of fetus progresses through various changes. The period of one week from fertilisation to implantation of the fertilized egg is called preimplantation period. This is an 'all or none' period, .i.e an insult can either cause death or complete recovery. The period from the 8th day to the end of 8th week (2nd month) is the period of organogenesis during which the organs are formed in the fetus. This is the most crucial time with regard to 'structural malformations' and concern over teratogenicity of drugs. From the 3rd month week to the end of 9 months is the period of fetal maturation. Intake of drugs during this period may modify the 'function' of the fetal organs rather than causing gross structural malformations in the fetus, for example, aminoglycosides can affect the functioning of kidneys and also the hearing mechanism.

Categories of drugs

The Food and Drug Administration (FDA) has developed a rating system to provide therapeutic guidance based on potential benefits and fetal risks. Drugs have been classified into categories A, B, C, D and X based on this system of classification. Drugs like multivitamins that have demonstrated no fetal risks after controlled studies in humans are classified as Category A. On the other hand drugs like thalidomide with proven fetal risks that outweigh all benefits are classified as Category X.

Classification of a few important drugs/vaccines

Antibacterial agents

Category B : Penicillin, metronidazole, nitrofurantoin, cephalosporins, clindamycin, terbinafine, some macrolides e.g. azithromycin, erythromycin

Category C : Some aminoglycosides, chloroquine, quinolones, mebendazole, fluconazole

Category D : Tetracyclines, gentamicin, tobramycin

Cardiovascular drugs

Category B : Heparin (LMW)

Category C : Heparin (conventional), beta-blockers, (dihydropyridine) calcium antagonists, furosemide, digoxin, methyldopa

Category D : ACE inhibitors, ARBs, coumarins, thiazides, diltiazem

Central nervous system drugs

Category B : Acetaminophen, caffeine

Category C : Aspirin, clonidine, rofecoxib

Category D : Carbamezapine, valproic acid, diazepam, lithium

Vaccines

Category C : Tetanus toxoid, polio vaccine , BCG vaccine, hepatitis A vaccine, hepatitis B vaccine and rabies vaccine.

(source:wikipedia)

Immune tolerance in pregnancy

Immune tolerance in pregnancy, or gestational immune tolerance,

is the absence of a maternal immune response against the fetus and placenta, which thus may be viewed as unusually successful allografts, since they genetically differ from the mother.In the same way, many cases of spontaneous abortion may be described in the same way as maternal transplant rejection.

Mechanisms

Placental mechanisms

The placenta functions as an immunological barrier between the mother and the fetus.

The placenta functions as an immunological barrier between the mother and the fetus, creating an immunologically privileged site. For this purpose, it uses several mechanisms:

It secretes Neurokinin B containing phosphocholine molecules. This is the same mechanism used by parasitic nematodes to avoid detection by the immune system of their host.

Also, there is presence of small lymphocytic suppressor cells in the fetus that inhibit maternal cytotoxic T cells by inhibiting the response to interleukin 2.

The placental trophoblast cells do not express the classical MHC class I isotypes HLA-A and HLA-B, unlike most other cells in the body, and this absence is assumed to prevent destruction by maternal cytotoxic T cells, which otherwise would recognize the fetal HLA-A and HLA-B molecules as foreign. On the other hand, they do express the atypical MHC class I isotypes HLA-E and HLA-G, which is assumed to prevent destruction by maternal NK cells, which otherwise destruct cells that do not express any MHC class I.However, trophoblast cells do express the rather typical HLA-C.

It forms a syncytium without any extracellular spaces between cells in order to limit the exchange of migratory immune cells between the developing embryo and the body of the mother (something an epithelium will not do sufficiently, as certain blood cells are specialized to be able to insert themselves between adjacent epithelial cells). The fusion of the cells is apparently caused by viral fusion proteins from endosymbiotic endogenous retrovirus (ERV). [4] An immunoevasive action was the initial normal behavior of the viral protein, in order to avail for the virus to spread to other cells by simply merging them with the infected one. It is believed that the ancestors of modern viviparous mammals evolved after an infection by this virus, enabling the fetus to better resist the immune system of the mother.

Still, the placenta does allow maternal IgG antibodies to pass from to the fetus to protect it against infections. However, these antibodies do not target fetal cells, unless any fetal material has escaped across the placenta where it can come in contact with maternal B cells and make those B cells start to produce antibodies against fetal targets. The mother does produce antibodies against foreign ABO blood types, where the fetal blood cells are possible targets, but these preformed antibodies are of the IgM type,and do not cross the placenta.

Other mechanisms

Still, the placental barrier is not the sole means to evade the immune system, as foreign fetal cells also persist in the maternal circulation, on the other side of the placental barrier.

In any case, the placenta does not block maternal IgG antibodies, which thereby may pass through the human placenta, providing immune protection to the fetus against infectious diseases.

One model for the induction of tolerance during the very early stages of pregnancy is the Eutherian Fetoembryonic Defense System (eu-FEDS) hypothesis. The basic premise of the eu-FEDS hypothesis is that both soluble and cell surface associated glycoproteins, present in the reproductive system and expressed on gametes, suppress any potential immune responses, and inhibit rejection of the fetus . The eu-FEDS model further suggests that specific carbohydrate sequences (oligosaccharides) are covalently linked to these immunosuppressive glycoproteins and act as “functional groups” that suppress the immune response. The major uterine and fetal glycoproteins that are associated with the eu-FEDS model in the human include alpha-fetoprotein, CA125, and glycodelin-A (also known as placental protein 14 (PP14)).

Regulatory T cells also likely play a role.[9].

Also, a shift from cell-mediated immunity toward humoral immunity is believed to occur.

Insufficient tolerance

Many cases of spontaneous abortion may be described in the same way as maternal transplant rejection. Other examples of insufficient immune tolerance in pregnancy are Rh disease and pre-eclampsia:

Rh disease is caused by the mother producing antibodies (including IgG antibodies) against the Rhesus D antigen on her baby's red blood cells. It occurs if the mother is Rh negative and the baby is Rh positive, and a small amount of Rh positive blood from any previous pregnancy has entered the mother's circulation to make her produce IgG antibodies against the Rhesus D antigen. Maternal IgG is able to pass through the placenta into the fetus and if the level of it is sufficient, it will cause destruction of Rhesus D positive fetal red blood cells leading to development Rh disease. Generally Rhesus disease becomes worse with each additional Rhesus incompatible pregnancy.

One cause of pre-eclampsia is an abnormal immune response towards the placenta. There is substantial evidence for exposure to partner's semen as prevention for pre-eclampsia, largely due to the absorption of several immune modulating factors present in seminal fluid.

Increased infectious susceptibility

The immunologic changes in pregnancy alters the susceptibility to and severity of infectious diseases. For example, pregnancy may increase susceptibility to toxoplasmosis and listeriosis and may increase severity of illness and increase mortality rates from influenza and varicella. 

Xenopregnancy

If the mechanisms of rejection-immunity of the fetus could be elucidated, it could avail for xenopregnancy, having, for example pigs carry human fetuses to term as an alternative to a human surrogate mother, providing a sober, drug-free and nonsmoking carrier.

(source:wikipidia)

Nutrition and pregnancy

Nutrition and pregnancy,

refers to the nutrient intake, and dietary planning that is undertaken before, during and after pregnancy. All dietary advice relating to pregnancy-related nutrition is noted by Mary E. Barasi as one of the major factors in determining the future well-being of a child conceived, some factors of a diet are even noted to reduce childhood morbidity and mortality due to helping the supply of nutrients to the mother. 

In a precursory study into the link between nutrition and pregnancy in 1950 women who consumed minimal amounts over the eight week period had a higher mortality or disorder rate concerning their offspring than women who ate regularly, because children born to well-fed mothers had less restriction within the womb. 

Not only have physical disorders been linked with poor nutrition before and during pregnancy, but neurological disorders and handicaps are a risk that is run by mothers who are malnourished, a condition which can also lead to the child becoming more susceptible to later degenerative disease(s). 

The following sections refer to the pertinence of nutrition throughout pregnancy, and are thoroughly researched enough to be usable for mothers or couples planning on conceiving.

Nutrition before pregnancy

Potentially harmful pre-pregnancy determinants

It is known that good nutrition before pregnancy is important because of the amount of "resources" childbirth requires. The process of pre-pregnancy nutrition is a process of "building up" the immune system in preparation of pregnancy, and is known as being one of the major factors in determining the success rate of conceiving healthy children.

As with most situations, the most important factor in pre-pregnancy nutrition is ensuring that the mother is healthy and without any major factors which could worsen the chances of conceiving, factors such as anorexia or bulimia are thought to be direct links with infertility; the minimum body mass index for conceiving mothers being 20.8.

This is also seen to be true with obese women with a BMI above 30 which is a direct result of decrementing amounts of insulin activity and sex hormones may reduce the viability of the ovum.

The ideal range of weight for women wishing to conceive children is thought to be optimal at body mass indexes between 20 and 26. If this, again, is used in conjunction with good nutrition and diet before pregnancy in terms of a normal balanced diet, then reserves of micronutrients, providing materials for pregnancy, would also be maximised.

For more information on how BMI is calculated, please refer to the body mass index article.

Beneficial pre-pregnancy nutrients

As with most diets, there are chances of over-supplementing, however, as general advice, both state and medical recommendations are that mothers follow instructions listed on particular vitamin packaging as to the correct or recommended daily allowance (RDA).

Magnesium and zinc supplementation for the binding of hormones at their receptor sites.

Folic acid supplementation, or dietary requirement of foods containing it for the regular growth of the follicle.

Regular Vitamin D supplementation decreases the chances of deficiencies in adolescence. More importantly, it is known to reduce the likelihood of rickets with pelvic malformations which make normal delivery impossible.

Regular Vitamin B12 supplementation, again is known to reduce the chances of infertility and ill health.

Nutrition during pregnancy

The conception and the subsequent weeks afterwards is the time when it is at its most vulnerable, as it is the time when the organs and systems develop within. The energy used to create these systems comes from the energy and nutrients in the mother's circulation, and around the lining of the womb, such is the reason why correct nutrient intake during pregnancy is so important.

During the early stages of pregnancy, the placenta is not formed yet, so there is no mechanism to protect the embryo from the deficiencies which may be inherent in the mother's circulation, so it is critical that the correct amount of nutrients and energy are consumed.

Potentially harmful determinants during pregnancy

Intake of retinol, in extreme cases, has been linked to birth defects and abnormalities. However, regular intake of retinol is not seen as dangerous. It is noted that a 100 g serving of liver may contain a large amount of retinol, so it is best that it is not eaten daily during pregnancy, something which is also the same with alcohol intake in binge drinking.

Excessive amounts of alcohol have been proven to cause Fetal alcohol syndrome. The World Health Organization recommends that alcohol should be avoided entirely during pregnancy, given the relatively unknown effects of even small amounts of alcohol during pregnancy.

Maternal obesity has a significant impact on maternal metabolism and offspring development. Insulin resistance, glucose homeostasis, fat oxidation and amino acid synthesis are all disrupted by maternal obesity and contribute to adverse outcomes. Modification of lifestyle is an effective intervention strategy for improvement of maternal metabolism and the prevention of adverse outcomes.

Recommended nutrients during pregnancy

Nutrient	Recommendation (Extra = Above RDA)	Maximum/Total amount
Energy	Increase by 200 kcal (840 kJ) per day in last trimester only.	RDA
Proteins	Extra 6 g per day	51 g per day
Thiamin	Increase in line with energy; increase by 0.1 mg per day	0.9 mg per day
Riboflavin	Needed for tissue growth; extra 0.3 mg per day	1.4 mg per day
Niacin	Regular supplementation/diet of substance. No increase required.	RDA
Folate	Maintain plasma levels; extra 100 µg per day	300 µg per day
Vitamin C	Replenish drained maternal stores; extra 120 mg per day	50 mg per day
Vitamin D	Replenish plasma levels of vitamin 10 µg per day.	RDA
Calcium	Needs no increase	RDA
Iron	Extra 3 mg per day needed	RDA
Magnesium, zinc, and copper	Normal supplementation or consumption.	RDA
Iodine	Extra 100 µg per day.	250 µg per day

Folate

Deficiencies in folic acid may cause neural tube defects; women who had 4 mg of folic acid in their systems due to supplementing 3 months before childbirth significantly reduced the risk of NTD within the fetus. This is now advocated by the UK department of health, recommending 400 µg per day of folic acid.

Folate and Acute Lymphoblastic Leukemia

Along with neural tube development, folate affects DNA synthesis in multiple ways. As Ball explains, folate is involved in the construction of purines and pyrimidines, the building blocks of nucleic acids. Folate is also necessary to make s-adenosylmethionine (SAM), which acts as a methyl donor in the synthesis of DNA. Because of its role in these important mechanisms, fetal DNA would be significantly altered if a maternal folate deficiency is present. One possible outcome is DNA mutation, which could prevent normal gene expression. For example, a tumor-suppressing gene might be turned off, altering normal immune function in preventing cancer growth. Thompson et al.  examined the relationship between maternal supplementation of folate and iron during pregnancy and incidences of acute lymphoblastic leukemia (ALL) in their children. Increased rates of ALL were found in children whose mothers did not take iron and folate supplements. Iron alone did not seem to reduce the risk of developing ALL, however iron in combination with folate was shown to have a protective effect in decreasing the risk for ALL. Thompson and his associates (2001), concluded that maternal folate supplementation throughout pregnancy plays an important role in reducing the risk for childhood ALL 

Nutrition after pregnancy

Proper nutrition is important after delivery to help the mother recover, and to provide enough food energy and nutrients for a woman to breastfeed her child. Women having serum ferritin <= 70 µg/L may need iron supplements to prevent iron deficiency anaemia during pregnancy and postpartum.

(source:wikipedia)

Prenatal car

Prenatal car,

 refers to the medical and nursing care recommended for women before and during pregnancy. The aim of good prenatal care is to detect any potential problems early, to prevent them if possible (through recommendations on adequate nutrition, exercise, vitamin intake etc), and to direct the woman to appropriate specialists, hospitals, etc. if necessary. The availability of routine prenatal care has played a part in reducing maternal death rates and miscarriages as well as birth defects, low birth weight, and other preventable infant problems in the Fiscella 1995. Animal studies indicate that mothers' (and possibly fathers') diet, vitamin intake, and glucose levels prior to ovulation and conception have long-term effects on fetal growth and adolescent and adult disease.

While availability of prenatal care has considerable personal health and social benefits, socioeconomic problems prevent its universal adoption in many developed as well as developing nations.

One prenatal practice is for the expecting mother to consume vitamins with at least 400 mcg of folic acid to help prevent neural tube defects.

Prenatal care generally consists of:

monthly visits during the first two trimesters (from week 1–28)

biweekly from 28 to week 36 of pregnancy

weekly after week 36 (delivery at week 38–40)

Assessment of parental needs and family dynamic

Physical examination

Physical examinations generally consist of:

Collection of (mother's) medical history

Checking (mother's) blood pressure

(Mother's) height and weight

Pelvic exam

Doppler fetal heart rate monitoring

(Mother's) blood and urine tests

Discussion with caregiver

Ultrasound

Obstetric ultrasounds are most commonly performed during the second trimester at approximately week 20. Ultrasounds are considered relatively safe and have been used for over 35 years for monitoring pregnancy.

Among other things, ultrasounds are used to:

Diagnose pregnancy (uncommon)

Check for multiple fetuses

Determine the sex of the fetus

Assess possible risks to the mother (e.g., miscarriage, blighted ovum, ectopic pregnancy, or a molar pregnancy condition)

Check for fetal malformation (e.g., club foot, spina bifida, cleft palate, clenched fists)

Determine if an intrauterine growth retardation condition exists

Note the development of fetal body parts (e.g., heart, brain, liver, stomach, skull, other bones)

Check the amniotic fluid and umbilical cord for possible problems

Determine due date (based on measurements and relative developmental progress)

Generally an ultrasound is ordered whenever an abnormality is suspected or along a schedule similar to the following:

7 weeks — confirm pregnancy, ensure that it's neither molar or ectopic, determine due date

13–14 weeks (some areas) — evaluate the possibility of Down Syndrome

18–20 weeks — see the expanded list above

34 weeks (some areas) — evaluate size, verify placental position

Prenatal Care and Race

Many health professionals consider prenatal care a nearly essential practice for pregnant women; however, there are wide gaps in the American population regarding who has access to these services and who actually utilizes these services. For example, African-American expectant mothers are 2.8 times as likely as non-Hispanic white mothers to begin their prenatal care in the third trimester, or to receive no prenatal care during the entirety of the pregnancy.[2] Similarly, Hispanic expectant mothers are 2.5 times as likely as non-Hispanic white mothers to begin their prenatal care in the third trimester, or to receive no prenatal care at all. The following factors impact a woman’s likelihood of acquiring prenatal care:

Health Insurance: 13% of women who become pregnant every year in the United States are uninsured, resulting in severely limited access to prenatal care. According to Children’s Defense Fund’s website, “Almost one in every four pregnant Black women and more than one in three pregnant Latina women is uninsured, compared with one in nearly seven pregnant White women. Without coverage, Black and Latina mothers are less likely to access or afford prenatal care.” Currently, pregnancy is considered a “pre-existing condition,” making it much harder for uninsured pregnant women to actually be able to afford private health insurance.

Formal Education: Oftentimes, Black and Hispanic pregnant women have fewer years of formal education, which sparks a large domino effect of consequences related to prenatal care. A lack of formal education results in less knowledge about pregnancy appropriate prenatal healthcare as a whole, fewer job opportunities, and a lower level of income throughout their adult life.
Trust & Comfort with Healthcare Industry: Many minority women have limited experience with the healthcare industry on a whole, as compared to their Caucasian counterparts. Consequently, there is a lower level of trust with physicians, nurses, and the entire care regimen. Many women who are distrustful of biomedicine will decline certain prenatal tests, citing their own bodily knowledge as more trustworthy than their doctor’s high-tech interpretations. Even worse, some minority women may opt to avoid the distress and discomfort of the medical industry and refuse prenatal care entirely.

Understanding of Prenatal Testing: Many ethnic/racial minority mothers are referred to genetic counseling and prenatal testing centers after being declared “at-risk” for birth defects after initial screenings. However, few testing centers effectively communicate what occurs during the various tests, what the test is looking for, or what the various results could mean for the remainder of the pregnancy. Therefore, some mothers are quite uncomfortable with this lack of clearly-communicated information and are consequently hesitant to pursue prenatal testing and counseling that health professionals would consider recommendable.

Consequences of Minorities’ Limited Access to Prenatal Care

Without timely, thorough, and appropriate prenatal care, the racial minorities of the United States continue to face severe consequences for the birth outcome of both infant and mother.

Delivery Complications: In one study, researchers found that all minority races experienced higher rates of complications such as: intrauterine growth restriction, preeclampsia, preterm premature rupture of membranes, gestational diabetes, placenta previa, and preterm birth.

Low Birth Weight: Black infants are almost twice as likely to be born at a low birth weight as White babies. This birth complication is ranked as the most prevalent cause of death among African American infants, claiming 1780 lives in 2005.

Congenital Malformations: Any genetic factor or prenatal event that adversely affects the development of the fetus in utero can result in a congenital malformation. Some commonly known congenital malformations are cleft palate, heart defects, and Down syndrome. As of 2005, congenital malformations are the leading cause of death among Hispanic infants, claiming 1373 lives.

Infant Mortality: In the United States, the non-Hispanic white population experiences an infant mortality rate of 5.8 deaths per every 1000 live births. The African-American population’s infant mortality rate is 2.3 times greater (13.6 deaths per 1000 live births).

Impact of Prenatal Care on Birth Outcomes: When women utilize prenatal care appropriately, many of them increase their chances of having a successful birth outcome. For example, prenatal care includes discussions with physicians about what lifestyle changes should be made during pregnancy (such as tobacco or alcohol cessation); if these changes do not occur, the pregnancy is more likely to be problematic or result in an infant with a defect or prone to early mortality. Additionally, doctors can provide prescriptions for specific prenatal vitamins and supplements to ensure a healthy mother and infant. Finally, specific prenatal tests screen for genetic abnormalities, and expectant mothers can learn if their fetuses have any significant defects prior to delivery; in these situations, physicians and genetic counselors can help advise mothers about their options for continuing the pregnancy. While some poor birth outcomes cannot be entirely avoided through prenatal care, the pregnant woman can receive important information, advice, and guidance about her own individual situation, rather than being surprised in the delivery room with some unexpected news.

Pregnancy and Exercise: Updated recommendations by the American College of Sports Medicine suggest at least 2-1/2 hours of moderate-intensity aerobic activity spread throughout the week for pregnant and postpartum women. Women who regularly engage in high-intensity or higher amounts of activity may continue under the counsel of their health care professional provided their condition remains unchanged. For more information on the exercise recommendations and the survey of health professionals, go to http://www.acsm.org. 

Prenatal Care Improvements for Minorities

http://maapatashala.com/index.htm Although minorities continue to face decreased access to high-quality prenatal care, there are specific improvements the biomedical field can make to fix this disparity.

Connect physicians and patients on a cultural level: For many minority patients, it is difficult to develop a long-standing and trusting relationship with healthcare providers of different cultural backgrounds, as each culture has its own priorities, values, and goals.[20] In traditionally underserved communities with sizeable minority populations, healthcare providers should strive to offer physicians and nurses who match the racial background of the patients they are working to serve.

Improve all providers’ cultural awareness and sensitivity: If patients cannot be matched with healthcare providers culturally, then they should at least be able to visit a physician who is trained specifically to deal with cultural differences. This awareness and sensitivity can come in many forms, such as a familiarity with a foreign language, an understanding of how a specific ethnicity views mothers, or knowing how family networks play into the mothers’ decision-making process. All of these options have the potential to improve doctor-patient relationships, and this sort of education can be implemented in medical training programs both in medical school settings and on-site training programs.

Community Outreach Programs: Because hospitals and doctors’ offices are unfamiliar and unwelcoming places for some individuals, the healthcare industry should establish a multifaceted community outreach program in large cities. These programs would train members of the minority population in basic health education; then these community health workers would help to facilitate connections between expectant mothers and local healthcare establishments. The community health workers could even continue their relationship throughout the duration of the pregnancy, serving as a patient liaison during the various tests, appointments, and conversations.

(source:wikipedia)