What's safe, and what helps, in early pregnancy?

The first trimester is when the baby's brain, spine and major organs form, so it's the stretch where a few things matter most. Most of it is simple.

Your prenatal vitamin

Food

• No extra calories are needed in the first trimester — about 340 more a day in the second and 450 in the third.
• Safety consideration Avoid unheated deli meats and hot dogs (heat until steaming), unpasteurized milk and soft cheeses such as queso fresco, premade deli salads, refrigerated pâté and smoked fish, raw sprouts, and raw fish or sushi.
• Fish is still good for you — 2–3 servings a week of low-mercury fish, and limit albacore tuna to 6 ounces a week. The fish list.
• Moderate evidence Caffeine under about 200 mg a day. What's in what.
• Strong evidence No alcohol. There's no known safe amount or safe time in pregnancy.
• Safety consideration No cannabis. ACOG advises against it in pregnancy and says there's no medical reason to use it.

Medications

• Check everything you take — prescriptions, over-the-counter medicines, herbs and supplements. Bring the bottles to your first visit.
• Acetaminophen (Tylenol) for pain or fever. ACOG and the Society for Maternal-Fetal Medicine consider it appropriate in pregnancy, used at the lowest dose that works for the shortest time. In September 2025 the federal government announced a label change over a possible link to autism; the FDA's own letter said a causal link hasn't been established, and ACOG said the announcement isn't backed by the full body of evidence. As of September 2026 the label hadn't changed. Untreated fever carries its own risks, so ask your doctor rather than going without.
• Safety consideration Avoid ibuprofen, naproxen and other NSAIDs from 20 weeks unless your doctor advises otherwise — they can affect the baby's kidneys. Low-dose aspirin prescribed for preeclampsia is the exception.

Nausea

It affects about 70% of pregnancies. Strong evidence Vitamin B6 is a safe first step, and doxylamine (a sleep aid) can be added if B6 alone doesn't work; there's also a combined prescription. Ginger can help too. Call if you can't keep fluids down, your urine is small and dark, or you feel dizzy or faint when you stand — that can be hyperemesis gravidarum, which needs treatment.

Movement and heat

• Strong evidence About 150 minutes a week of moderate activity if your pregnancy is uncomplicated. Avoid contact sports, anything with a risk of falls, and scuba diving.
• Safety consideration Avoid overheating, especially in the first trimester. Skip hot yoga, hot tubs and saunas; high body temperature early in pregnancy is linked to neural tube defects.

Weight gain over the whole pregnancy

For one baby. Most of it comes in the second and third trimesters.

Call right away if

• You have heavy bleeding, severe belly pain, pain on one side, or pain in the tip of your shoulder.
• You feel dizzy or faint.
• You have a fever of 100.4°F or higher.
• You can't keep fluids down for 8 hours or more.
• You have trouble breathing, chest pain, or a racing heart.
• You have thoughts of harming yourself or your baby — call or text 1-833-TLC-MAMA (1-833-852-6262), free and confidential, any time.