During pregnancy, most mothers strive to learn as much as possible about nutrition and how to eat a healthy diet. Surprisingly, some healthy foods can also pose a risk to the fetus if not prepared properly. Food-borne infections can be more dangerous during pregnancy. Some foods should be avoided by pregnant women as they may have a negative impact on fetal growth and development.
Fish and Shellfish
Mercury is a type of industrial air pollution that becomes methylmercury when it lands in streams and oceans. This substance is harmful to the nervous system of unborn babies whose mothers eat fish that inhabit contaminated waters. Depending on their position in the foodchain, the levels of toxins in different species of fish vary. Pregnant women should avoid shark, swordfish, king mackerel or tilefish. The U.S. Food and Drug Administration (FDA) recommends no more than two 12-ounce servings per week of shrimp, canned light tuna, salmon, pollock and catfish. Do not eat raw fish or shellfish while pregnant.
Liver
Don't eat too much liver during pregnancy because it is a rich source of vitamin A, cautions the Mayo Clinic. Excessive intake of vitamin A has been linked with birth anomalies such as cleft palate and heart defects. Orange/yellow vegetables such as carrots, yams and pumpkin contain beta carotene, which the body converts to only the amount of vitamin A it needs, making these foods a safe choice.
Caffeine
In 2008, a study followed 2,635 low-risk pregnant women from first trimester to birth in two UK hospital maternity units in order to assess the impact of caffeine on fetal growth and development. The results, published in the "British Medical Journal," found consumption of more than 200mg of caffeine per day was associated with fetal growth restriction. The CARE Study Group conducted the research and further explained that caffeine is rapidly absorbed into the bloodstream and crosses the placenta. After a 200mg dose of caffeine, blood flow within the placenta was reduced by 25 percent.
Undercooked Foods
Listeriosis is an illness caused by the food-borne Listeria bacteria. Mothers in the third trimester of pregnancy are particularly vulnerable to flu-like symptoms: headache, body aches, fever, nausea and vomiting. Listeria can be transmitted to the baby, causing pregnancy loss, preterm birth, stillbirth and neonatal death. Undercooked meats, eggs, soft cheeses made with unpasteurized milk, pates and luncheon or deli meats are most likely to harbor the bacteria, according to the March of Dimes.
