Smoking and pregnancy: Understand the risks

Wonder about the risks of smoking during pregnancy? How to quit? Whether stop-smoking products are safe for the baby? Here's what you need to know about smoking and pregnancy.

By Mayo Clinic Staff

Smoking and pregnancy don't mix well — but you can take steps to boost your odds of quitting for good. Start by getting answers to the most common questions about smoking during pregnancy.

Does smoking affect fertility?

You probably know the general risks of smoking — from smelly clothes and wrinkles to heart disease and lung cancer.

If you smoke and you're planning to become pregnant, however, you have even more incentive to quit. Smoking appears to have many negative effects on fertility for both men and women, and might make it harder to become pregnant. Smoking is also linked with a greater risk of ectopic pregnancy — when the fertilized egg implants outside the uterus, usually in a fallopian tube.

How does smoking during pregnancy affect a baby?

Smoking during pregnancy exposes a baby to many harmful chemicals, including carbon monoxide. These chemicals limit the baby's supply of oxygen and the delivery of nutrients. Smoking during pregnancy has also been linked with many health problems, including:

  • Problems with the placenta
  • A reduction in birth weight
  • Preterm premature rupture of the membranes — when the amniotic sac leaks or breaks before week 37 of pregnancy
  • Premature birth
  • Certain birth defects
  • Pregnancy loss

Smoking during pregnancy can also affect a baby after he or she is born, increasing the risk of:

  • Sudden infant death syndrome (SIDS)
  • Colic
  • Asthma
  • Childhood obesity

Some research also suggests that smoking during pregnancy might affect a child's emotional development, behavior and ability to learn. Smoking during pregnancy might even impair a child's own fertility.

How does exposure to secondhand smoke affect pregnancy?

Breathing secondhand smoke during pregnancy can also affect your baby's health. Women who don't smoke but are exposed to secondhand smoke are at increased risk of pregnancy loss or having a baby who has a low birth weight or a birth defect.

Can quitting smoking during pregnancy reduce a baby's health risks?

Absolutely. If you smoke, quitting is the best way to give your baby a healthy start. If you quit in the first four months of pregnancy, you might lower your risk of having a low birth weight baby to that of a nonsmoking woman. Quitting smoking can also reduce the risk of premature birth, pregnancy loss, infant death and other complications.

Reducing the amount you smoke during pregnancy is a step in the right direction, but quitting will have the most impact on your health and your baby's health.

March 19, 2015 See more In-depth