Miscarriage and Stillbirth Causes and Risk Factors

Miscarriage and, less commonly, stillbirth, can occur for several reasons. Your body may recognize that your baby has a chromosomal abnormality or a birth defect, and pregnancy will stop progressing. There may be some structural differences in the uterus or cervix that make it difficult to nourish or carry a baby to term. Or, an unlucky infection might harm the baby's health. Pregnancy loss rarely results from anything you did wrong.

Many people find it helpful to get a handle on possible pregnancy loss causes and risk factors when planning for a family or trying to conceive again. Here, we share miscarriage statistics and the latest research on how to keep your baby as safe as possible. Pregnancy loss is often unavoidable, but understanding why it can happen may provide perspective during a difficult time and support as you move forward.

Frequently Asked Questions

  • What causes a pregnancy loss?

    Often, miscarriages happen because a developing baby has chromosomal abnormalities: too many or too few chromosomes, information in cells that guide growth and development. Sometimes, structural problems with the uterus or cervix or certain infections, like listeria, cause miscarriage or stillbirth (pregnancy loss after 20 weeks gestation). Work, sex, spicy foods, morning sickness, and everyday stress do not cause pregnancy loss.

  • When is the highest risk of miscarriage?

    Most miscarriages happen during the first 12 weeks of pregnancy. Chemical pregnancies—loss within the first five weeks of gestation—are especially common. Around weeks 6 to 8, when a heartbeat is detected, miscarriage risk drops. Only 1% to 5% of miscarriages happen in the second trimester, between 13 and 19 weeks.

  • Can stress cause a miscarriage?

    Everyday stress does not cause miscarriage, according to the American College of Obstetricians and Gynecologists. High stress levels can increase blood pressure, which is linked to a higher risk of having a premature or low-birthweight baby, however. The March of Dimes suggests taking steps to reduce stress during pregnancy like prioritizing sleep, cutting back on unnecessary responsibilities, and talking to a mental health provider if you're overwhelmed.

  • Can not eating enough cause miscarriage?

    It's not likely. You may worry that skipping meals or vomiting during morning sickness will harm your baby, but people with these symptoms don't have higher rates of miscarriage. However, some research has linked shortages in certain nutrients, particularly folate and vitamin D, to a higher risk of pregnancy loss. Talk to your healthcare provider to make sure you're getting the nutrients you need to help your baby grow healthy and strong.

  • Will a pregnancy test show a missed miscarriage?

    A positive pregnancy test followed by a negative pregnancy test a week or two later can indicate you've had a miscarriage. This often happens if you test positive very early and then have a chemical pregnancy, which is a miscarriage in the first five weeks of gestation. Pregnancy tests may pick up residual hCG (human chorionic gonadotrophin), the hormone which your body produces when you conceive and stops making when you miscarry.

  • Does a faint line mean miscarriage?

    A faint line may just mean you're newly pregnant since pregnancy tests detect the hormone hCG (human chorionic gonadotropin), which your body starts producing when you conceive. Or, it can mean you're very well hydrated since hCG is more detectable in concentrated urine. Later in pregnancy, a faint line can indicate falling levels of hCG and a possible loss, since hCG rates should double quickly through the first 10 weeks.

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Page Sources
Verywell Family 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.
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