More than half of pregnant women take medicines, drink alcohol, smoke, or use illicit drugs at some time during pregnancy.
Taking certain drugs and medicines while pregnant may hurt your baby or cause a miscarriage
In general, you should avoid medicines during pregnancy unless they're necessary
Talk to your doctor about which of your medicines, vitamins, and herbal supplements are necessary and which ones you shouldn’t take
Drinking alcohol during pregnancy is a major cause of birth defects
How do drugs affect pregnancy?
Many medicines and drugs taken by pregnant women are carried to the baby in the womb by crossing the placenta. The placenta is an organ on the inside of the uterus (womb) that carries blood with oxygen and nutrition to the baby. Certain medicines and drugs can:
Cause the baby's organs to grow abnormally, leading to birth defects or death
Affect the placenta so it doesn’t work properly
Cause the baby to be born too early
How do I know if a medicine is safe to take during pregnancy?
Many medicines and vaccines (shots) aren't safe for pregnant women.
On the other hand, there are some medicines and vaccines that are important to take during pregnancy. They prevent health problems that can harm you or your baby. You shouldn't just stop taking these medicines when you get pregnant. You may need to take medicine during pregnancy if you have a disease that can hurt you or your baby, such as:
Seizures (epilepsy)
Talk to your doctor about the medicines you take:
As soon as you know you're pregnant, tell your doctor
Ask your doctor about the risks and benefits of your prescription medicines so you can decide whether to continue them or stop them
Tell your doctor about any vitamins, supplements, and non-prescription (over-the-counter) medicine you take and ask about their risks
If a medicine you take is risky, doctors can often replace it with a safer medicine. And sometimes even a dangerous medicine is worth taking to treat an even more dangerous illness. For example, you may need to take a medicine called a blood thinner to prevent fatal blood clots. Your doctor will choose the right medicine to keep you and your baby healthy. Always talk with your doctor before stopping, starting, or changing your medicines.
Vaccines
During pregnancy and the first few months of life, your baby is protected against many infections from your immune system. This protection comes to your baby through your bloodstream and across the placenta during pregnancy. If you haven't had all your vaccinations, some are safe to get during pregnancy. However, some vaccines shouldn't be given and some are given only when you have a high risk of infection.
Your doctor will recommend vaccines that are safe to give during your pregnancy:
Women who are pregnant, breastfeeding, trying to get pregnant now, or might become pregnant in the future should get the COVID-19 vaccine (see also CDC: COVID-19 Vaccines While Pregnant or Breastfeeding).
Women should get a flu shot any time during pregnancy, before and during the flu season. Pregnant women should NOT get the live attenuated vaccine (LAIV or nasal spray).
Women who are between 27 and 36 weeks pregnant should get the Tdap vaccine (protects against tetanus, diphtheria and pertussis, which is whooping cough)
Vaccines that aren't safe during pregnancy include:
Rubella vaccine (the measles, mumps, and rubella [MMR] vaccine)
What problems do drugs cause during pregnancy?
Some drugs that can cause problems include:
Alcohol
Cigarettes (tobacco)
Marijuana (legal in some states)
Alcohol
Alcohol is a leading cause of birth defects. It can cause:
Fetal alcohol syndrome
Miscarriage
Low birth weight
Behavior problems in childhood
Fetal alcohol syndrome is a set of problems that includes abnormal development of the baby's head and face, brain damage, low intelligence, stunted growth, and other problems. As few as 3 alcoholic drinks a day can cause fetal alcohol syndrome.
You shouldn't drink alcohol while pregnant.
Caffeine
Doctors are unclear if caffeine during pregnancy harms a baby. Caffeine is in coffee, some teas, some sodas, energy drinks, chocolate, and some drugs.
Doctors think that caffeine is safe in small amounts, such as one cup of coffee per day.
However, drinking more than 7 cups of coffee per day may cause:
Miscarriage or stillbirth
Premature birth (a baby that is born too early)
Low birth weight
Doctors suggest drinking very little caffeine during pregnancy. You can try decaffeinated drinks instead.
Cigarettes
If you smoke cigarettes when pregnant or even breathe in smoke from people who are smoking, it can hurt your baby. It may cause:
Low birth weight
Birth defects of a baby’s heart, brain, and face
Miscarriage
Premature birth (a baby that is born too early)
Problems with a child’s growth, behavior, and intelligence
You shouldn't smoke at all while pregnant and should avoid being around smoke as much as you can.
Marijuana
Doctors are unclear if marijuana during pregnancy harms a baby but suggest that you avoid it. Marijuana may cause behavior problems in your baby if you use it heavily while pregnant.
Aspartame
Aspartame is an artificial sweetener in some food and drinks and small amounts may be safe during pregnancy. For example, pregnant women should drink less than 1 liter (about 3 cans) of diet soda per day.
However, pregnant women with a disease called phenylketonuria shouldn't eat or drink aspartame.
What problems do illicit drugs cause during pregnancy?
Injecting drugs also increases the chance of a pregnant woman giving her baby infections, such as hepatitis or HIV.
Illicit drugs that can cause problems include:
Amphetamines
Bath salts
Hallucinogens
Opioids
Amphetamines
Amphetamines during pregnancy may cause:
Birth defects, especially of the heart
Problems with a baby’s growth before birth
Bath salts
Bath salts is the name given to a group of drugs made from different chemicals that give the same high as amphetamines. Using bath salts during pregnancy may cause:
The baby not to get enough oxygen
Stillbirth (death of a baby before or during birth)
Placenta problems
Birth defects
Cocaine
Using cocaine during pregnancy can narrow blood vessels in the placenta, which can cause:
Miscarriage
Premature birth (a baby that is born too early)
Low birth weight
Women who use cocaine during pregnancy often do other things that can harm their babies, such as smoking, using other drugs, or getting poor medical care. Because of this, doctors aren't sure which problems are caused by the cocaine alone. Still, you shouldn't use cocaine at all while pregnant.
Hallucinogens
Miscarriage
Premature birth (a baby that is born too early)
Withdrawal symptoms in a baby
Opioids
Withdrawal symptoms in a baby
Miscarriage
Premature birth (a baby that is born too early)
Low birth weight
If you have a severe, painful injury (such as a broken bone or a bad burn), it's probably safe for your doctor to prescribe an opioid for several days. Otherwise, you should avoid using opioids.
