Pregnancy happens when an egg is fertilized by a sperm, and that fertilized egg gets implanted into the wall of the uterus.
Check out this video for a primer on how pregnancy happens.
A full pregnancy lasts about 40 weeks. Sometimes, babies are born earlier or later; a baby born before 37 weeks is considered preterm. Pregnancy is usually broken down into three parts or trimesters.
This trimester is when the baby’s organs develop. You may feel incredibly tired, sick, or moody, but everyone experiences pregnancy differently. If you haven’t already, this is a good time to learn about the best ways to have a healthy pregnancy and what to watch for.
Most pregnant parents who experienced symptoms in the first trimester tend to feel better during these months. But you may also start to feel more aches and pains as the baby and your belly grow. You should start to feel your baby kicking around week 16.
This is the home stretch. Your baby will be pretty active in your belly and should start to turn itself head-down. Toward the end of the third trimester, you might feel uncomfortable. Your growing uterus can cause symptoms like heartburn, shortness of breath, and frequent urination.
When you’re pregnant, trying to get all the information you need can be overwhelming. There’s a lot to understand about what is going on in your body, and on top of that, there’s a lot to learn about how to keep the baby safe and healthy. The good news is, we’ve got you covered, from symptoms to supplements to frequently asked questions.
For many people, the first sign of pregnancy is a missed period. But if your periods are irregular to begin with, this isn’t very reliable. Other early symptoms include breast tenderness, feeling more tired than usual, and nausea.
You can start to feel pregnant as soon as 1 week after conception. You may also have mood changes, bloating, and light spotting around the time of implantation, which is around 10 to 14 days after conception.
The first trimester is interesting because although you don’t “look” pregnant, you will almost certainly feel pregnant. This isn’t an exhaustive list, but here are some of the symptoms you may have:
Nausea and vomiting
Know that everyone experiences pregnancy in a different way. While it’s sometimes helpful to ask your friends and family what to expect, their advice might not reflect what’s going on with your body.
Urine pregnancy tests — both over the counter and at your healthcare provider’s office — work by checking for a hormone called human chorionic gonadotropin (HCG). This hormone isn’t present until the fertilized egg is implanted into your uterine wall.
Urine pregnancy tests are most accurate when taken after your first missed period or around 3 weeks after you had sex (if your periods aren’t regular).
After a positive urine pregnancy test at home, it’s important to make an appointment with an obstetrician or other women’s health provider. At this visit, they will confirm your pregnancy with an ultrasound and help you determine a due date. If all goes well, you may get to hear your baby’s heartbeat for the first time!
Your provider will talk to you about any additional testing that needs to be done. Examples include:
Urine tests: to check for infection and levels of glucose and protein
Blood tests: to check for anemia and determine your blood type
Vaginal swab: to check for sexually transmitted infections
If you have any medical conditions that can affect your pregnancy, this might be a good time to get those checked as well. For example, if you have hypothyroidism, your regular dose of thyroid medication might need to be adjusted. Your provider will check your thyroid hormone levels regularly throughout your pregnancy.
Vitamins and supplements are super important in pregnancy. Special prenatal formulations contain all the vitamins and minerals necessary to help you and your growing baby get the nutrition you need. Plus, taking a prenatal vitamin has been linked to a lower risk of miscarriage. There are a lot of brands out there, so it’s best to check with your provider for recommendations.
Folic acid is the most important supplement to take before and during pregnancy. This reduces the risk of serious birth defects called neural tube defects. The recommended amount for most pregnant women is 400 mcg per day. For those with a previous pregnancy affected by a neural tube defect or with a seizure disorder, the recommendation is to take 4 mg of folic acid daily. If you’re not sure which dose is right for you, your obstetrician can help.
At your first visit, expect your provider to discuss vaccinations with you. It’s recommended that pregnant women get the flu shot, as well as a booster against pertussis (whooping cough). Depending on where you work or travel, you might need additional vaccines.
Your prenatal appointments are great opportunities to ask any questions, so don’t be shy. In addition to answering your questions, your provider will give you recommendations for what to eat, what to avoid, and what to watch for. (Read here about foods to avoid in pregnancy.)
Many women are concerned about taking medications while they are pregnant, and rightfully so. Medicines can affect the baby’s development or cause miscarriage. Examples of birth defects caused by medications include cleft lip and cleft palate, which are not life-threatening, but more severe heart or brain problems are possible.
The problem is, it’s really hard to tell if a birth defect is caused by a medication, or if it would have happened without the medication. Birth defects occur in as many as 3% of births in the U.S., so it’s already a small risk. Plus, it isn’t ethical to conduct research studies on pregnant women, so the data is limited.
Previously, the FDA created categories to describe medication safety during pregnancy. But they decided to change that system in 2015 to make the information clearer. Now, each drug label has a section dedicated to safety in pregnancy, and you can search the FDA database for any drug to read its label, including information on safety in pregnancy. These tools allow healthcare providers and patients to better understand the risks of each drug, so they can make informed decisions.
In general, less is more when it comes to taking medications — both prescription and over the counter — in pregnancy. But there are many situations when medications are needed to keep you healthy. In these cases, you and your provider will need to weigh the benefits of a medication against the risks — based on the evidence available.
Vaginal bleeding in pregnancy isn’t necessarily a bad sign. It depends on the context — how far along you are in your pregnancy, how much blood you are losing, and whether you’re having other symptoms, like a fever or pain. Bleeding in the first trimester happens in up to 25% of pregnancies, and it’s usually not serious.
The general rule is that you should see your provider if you have bleeding while you are pregnant — at any time — because it could signal one of the following:
Problem with the placenta
Preterm (early) labor
Early pregnancy loss, or miscarriage, happens in up to 15% of pregnancies. Experts believe that in most cases, it’s because of a problem with the baby’s chromosomes. When the sperm and egg join in fertilization, sometimes the embryo ends up with the wrong number of chromosomes. This means the baby has severe defects that don’t allow it to survive.
Miscarriage is not caused by working, exercising, or having sex while you’re pregnant.
Sometimes, medical problems can happen that make pregnancy more complicated. That’s why it’s important to have regular check-ups with your obstetrician or other healthcare provider during a pregnancy. Many complications can be detected with physical examinations, blood and urine tests, and ultrasounds.
In other words, by getting regular prenatal care, you can stay on top of any problems that may pop up and get treatment when needed.
Some examples of pregnancy complications include:
Pregnancy-induced high blood pressure
Preeclampsia and eclampsia, which are life-threatening organ damage due to high blood pressure
Hyperemesis gravidarum, which is severe nausea and vomiting of pregnancy
Ectopic pregnancy, which is pregnancy that happens outside the uterus
Placenta previa, which happens when implantation of the placenta is too low
Yes, it is possible to get a UTI, or urinary tract infection, during pregnancy. If you have a burning sensation when you pee, or if you need to go more than normal, speak to your provider. They can test your urine to see if you have a UTI and prescribe antibiotics if so.
It’s important to treat UTIs in pregnancy, because they can cause health problems for both mom and baby if not treated.
Vaginal delivery is not a surgery like a cesarean delivery, or C-section, so there are fewer possible complications. The recovery tends to be shorter, as well. That said, a cesarean delivery might be necessary for several reasons. It’s important to know about each option as you near the end of your pregnancy.
We’ve got you covered if you want to learn more about vaginal delivery or C-section.
Yes, it’s common to have more discharge than normal in pregnancy. It may get heavier toward the end of your pregnancy, as well.
That said, it is possible to have an infection during pregnancy that could cause vaginal discharge. If you notice that your discharge changes in any of these ways, contact your provider:
Don’t use any sprays or douches, as they could irritate your vulva or vagina.
If a baby is born before 24 weeks of gestation, survival is unlikely.
While this is extremely rare, it is possible. Usually during pregnancy, eggs aren’t made or released so another pregnancy won’t happen.
You may feel all kinds of belly symptoms in the first trimester:
In the second trimester, you’ll probably feel like eating more, and your pregnancy bump will show. You’ll also get to experience that very unique feeling of the baby kicking. As your belly gets bigger, your skin might start to feel itchy and tight. The third trimester is when you can see and feel the baby moving around.
In some situations, a positive pregnancy test might not be good news. In fact, up to 45% of pregnancies in the U.S. in 2011 (the most recent data we have) were unintended. It might help to talk to someone you trust about your unexpected news, or visit your local family-planning clinic. You can also call this free hotline for peer support. Lots of online resources are available to learn more about your options, including parenting, adoption, or medical abortion.
All Options. (2021). All-options talkline.
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American College of Obstetricians and Gynecologists. (2019). Preterm labor and birth.
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