Pregnancy Facts and Statistics: What You Need to Know

It takes about 40 weeks for a pregnancy to go from conception to delivery. In the United States, there were 3,659,289 live births in 2021. That's up 1% from 2020, the first increase since 2014.

This article highlights some important facts and statistics you should know about pregnancy.

Cropped shot of pregnant woman touching her belly and lower back.

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Overview of Pregnancy

Counting from the first day of your last period, pregnancy is expected to last about 40 weeks. A term pregnancy is when delivery occurs between 37 and 42 weeks. The stages of pregnancy are as follows:

  • First trimester: During weeks one through 12, hormonal changes affect almost every organ system in your body.
  • Second trimester: During weeks 13–27, your abdomen begins to expand, and you start to feel the baby move.
  • Third trimester: In weeks 28–42, the baby continues to grow and gain weight, so you'll feel more pressure on your organs. As your body prepares to give birth, the cervix thins and softens.


After your pregnancy ends, you'll need time to recover. Everyone is different, but you'll likely experience many physical and emotional changes in the first six weeks.

Maternal Age

In 2021, U.S. birth rates declined for women age 15–24 and rose for those age 25–49. Female fertility is at its peak between the late teens and late 20s. Fertility starts to decline by age 30. It declines even faster from your mid-30s to age 45. Births in 2021 included:

Number of Births Maternal Age
1,113,678 30–34
1,022,541 25–29
647,505 20–24
591,377 35–39
126,138 40–44
111,269 18–19
35,487 15–17
9,418 45–54
1,876 10–14

Teen Births

The 2021 birth rate for teens age 15–19 was 4.4 births per 1,000 females. That's a decrease of 6% from 2020. The rate of teen births in 2020 was down 75% from 1991. Still, the teen birth rate in the United States is higher than that of Canada, the United Kingdom, and many other developed countries.


In 2021, 32.1% of infants in the United States were delivered by cesarean section (C-section), a surgical delivery. The low-risk C-section rate rose to 26.3%. Multiple births aren't uncommon, as figures from 2020 show:

  • Twin births: 112,437
  • Triplet births: 2,738
  • Quadruplet and other higher order births: 137
  • Twin birth rate: 31.1 per 1,000 live births
  • Triplet or higher order birth rate: 79.6 per 100,000 live births

Pregnancy Loss

Losing a baby at or after 20 weeks of pregnancy is called a stillbirth. This happens in about 1 in 160 births. In the United States, about 24,000 babies are stillborn each year. Pregnancy loss, or miscarriage, is when a baby dies in the womb before the 20th week of pregnancy.

There's no way to know the total number of miscarriages since this can happen before you know you're pregnant. Among women who know they're pregnant:

  • About 10 to 15 in 100 pregnancies end in miscarriage.
  • Most miscarriages occur before the 12th week.
  • About 1 to 5 in 100 pregnancies end in miscarriage during the second trimester.
  • About 1 in 100 women have repeat miscarriages.
  • Many people who miscarry go on to have a successful pregnancy.

Risks and Complications

In the United States, there are about 50,000 unexpected labor and delivery outcomes each year. These outcomes have serious short- and long-term health consequences for both mother and baby. Here are some facts you should know:

  • The preterm birth rate increased by 4% in 2021 to 10.48%. That's the highest rate since 2007.
  • The preterm birth rate among Black women is 51% higher than for all other women.
  • Babies of teen mothers are at higher risk of low birth weight, preterm delivery, and severe neonatal conditions.
  • Most women in their late 30s and 40s deliver healthy babies. But as you age, the chances of having a baby born with a birth defect increase.
  • Mothers between the ages of 10 and 19 are at higher risk of certain complications than mothers between 20 and 24 years. These include eclampsia, inflammation and infection of the uterine lining (postpartum endometritis), and systemic (body-wide) infections.
  • Pregnant women over 40 are at increased risk of preeclampsia.

Postpartum Depression

Postpartum depression is a common complication for women who have recently given birth. If you're having trouble coping in the weeks and months after giving birth, call your healthcare provider right away. Postpartum depression is a serious medical condition, but it can be treated.

Maternal Mortality

Worldwide, complications of pregnancy and childbirth are the leading cause of death for 15- to 19-year-olds.

Each year in the United States, about 700 people die during pregnancy or the following year.And rates increase with maternal age. Black women are 3 times more likely than White women to die from pregnancy-related causes.

Contributing factors may include:

  • Differences in the quality of health care
  • Underlying chronic conditions
  • Structural racism and implicit bias

Infant Mortality

Infant mortality refers to the death of an infant before their first birthday. In 2020, the infant mortality rate in the United States was almost 542 infant deaths per 100,000 live births. That's a decrease of 2.9% from 2019. Some leading causes were:


After your pregnancy ends, your body will continue to change. Post-pregnancy changes in the first six weeks may include:

Prenatal Care

Prenatal care is the health care you get during your pregnancy. An estimated 14.9% of women have inadequate prenatal care. This is defined as starting in the fifth month or later or having less than half the recommended number of visits.

Babies of mothers who don't have prenatal care are 3 times more likely to have a low birth weight baby and are 5 times more likely to die than babies whose mothers get prenatal care.


The United States experienced a slight increase in births in 2021 over 2020. It was the first increase in seven years. Most births occurred among women age 25–34. While pregnancy generally lasts about 40 weeks, it can take six weeks or more to recover. Complications can happen, along with short- and long-term health consequences for you and your baby. That's why prenatal and follow-up care is so important to both parent and child.

Frequently Asked Questions

  • Can I trust a home pregnancy test?

    Yes. Home pregnancy tests are about 99% accurate, provided they're used correctly and the timing is right. If your test is positive, it's time to make a healthcare provider appointment. If it's negative, you can repeat it in a few days if you still don't have your period.

  • How soon can I get pregnant after having a baby?

    You can get pregnant again in as little as three weeks after the birth of a baby, even if you're breastfeeding and haven't had a period yet.

  • How do I know if I have the baby blues or postpartum depression?

    The baby blues are feelings of sadness, anger, or anxiety that occur about two to three days after childbirth. These feelings generally pass within a week or two without treatment. Postpartum depression requires treatment. It involves intense feelings of despair that interfere with your ability to function. It can occur up to a year after childbirth but typically starts after about one to three weeks.

17 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. U.S. Department of Health & Human Services. Office on Women's Health. Stages of pregnancy.

  2. Centers for Disease Control and Prevention. Births: Provisional data for 2021.

  3. March of Dimes. Your body after baby: The first 6 weeks.

  4. The American College of Obstetricians and Gynecologists. Having a baby after age 35: How aging affects fertility and pregnancy.

  5. U.S. Department of Health & Human Services. Office of Population Affairs. Trends in teen pregnancy and childbearing.

  6. Centers for Disease Control and Prevention. Multiple births.

  7. Centers for Disease Control and Prevention. What is stillbirth?

  8. March of Dimes. Miscarriage.

  9. Centers for Disease Control and Prevention. Working together to reduce black maternal mortality.

  10. March of Dimes. Premature birth report card.

  11. World Health Organization. Adolescent pregnancy.

  12. U.S. Department of Health & Human Services. Office on Women's Health. Prenatal care.

  13. Centers for Disease Control and Prevention. Maternal mortality rates in the United States, 2020.

  14. Centers for Disease Control and Prevention. Mortality in the United States, 2020.

  15. U.S. Department of Health & Human Services. Office on Women's Health. Pregnancy tests.

  16. National Health Service U.K. Sex and contraception after birth.

  17. American College of Obstetricians and Gynecologists. Postpartum depression.

By Ann Pietrangelo
Ann Pietrangelo is a freelance writer, health reporter, and author of two books about her personal health experiences.