Your first trimester pregnancy checklist

What is the first trimester?

The first trimester is the first of three phases (or trimesters) of pregnancy. It's a critical stage in your pregnancy journey and your baby's development. While your baby bump may or may not be showing, a lot is happening for both you and your baby.

Your baby is growing rapidly – developing a brain and heart, forming facial features, and even growing tiny little feet, hands, fingernails, and toenails. In the first trimester, all of your baby's major organs and systems form. Because of this, your baby is the most vulnerable now to harm from alcohol, drugs, tobacco, some medications, and toxic substances. For more on your baby's development, see our images of fetal development by week.

At the same time, your body is changing and flooding with the pregnancy hormones hCG, estrogen, and progesterone. Hormonal changes may bring on unpleasant symptoms that are common during the first trimester, like nausea, vomiting, headaches, and extreme tiredness. Home remedies may help a bit, but if your symptoms are unbearable, let your provider know.

You'll choose a doctor or midwife to care for you and your baby, and you'll make several trips to see your provider. Each prenatal visit during the first trimester involves a similar routine: your provider will check your weight and blood pressure; answer your questions; order tests; take a urine sample; and either listen to your baby's heartbeat or see it on an ultrasound.

How long is the first trimester?

The first trimester begins at conception and lasts for 13 weeks, or three months. Month one spans from week one to week four of pregnancy; month two begins at week five and lasts until week eight; and the third and final month of the first trimester spans week nine through 13.

A funny thing about the first trimester is that you'll be a third of the way in before you even know you're pregnant. Because of the way pregnancy weeks are counted, conception happens when you're 2 weeks pregnant. By the time you take a home pregnancy test, you may be 4 or 5 weeks pregnant.

If you're not sure, visit our Pregnancy Due Date Calculator to check how many weeks pregnant you are.

First trimester symptoms

While some women have no pregnancy symptoms or mild symptoms during the first trimester, most experience some or all of the symptoms below.

Spotting and bleeding during the first trimester

You may notice spots of blood or light bleeding during the first few days or weeks of pregnancy. This is common, but it's a good idea to tell your provider so they can check that everything's okay.

Diarrhea in the first trimester

Loose or watery stools may arise during early pregnancy. They're usually not concerning, but persistent diarrhea can leave you dehydrated.

Headache in the first trimester

Hormonal changes may be responsible for first-trimester pregnancy headaches. They can also be brought on by stress, congestion, allergies, lack of sleep, or dehydration.

Cramping during the first trimester

You may not have expected cramping during pregnancy – just when you thought cramps were over! The usual culprit in early pregnancy is implantation, when the fertilized egg attaches to the uterus. Also, your uterus is expanding and adjusting to being pregnant, which can cause cramping early in pregnancy.

Back pain in the first trimester

Back pain tends to show up more in the second and third trimesters, but it's not uncommon to feel it during the first trimester.

First-trimester bloating

Burping and passing gas a lot more than usual? Gas and bloating is common during pregnancy because progesterone relaxes muscles throughout your body, including your digestive tract. This hormone slows the progress of food through your gut, giving healthy gut bacteria more time to produce gas from any given meal.

First-trimester insomnia

Some women have trouble falling asleep or wake frequently at night. Insomnia can start in early pregnancy and last until delivery, but a few adjustments can help you get better sleep.

First-trimester fatigue

You may be more exhausted than you ever imagined you could be. In early pregnancy, extreme fatigue is likely due to a dramatic rise in progesterone. Find out more about pregnancy fatigue, and learn the basics of good sleep during pregnancy.

Morning sickness

Unfortunately, "morning sickness" can last all day – and it strikes about three-quarters of pregnant women during the first trimester. If you have a mild case, some relatively simple measures can help. But if you're still suffering, talk with your provider about safe medications for morning sickness.

Discharge in the first trimester

You may notice an increase in vaginal discharge during the first trimester due to an increase in estrogen. It's usually harmless, but talk to your provider if you have pain, itching, or discharge that smells bad or looks unusual.

Sore breasts in the first trimester

Breast changes, including tender breasts and sore nipples, are usually one of the first signs of pregnancy. Thankfully, your breast will likely feel less sore by the end of the first trimester.

Constipation in the first trimester

Because progesterone slows movement in the digestive tract, things can get a little backed up. This can lead to constipation – try these tips to prevent and ease it.

Shortness of breath in the first trimester

During pregnancy, you need more oxygen – and this can lead to feeling out of breath. In the first trimester, shortness of breath may appear as a heightened awareness of the need to breathe. 

So many aches, pains, and strange feelings arise during pregnancy that it can be hard to decide what's normal and what's not. To complicate matters further, some symptoms may be more or less problematic depending on your particular situation or health history and on how far along you are in your pregnancy. But if you have any of these pregnancy symptoms, call your doctor or midwife immediately.

Weight gain in the first trimester

Gaining weight is a sign of a healthy pregnancy. Experts say it's normal to gain between one and five pounds in the first three months of pregnancy – though some women may gain more or less, or even lose weight during the first trimester due to morning sickness or other reasons.

Your provider will monitor your pregnancy weight to make sure you're in a healthy range and gaining at an appropriate pace. You can also use our Pregnancy Weight Gain Calculator to stay on track.

Don't worry if you can't eat a well-rounded diet in your first trimester – nausea and food aversions can make this feel impossible. Just do the best you can. Many women feel better eating small, frequent, carbohydrate-heavy snacks.

When you're able, make your pantry, fridge, and freezer pregnancy-friendly by filling them with healthy eats like nuts, fresh and dried fruit, multigrain pasta, and yogurt. Get a shopping list of healthy pregnancy foods.

During pregnancy it's especially important to avoid foods that could contain bacteria, parasites, or toxins – including undercooked meat, unpasteurized soft cheeses, anything that contains raw eggs, sushi made with raw fish, raw oysters, and fish that's high in mercury. Find out more about foods to avoid during pregnancy.

Sex during the first trimester

In your first trimester, you may feel too tired, moody, or nauseated to make love. But if you're feeling amorous (and you don't have any complications that may make sex dangerous), go ahead – you won't hurt the baby. The amniotic sac and the strong muscles of the uterus protect your baby, and the thick mucus plug that seals the cervix helps guard against infection.

Find out more about having sex during pregnancy.

First trimester pregnancy checklist

Use this list to keep track of all your first-trimester tasks, from making your first prenatal appointment to taking belly photos.

Take a prenatal vitamin

If you haven't started taking a prenatal vitamin yet, now's the time to start. It's particularly critical to get enough folic acid while trying to conceive and during your first trimester. Folic acid greatly reduces your baby's risk of developing neural tube birth defects such as spina bifida.

Investigate health insurance

Make sure you know what your health insurance plan covers as far as your prenatal care and delivery costs, as well as care for your new baby. Get answers to these questions by calling your health insurance company or talking to your company's benefits department. Or, find out what to do if you're pregnant and don't have health insurance.

Choose a doctor or midwife

If you already have a doctor or midwife you love, you're set. If not, you've got some homework to do. Talk to friends and relatives, ask one of your other providers to recommend someone, check out the preferred providers under your health insurance plan, or search online. Find out more about what to consider when choosing a doctor or midwife.

Make a prenatal appointment

To prepare for your first prenatal visit, jot down the first day of your last period and start making a list of any questions that arise. Talk to relatives on both sides about your families' medical histories. Your provider will want to know whether any chronic conditions or genetic abnormalities run in either of your families.

Get ready to see or hear your baby

At a prenatal visit around 9 to 12 weeks, you may get to hear your baby's heartbeat with the help of a Doppler fetal monitor. Many women say it sounds like galloping horses.

Some women have an ultrasound in the first trimester (though you may have to wait until between 16 and 20 weeks). If you do get to see your baby in the first trimester, don't be surprised if they look like a gummy bear or lima bean with a tiny, flickering heart.

Check your medications

Many medicines aren't safe during pregnancy – even some over-the-counter ones. If you take any medications, don't stop cold turkey. But do call your provider to find out if your medications are pregnancy-safe. Mention everything, even vitamins, supplements, and herbs.

Quit unsafe habits

Smoking during pregnancy, drinking alcohol, and using drugs like opioids and marijuana isn't safe for you or your baby during pregnancy. Talk to your provider and ask for help quitting if you need it. Also, some activities, jobs, and hobbies can be hazardous to you and your developing baby. Talk to your provider about what your daily routine involves, so you can come up with ways to avoid or eliminate hazards in your home and workplace.

Cut down on caffeine

It's a good idea to cut back on caffeine during pregnancy as much as you can, because it could affect your baby. Experts advise expectant moms to limit their caffeine during pregnancy to less than 200 mg per day (that's about one 11-ounce cup of coffee).

Consider your options for prenatal testing

During your first trimester, your provider will offer you various prenatal tests to check on the well-being of you and your growing baby. Some are routine and recommended for everyone, while others are left to your discretion. Genetic screening tests can give you information about your baby's risk for Down syndrome as well as other chromosomal problems and birth defects. NIPT (noninvasive prenatal testing) is available beginning at 10 weeks of pregnancy, and the nuchal translucency test (NT scan) can be done between 11 and 14 weeks.

Think about when and how you'll announce your pregnancy

Some expecting parents spill the beans to friends, family, and co-workers right away. Others wait to announce pregnancy until they're in their second trimester, when their pregnancy is well established and the risk of miscarriage has declined significantly.

Start taking belly photos

Have someone take a picture of you every week, or take your own picture using your reflection in a mirror. It's a great way to see your progress, and you'll love having the keepsake. Tips for a great shot: Consider wearing the same outfit, standing in the same spot, and striking the same pose (profiles work best) for each photo. For inspiration, check out our pregnant bellies photo gallery.

Follow your baby's development

Sign up for BabyCenter's free email newsletters and each week you'll learn exactly what's going on with both your pregnancy and your baby.

Join your Birth Club

Nobody understands what you're going through as well as other expecting moms in the same stage of pregnancy. Connect with women due the same month as you in your BabyCenter Birth Club.

Learn more:

• I'm pregnant: What do I do now?
• Second trimester guide and pregnancy checklist
• Third trimester guide and pregnancy checklist