What Not to Eat in the First Trimester: 13 Foods Pregnant Women Should Avoid

According to the Family Magazine section of Saed News, pregnancy is a sensitive and pivotal period, and a mother’s diet plays a crucial role in protecting both her health and her baby’s development. One of the most common questions expectant mothers ask is: What should I avoid eating during the first trimester?

During these first three months, when the baby is forming, consuming certain foods can harm fetal development or endanger the mother’s health. Knowing which foods to avoid can prevent serious complications and provide peace of mind.

Foods to Avoid During the First Trimester

1. Fish High in Mercury
Mercury is a highly toxic element found mainly in polluted waters and should be avoided during pregnancy. High levels can damage the nervous system, immune system, and kidneys, and even small amounts can affect a child’s development.

Large predatory fish, such as shark, swordfish, tuna (especially bigeye), marlin, and king mackerel, often contain high mercury levels and are therefore unsafe.

2. Raw or Undercooked Seafood
Raw seafood can carry bacterial and parasitic infections, including norovirus, Vibrio, Salmonella, and Listeria. Some infections only cause dehydration and weakness in the mother, while others can cross the placenta and increase the risk of premature birth, miscarriage, stillbirth, or other serious complications.

Pregnant women are particularly vulnerable to Listeria; the CDC reports they are 10 times more likely to contract it than the general population. Raw fish may become contaminated during handling, storage, or processing.

3. Undercooked or Raw Meat
While meat is a valuable source of protein and iron—essential for maternal and fetal health—undercooked or raw meat can carry bacteria or parasites such as Toxoplasma, E. coli, Listeria, and Salmonella. These pathogens can harm the fetus, potentially causing stillbirth or severe neurological issues like intellectual disability, blindness, or epilepsy.

4. Processed Meats
Hot dogs and other processed meats may harbor bacteria from processing or storage. They are also high in sodium and unhealthy fats, which should be limited during pregnancy.

5. Raw Eggs
Raw eggs can carry Salmonella. Symptoms include fever, nausea, vomiting, cramps, and diarrhea, and in rare cases, infection can trigger uterine contractions, increasing the risk of premature birth or miscarriage. Pregnant women should avoid soft-boiled eggs and foods containing raw eggs, such as homemade mayonnaise or ice cream. Pasteurized commercial products are generally safe.

6. Organ Meats
Liver and kidney are rich in nutrients like iron, vitamin B12, vitamin A, zinc, selenium, and copper, all beneficial during pregnancy. However, excessive intake of preformed vitamin A can cause birth defects and miscarriage, particularly in the first trimester. Moderation is key.

7. Caffeine
Coffee, tea, soda, and cocoa contain caffeine, which, in excess, may increase the risk of miscarriage, stillbirth, low birth weight, and developmental issues. Caffeine passes easily through the placenta, and the fetus cannot metabolize it efficiently. The American College of Obstetricians and Gynecologists (ACOG) recommends limiting caffeine intake to under 200 mg per day.

8. Raw Sprouts
Alfalfa, clover, and mung bean sprouts may harbor Salmonella. The moist environment needed for sprout growth also encourages bacterial growth, and washing cannot fully remove contamination. Cooked sprouts are safe.

9. Unwashed Fruits and Vegetables
Fruits and vegetables are healthy, but unwashed produce may carry bacteria and parasites like Toxoplasma, E. coli, Salmonella, and Listeria. Toxoplasma can cross the placenta, potentially causing vision or learning problems in the child, and in severe cases, eye or brain damage from birth. Wash thoroughly, peel, or cook before consumption.

10. Unpasteurized Dairy
Unpasteurized milk and dairy products may contain harmful bacteria such as Listeria, Salmonella, E. coli, and Campylobacter, leading to foodborne illness with potentially serious consequences for the fetus. Pasteurization kills these pathogens without reducing nutritional value.

11. Alcohol
Alcohol increases the risk of miscarriage and stillbirth, and even small amounts can negatively affect the baby’s brain. Drinking during pregnancy may cause fetal alcohol syndrome, including facial abnormalities, heart defects, and intellectual disabilities. No safe level has been established, so total avoidance is recommended.

12. Certain Juices and Smoothies
Fresh juices and smoothies can be healthy, but pregnant women should opt for pasteurized, sugar-free options. Unpasteurized juices, especially from juice bars, may carry harmful bacteria.

13. Highly Processed Foods
Processed foods are usually low in nutrients but high in calories, sugar, and unhealthy fats, which can lead to excessive weight gain. While some weight gain is essential during pregnancy, too much can increase the risk of delivery complications and childhood obesity.

For more guidance on keeping both mother and baby healthy, read our article on the essential dos and don’ts of pregnancy.