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• What Is Prenatal Care Before Pregnancy?

  What should women who are planning a pregnancy do before they conceive? Find out here.

• What if My Baby Isn’t Born by My Due Date?

  Find out what the experts have to say.

• What’s a “High-Risk” Pregnancy?

  Find out what the experts have to say.

• When Do Pregnant Women Need Progesterone Shots?

  Doctor may prescribe progesterone shots during a woman's pregnancy to help prevent early labor.

• Why Are Babies Born Early?

  Many things can cause a baby to be born early or with health problems. Some of these things can be controlled, but others can’t. Find out what you can do to have a healthy pregnancy.

• Why Are Pregnant Women Told to Avoid Feta Cheese?

  Find out what the experts have to say.

• Why Do Many Pregnant Women Pull Ligaments, Muscles, and Joints?

  Find out what the experts have to say.

• Why Do Some Pregnant Women Get Varicose Veins?

  Find out what the experts have to say.

• Why Do Some Women Feel Short of Breath During Pregnancy?

  As a normal part of pregnancy, breathing may be affected by the increase in the hormone progesterone, which causes you to breathe in more deeply. This might make you feel as if you're working harder to get air.

• Your Newborn

  Advice and information for new parents.

• Week 24

  Your baby's inner ear has developed enough that your baby can know when he or she is upside down or right side up in your belly.

• Week 25

  You may notice that your baby has resting and alert periods. Your baby's hearing has continued to develop, too — he or she may now be able to hear your voice!

• Week 26

  Your baby now weighs a little less than 2 pounds and will gain weight steadily until birth.

• Week 27

  This first week of the third trimester, your baby looks similar to what he or she will look like at birth - just smaller and thinner.

• Week 28

  Your health care provider may tell you whether your baby is headfirst or feet- or bottom-first (called breech position). Don't worry if your baby is in the breech position right now — most babies will switch positions on their own.

• Week 29

  Your active baby's first few flutters of movement have given way to hard jabs and kicks that may take your breath away.

• Week 3

  During this week, the rapidly dividing fertilized egg will implant itself in the uterus, at the site that eventually will become the placenta.

• Week 30

  Your baby continues to gain weight and layers of fat that will provide warmth after birth.

• Week 31

  By now, the milk glands in your breasts may have started to make colostrum, the milk that will feed the baby in the first few days if you decide to breastfeed.

• Week 32

  At this stage in the pregnancy, your baby's hair is developing, in the form of eyelashes, eyebrows, and on your baby's head.

• Week 33

  Like a newborn, your baby sleeps much of the time and even has REM sleep, the stage when our most vivid dreams happen.

• Week 34

  Your baby is probably in position for delivery — your health care provider can tell you if your baby is positioned head- or bottom-first.

• Week 35

  Because of increasing size, your baby is now cramped and restricted inside the uterus. Fetal movements may decrease, but feel stronger and more forceful.

• Week 36

  At this point, your appetite may return because the baby has dropped down into your pelvis, and is no longer putting as much pressure on your stomach and intestines.

• Week 37

  This week, your baby continues to gain weight — at half an ounce a day!

• Week 38

  At this point, you may be taking frequent trips to the bathroom. That's because your baby is engaged in your pelvis, so your bladder is extremely compressed.

• Week 39

  Braxton Hicks contractions (also called "false labor") may become more pronounced, and your water may break.

• Week 4

  During this week, your baby, or embryo, has two layers of cells that will develop into organs and body parts.

• Week 40

  Your baby is here! Or maybe not — most women, especially first-time moms, don't deliver on their estimated due dates.

• Week 5

  This week, the embryo begins to form a distinct shape that includes the neural tube, which will become the spinal cord and brain.

• Week 6

  Your baby's heart will begin to beat around this time, and the beginnings of the digestive and respiratory systems are forming, as are small buds that will grow into arms and legs.

• Week 7

  The umbilical cord has formed, and the mouth, nostrils, ears, and eyes are some of the facial features that become more defined this week. The arm bud now has a hand on the end of it, which looks like a tiny paddle.

• Week 8

  Around this time, symptoms such as a missed period, nausea, extreme fatigue, or tight clothes may make the reality of pregnancy hit home.

• Week 9

  Your baby measures about 0.6 to 0.7 inches from crown to rump and weighs around 0.1 ounces. Your baby may make some first movements as muscles develop, but you won't feel them for several more weeks.

• What Are Kegel Exercises?

  Doing Kegel exercises during pregnancy can help reduce incontinence (when pee leaks) caused by the weight of the baby on the bladder.

• What Can I Do to Relieve My Pregnancy Backaches?

  Find out what the experts have to say.

• Treatments to Prevent Premature Birth

  Some women are more likely than others to go into labor early. Find out what doctors can do to help prevent or delay early labor.

• Using Artificial Sweeteners During Pregnancy

  Most FDA-approved low-calorie sweeteners are OK to use in moderation during pregnancy. Find out more.

• Using Bug Killers and Repellents During Pregnancy

  Some pesticides can harm a growing fetus. But many insect repellents are considered safe to use during pregnancy.

• Using Hair Dyes and Color During Pregnancy

  Because very little dye is absorbed through the skin, dying your hair is "most likely usually safe" during pregnancy, say health experts.

• Using Household Chemicals During Pregnancy

  Using some household chemicals may have no effect during pregnancy, while others in high doses could be harmful.

• Using Medicines During Pregnancy

  Many medicines shouldn't be used during pregnancy, but others are OK.

• Using Teeth Whiteners During Pregnancy

  If you're pregnant, talk to your doctor or dentist before using bleaching products.

• Week 1

  Week 1 is actually your menstrual period, but because your due date is calculated from the first day of your last period, it counts as part of your 40-week pregnancy.

• Week 10

  At this point in the pregnancy, all vital organs have been formed and are starting to work together. Congenital abnormalities are unlikely to develop after week 10.

• Week 11

  If you saw a picture of your baby now, you'd think you had a genius on your hands — the baby's head accounts for about half of the body length!

• Week 12

  Tiny fingernails and toenails start to form this week, which is the last of your first trimester.

• Week 13

  As you begin the second trimester, your baby may be able to put a thumb in his or her mouth although the sucking muscles aren't completely developed yet.

• Week 14

  Some fine hairs, called lanugo, have developed on your baby's face. This soft colorless hair protects the skin and will eventually cover most of your baby's body until it is shed just before delivery.

• Week 15

  Muscle development continues, and your baby is probably making lots of movements with his or her head, mouth, arms, wrists, hands, legs, and feet.

• Week 16

  Your baby can hold his or her head erect, and facial muscles now allow for a variety of expressions, such as squinting and frowning.

• Week 17

  Your baby is still very tiny at about 5.1 inches from crown to rump this week.

• Week 18

  Your baby's bones had been developing but were still soft. This week, they begin to harden, or ossify.

• Week 19

  A waxy substance called vernix caseosa is covering your baby to help protect the delicate skin from becoming chapped or scratched.

• Week 2

  Week 2 is the midpoint of a typical menstrual cycle, when ovulation occurs and conditions are most favorable for fertilization of an egg by sperm.

• Week 20

  You're now halfway through your pregnancy and possibly feeling your baby's first movements, which may begin between weeks 18 and 20.

• Week 21

  Your baby's intestines are developed enough that small amounts of sugars are absorbed from the fluid your baby swallows and passed through the digestive system to the large bowel.

• Week 22

  Brain and nerve endings are formed enough so that the fetus can feel touch, while you might be feeling irregular, painless Braxton Hicks contractions.

• Week 23

  You may feel more forceful movements — your baby's daily workout routine includes moving the muscles in the fingers, toes, arms, and legs.

• Prenatal Test: Nonstress Test

  This test checks to see if the baby responds normally to stimulation and is getting enough oxygen. It's done to check on the health of the fetus in a high-risk pregnancy or when the due date has passed.

• Prenatal Test: Percutaneous Umbilical Blood Sampling (PUBS)

  This quick test examines fetal blood directly from the umbilical cord. It's used to detect disorders in the fetus.

• Prenatal Test: Ultrasound

  A prenatal ultrasound is a safe and painless test that shows a baby's shape and position. It can be done in the first, second, or third trimester of pregnancy.

• Prenatal Tests: FAQs

  Every parent-to-be hopes for a healthy baby, but it can be hard not to worry. Find out what tests can keep you informed of your health — and your baby's — throughout pregnancy.

• Prenatal Tests: First Trimester

  Find out what tests may be offered to you during the first trimester of pregnancy.

• Prenatal Tests: Second Trimester

  Find out what tests may be offered to you during weeks 13 through 26 of pregnancy.

• Prenatal Tests: Third Trimester

  Find out what tests may be offered to you during weeks 27 through 40 of pregnancy.

• Preparing for Multiple Births

  Are you expecting more than one baby? Find out how to take care of yourself and prepare for your multiple birth experience.

• Preventing Overheating During Pregnancy

  Find out why it's important to keep your core temperature at a normal level and not get overheated during pregnancy.

• Preventing Premature Birth

  Babies who are born premature — before 37 weeks of pregnancy — can have health problems that last their whole lives. Learn ways to prevent early labor and have a healthy pregnancy.

• Recovering From Delivery

  After giving birth, you'll notice you've changed somewhat - both physically and emotionally. Here's what to expect after labor and delivery.

• Recreational Drugs and Pregnancy

  Drug use during pregnancy can cause many problems, both in the mother and baby.

• Rh Incompatibility During Pregnancy

  If you just found out you're pregnant, one of the first tests you should expect is a blood-type test. This basic test determines your blood type and Rh factor, which may play an important role in your baby's health.

• Severe Morning Sickness (Hyperemesis Gravidarum)

  Bouts of nausea and vomiting during pregnancy are considered normal. But when they're so severe that a woman can't keep foods down, she and her baby's health are at risk.

• Sex During Pregnancy

  Like many parents-to-be, you might have questions about the safety of sex and what's "normal." That can vary widely, but you can be sure that your sex life will change during pregnancy.

• Sleeping During Pregnancy

  Catching enough ZZZs during pregnancy can be difficult for many women. Here's why - plus tips for better sleep.

• Smoking and Pregnancy

  Especially during pregnancy, it’s best to avoid all tobacco or nicotine-containing products. Here's why.

• Staying Healthy During Pregnancy

  During your pregnancy, you'll probably get advice from everyone. But staying healthy depends on you - read about the many ways to keep you and your baby as healthy as possible.

• Sunless and Self-Tanning During Pregnancy

  It hasn’t been that well-studied, but there's no proof that self-tanners are harmful to an unborn baby.

• Taking Care of Your Mental Health During Pregnancy

  Pregnancy brings a mix of feelings, and not all of them are good. It can be even harder if you're dealing with depression or anxiety.

• How Can I Deal With Heartburn During Pregnancy?

  Find out what the experts have to say.

• How Can I Relieve My Pregnancy Leg Cramps?

  Find out what the experts have to say.

• I’m Pregnant. How Can I Avoid Having My Baby Early?

  Find out what the experts have to say.

• Inducing Labor

  Find out why doctors may induce labor if you're past your due date, how it may be done, and how it may affect you and your baby.

• Is it Safe to Clean a Cat’s Litter Box During Pregnancy?

  During pregnancy, it's best to have someone else clean kitty's litter box. Here's why.

• Medical Care During Pregnancy

  The sooner in pregnancy good care begins, the better for the health of both moms and their babies. Here's what to expect.

• Natural Childbirth

  Some women choose to give birth using no medications at all, relying instead on relaxation techniques and controlled breathing for pain. Get more information on natural childbirth.

• Neonatal Abstinence Syndrome (NAS)

  Neonatal abstinence syndrome (NAS) is when a baby has withdrawal from a medicine or drug the mom took while she was pregnant.

• Postpartum Depression

  It's important for new mothers – and those who love them – to understand the symptoms of postpartum depression and reach out to family, friends, and medical professionals for help.

• Pregnancy Center

  Advice and information for expectant parents.

• Pregnancy Precautions

  There can be a lot of questions about what's safe during pregnancy. Find out what's OK and what you should avoid before your baby is born.

• Pregnancy Slideshow (Baby)

  This week‑by‑week pregnancy calendar shows you some of the important developments taking place as your baby grows.

• Pregnancy Slideshow (Mom & Baby)

  Here's a peek at what's going on inside your body during the amazing 40 weeks of pregnancy. Watch your belly — and your baby — grow!

• Pregnant or Breastfeeding? Nutrients You Need

  Learn which nutrients you need while pregnant or breastfeeding, and easy ways to add them to your diet.

• Prenatal Test: Amniocentesis

  In amniocentesis, doctors take a sample of the amniotic fluid that surrounds a baby to check for signs of problems such as chromosomal disorders, genetic problems, and neural tube defects

• Prenatal Test: Chorionic Villus Sampling (CVS)

  A chorionic villus sampling (CVS) checks cells from the placenta for chromosomal abnormalities. Most women whose pregnancies are not high-risk don't need this test.

• Prenatal Test: Contraction Stress Test

  A contraction stress test measures the fetal heart rate to ensure that a baby can handle contractions during labor.

• Prenatal Test: First Trimester Screening

  The first trimester screening (or first trimester screen) includes a blood test and an ultrasound exam. It's done to see if a fetus is at risk for a chromosomal abnormality or birth defect.

• Prenatal Test: Glucose Screening

  Glucose screenings check for gestational diabetes, a short-term form of diabetes that some women develop during pregnancy.

• Birth Plans

  The reality of labor and birth may seem extremely far off - but now's the time to start planning for your baby by creating a birth plan that details your wishes.

• Birthing Centers and Hospital Maternity Services

  Where you choose to give birth is an important decision. Is a hospital or a birth center right for you? Knowing the facts can help you make your decision.

• Bringing Your Baby Home

  Whether your baby comes home from the hospital right away, arrives later, or comes through an adoption agency, homecoming is a major event.

• Can I Have a Vaginal Birth If I Had a Previous C-Section?

  Find out what the experts have to say.

• Can Pregnant Women Do Anything to Reduce or Prevent Swollen Ankles?

  Find out what the experts have to say.

• Cesarean Sections (C-Sections)

  Many babies are delivered via cesarean sections. Learn why and how C-sections are done.

• Coffee and Caffeine Use During Pregnancy

  It's usually OK to have 1 or 2 cups of coffee during pregnancy, but it's best to not have more than that. Find out more.

• Cord Blood Banking

  Should you bank your newborn's cord blood? This article can help you decide.

• Coronavirus (COVID-19): Pregnancy FAQs

  We're learning more every day about coronavirus (COVID-19). Here are some answers to questions about coronavirus and pregnancy.

• Dealing With Pain During Childbirth

  Learning all you can about childbirth pain is one of the best ways to help you deal with it when the time comes.

• Drinking Tap Water During Pregnancy

  Bottled water might taste better or different than tap water, but it isn’t necessarily any safer during pregnancy.

• Eating During Pregnancy

  To eat well during pregnancy, your extra calories should come from nutritious foods that contribute to your baby's growth and development.

• Ectopic Pregnancy

  In an ectopic pregnancy, a fertilized egg has implanted outside the uterus, usually in the fallopian tubes. If undiagnosed, as the pregnancy grows, it can burst the organ that contains it and endanger the mother's life.

• Epidurals

  Epidurals can make giving birth more calm, controlled, and comfortable. Find out more.

• Exercising During Pregnancy

  Most women benefit greatly from exercising throughout their pregnancies. But during that time, you'll need to make a few changes to your normal exercise routine.

• Folic Acid and Pregnancy

  One of the most important ways to help prevent serious birth defects is for moms to get enough folic acid every day - especially before conception and during early pregnancy.

• Food Safety During Pregnancy

  Find out which foods and drinks to avoid during pregnancy.

• Getting X-Rays During Pregnancy

  If you're pregnant and need to get an X-ray, it's highly unlikely that low levels of X-ray radiation will be harmful.

• Group B Strep and Pregnancy

  Women who have this common but potentially dangerous bacteria while pregnant get antibiotics during labor to avoid passing the bacteria to their babies.

• High-Impact Exercising During Pregnancy

  Most moms-to-be benefit greatly from exercising. But there are some types to avoid during pregnancy.

• 10 Things That Might Surprise You About Being Pregnant

  Here are 10 common surprises that can come with pregnancy.

• 5 Things to Know About Zika and Pregnancy

  Zika virus, spread by mosquitoes, is the cause of a serious birth defect. Here are 5 things to know about Zika and pregnancy.

• 5 Ways to Prevent Early Labor (Slideshow)

  It's best for babies not to be born before they're due. Learn what you can do to prevent early labor.

• A Guide for First-Time Parents

  If you're a new parent, get the basics in this guide about burping, bathing, bonding, and other baby-care concerns.

• A Week-by-Week Pregnancy Calendar

  Our week-by-week illustrated pregnancy calendar is a detailed guide to all the changes taking place in your baby - and in you!

• Air Travel During Pregnancy

  Most healthy pregnant women can fly up to 4 weeks before their due date. After that, it's best to stay close to home in case you deliver.

• Alcohol Use During Pregnancy

  It's always wise to be cautious and not drink any alcohol at all during pregnancy. Here's why.

• Are Vaccines Safe During Pregnancy?

  Be sure to talk to your doctor before getting any vaccination during pregnancy. It's best to wait until after your pregnancy for most vaccines, but a few are considered safe.

• Are You in Labor?

  Here's how to tell the difference between true labor and false labor -- and when to get medical care.

• Avoiding Lead Exposure During Pregnancy

  Lead is toxic and especially harmful for a developing fetus. Fortunately, exposure to high lead levels is rare in the United States.

• Gestational Diabetes

  Gestational diabetes is a kind of diabetes that comes on during pregnancy. When a woman has it, her blood sugar levels are high. That makes the unborn baby's blood sugar levels higher too.

• Intrauterine Growth Restriction (IUGR)

  Intrauterine growth restriction is when a baby in the womb doesn't grow at the expected rate during the pregnancy. Women with IUGR should eat a healthy diet; get enough sleep; and avoid alcohol, drugs, and tobacco.

• Miscarriages

  Miscarriages are common, and in most cases aren't preventable. But you can take steps to increase your chances of having a healthy pregnancy.

• Fetal Alcohol Syndrome (FAS)

  If a woman drinks alcohol during her pregnancy, her baby could be born with fetal alcohol syndrome (FAS), which causes a wide range of physical, behavioral, and learning problems.