First Trimester Checklist: What to Actually Do in Weeks 1-13

Two lines on a test and suddenly the internet has opinions about everything you eat, drink, lift, or lie down on. Most of it is noise. The actually-important first-trimester to-dos are pretty short, and they come from the same handful of places every OB will point you to.

This is that short list — the concrete things to do in weeks 1 through 13, each one traced back to MedlinePlus, the FDA, or the U.S. Office on Women's Health. Nothing invented in between.

01The 60-second version

02Book your first prenatal appointment now

This is the single most important thing on the list, and it does not need to wait until you feel pregnant. The U.S. Office on Women's Health lays out the standard visit rhythm — "once each month for weeks four through 28," then twice a month, then weekly — so the first-trimester version is essentially: one visit a month. MedlinePlus confirms the same: "In your first trimester, you will have a prenatal visit every month."

That first appointment tends to be the longest one you'll have — it is where your due date gets calculated, your medical history gets recorded, and the labs get ordered. If you have any conditions that could make this a higher-risk pregnancy (diabetes, high blood pressure, a previous pregnancy loss), MedlinePlus notes that care is often scheduled more frequently, so getting on the calendar early matters even more.

03Start (or keep taking) a prenatal vitamin

The point of a prenatal vitamin isn't the marketing — it's two nutrients: folic acid and iron. MedlinePlus puts the folic acid number plainly: "During pregnancy and when breastfeeding, you need 600 mcg per day from foods and/or vitamins," and adds that "it is hard to get this amount from foods alone, so you will most likely need to take a supplement that contains folic acid." The MedlinePlus first-trimester care page says your provider will give you "prenatal vitamins with iron if you are not already taking them."

If you find you can't keep the vitamin down in the queasy weeks, that is worth mentioning at your visit — providers can suggest a different formulation, splitting the dose, or taking it at bedtime. Do not just stop and wait; the folic acid work happens in these first weeks.

04The food-safety list, one time, so you can stop googling

The foods to skip in pregnancy are almost all about one thing: avoiding Listeria, a bacterium that grows even in the refrigerator and hits pregnant people harder than the general population. MedlinePlus names the specific ones to avoid: "Refrigerated smoked seafood like whitefish, salmon, and mackerel" and "Unpasteurized soft cheeses, such as unpasteurized feta, Brie, queso blanco, queso fresco, and blue cheeses." It also flags "Undercooked meat, poultry, eggs, and seafood."

Fish gets a special mention because it is genuinely good for pregnancy — but only the low-mercury kinds. The FDA/EPA advice, as summarized by USDA WIC Works, is to eat "2 to 3 servings a week of fish in the 'Best Choices' category, based on a serving size of four ounces." MedlinePlus is more specific about the high-mercury ones to avoid: "Do not eat tilefish, shark, swordfish, marlin, orange roughy, or king mackerel," and "Limit white (albacore) tuna to 6 ounces per week."

05Alcohol, tobacco, and the medicine cabinet

This one is short. MedlinePlus lists the substances to avoid in pregnancy as, straightforwardly, "alcohol, drugs, and tobacco." No amount of alcohol is considered safe in pregnancy — including that first-few-weeks stretch when you may not have known yet (which is worth telling your provider about, but is not something to spiral over).

The medicine-cabinet question is worth its own conversation at your first visit. Some prescription and over-the-counter medications are fine during pregnancy, some need a swap, and a few need to stop. Bring a list of everything you take — including supplements — to that appointment. Do not stop a prescribed medication (especially for anxiety, depression, thyroid, or seizures) on your own; talk to the provider who prescribed it.

06Keep moving — but don't overheat

For most healthy pregnancies, staying active is protective, not risky. MedlinePlus frames it plainly: "Physical activity can help you stay strong, feel and sleep better, and prepare your body for birth." Walking, swimming, prenatal yoga, and light strength work are all typically fine — but the first trimester is the one where overheating (from hot yoga, saunas, or hot tubs) is a specific concern, so save those for after.

If exercise wasn't already part of your routine, start gently. If something new starts hurting, or you feel dizzy or short of breath in a way that isn't normal for you, stop and mention it at your next visit. Any bleeding after exercise is a reason to call, not to wait.

07What actually happens at that first appointment

The first visit is longer than the ones that follow because it is really an intake. According to MedlinePlus, you can expect your provider to "ask about your health history, including prior pregnancies," "do a complete physical exam, including a pelvic exam and Pap test," review "blood, urine, or other routine prenatal lab tests," and "figure out your due date (when you are 40 weeks pregnant)." The Office on Women's Health adds that early first-trimester screening (weeks 11-14) is often offered at this stage as well.

Later in the first trimester — "by about 12 to 14 weeks of pregnancy" — many providers can pick up the baby's heartbeat with a small handheld device called a Doppler, according to Mayo Clinic. That is often the visit people describe as the one that made it feel real.

08The regular first-trimester discomforts (and what actually helps)

A lot of the first trimester is genuinely uncomfortable, and none of the symptoms below are on their own a sign that something is wrong. MedlinePlus covers the standard ones. The short version:

• Fatigue — the tiredness of early pregnancy is a different level than normal tired. MedlinePlus is direct about the fix: "Exercise, rest, and a proper diet can make you feel less tired." Nap when you can. This one usually eases in the second trimester.
• Frequent urination — starts early as the uterus grows. "You will continue to urinate more throughout pregnancy. That means you also need to drink more water," per MedlinePlus. Do not cut back on fluids; do plan bathroom stops.
• Heartburn — MedlinePlus suggests smaller portions, skipping spicy and greasy food, keeping liquids away from bedtime, waiting two hours after eating before exercise, and not lying flat right after meals. If it persists, ask about safe medications.
• Nausea and vomiting ("morning sickness") — usually starts around week 6 and often eases by weeks 12-14. Small, frequent, bland meals; keeping crackers by the bed; and staying hydrated help. It is worth calling your provider if you cannot keep fluids down.

09When to call — don't wait it out

Most of the first trimester is watchful waiting, but a few symptoms are calls, not texts. MedlinePlus lists the standard "contact your provider" flags:

• "You have a significant amount of nausea and vomiting."
• "You have bleeding or cramping."
• "You have increased discharge or a discharge with odor."
• "You have a fever, chills, or pain when passing urine."
• "You have any questions or concerns about your health or your pregnancy."

That last one is not throwaway advice. A five-minute nurse call is exactly what your OB office is set up to handle, and it will save you a night of googling. If something feels wrong, call.

10One trimester at a time

The first trimester is mostly a stretch of small decisions and one big change nobody else can see yet. There is no baby room to build, no bag to pack, no name that needs to be final. Just: get on the schedule, take the vitamin, skip the short list of foods, and be honest with your provider about how you're feeling.

When you're ready for what comes next, our second trimester and beyond planner walks the same weekly rhythm all the way through — and our third trimester checklist and nesting-during-pregnancy guide pick up when the to-dos start to get physical. If you want the whole-pregnancy view in one place, the pregnancy checklist links every stage together.

Questions parents actually ask

Newborn Weeks is planning help, not medical advice — always follow your own doctor, midwife, or pediatrician.