Tobacco, alcohol and drugs can have harmful effects on anyone's health. When a pregnant or nursing woman uses these substances, her baby also is exposed to them, for all substances cross the placenta through the umbilical cord and enter into the baby's bloodstream.
While pregnant, it is best to eat well, stay healthy and avoid ingesting anything that might be harmful to the mother's or baby's health. A health care provider can give you more information about these issues.
A pregnant woman who uses drugs like cocaine, crack, heroin and methadone may have a baby born addicted to the substances she took during her pregnancy. Cocaine is one of the most harmful drugs to unborn babies. Cocaine can cause a woman to miscarry and may cause preterm birth, bleeding, fetal death and fetal strokes, which can lead to brain damage and death. After birth, a baby who has been exposed to cocaine prenatally goes through withdrawal, signs of which include jitters and irritability. These babies are hard to comfort and are often unable to respond to their mothers. Cocaine use during pregnancy also may be linked to an increased risk of sudden infant death syndrome, or SIDS.
Amphetamines or "speed" also are harmful to unborn babies. One study showed that the fetuses of mothers who used speed during pregnancy had decreased weight, length and head size. Another study showed that these babies had more strokes, or bleeding into their brains.
Marijuana can affect fetal and infant development and may cause miscarriage. Although the effects of marijuana on an unborn baby are still unknown, studies have indicated that prenatal marijuana use is linked to premature births, small birth size, difficult or long labor and an increase in newborn jitteriness.
Marijuana smoked by a pregnant woman remains in the baby's fat cells for seven to 30 days. Smoking marijuana can affect the amount of oxygen and nutrients the baby receives, which may affect growth. Marijuana is never safe during pregnancy and it can harm the baby at any stage. In addition, marijuana can have long-term effects on infants and children, such as having trouble paying attention or learning to read.
Drinking alcohol can increase the risk of miscarriage, stillbirth, newborn death and fetal alcohol syndrome (FAS). Babies with FAS have low birth weight, heart defects, facial defects, learning problems and mental retardation. Since it is not known if there is a safe level of alcohol during pregnancy, the best advice is not to drink at all. Even one drink a day has been shown to have effects on the growing fetus. The best time to stop drinking alcohol is before you conceive. If your pregnancy is unplanned, you should stop drinking as soon as you suspect you are pregnant.
Women who smoke during pregnancy are more likely to have babies who are too small. Smoking also increases the risk of miscarriage, preterm labor, stillbirth and newborn death. Babies born weighing less than 5 pounds may have more health problems early in life and learning problems later in school. If you smoke, quit now. Ask your health care provider for information about classes or support groups for pregnant women who want to quit smoking.
Some prescribed medications may be harmful to your unborn or nursing baby. If you are taking any prescribed drugs, tell your health care provider as soon as possible so that your medications can be changed or adjusted as needed.
Over-the-Counter Medicines and Vitamins
Avoid over-the-counter medicines such as antacids, laxatives, sleeping pills, cold medications and pain relievers. While some are safe for pregnant women, many are not. If you feel you need any of these medications, first check with your health care provider. This applies to large doses of over-the-counter vitamin preparations as well, for taking large doses of extra vitamins can be harmful to you and your baby.
Caffeine is present in coffee, tea, cola drinks and some medications. For at least 10 years, there has been controversy over whether caffeine is harmful during pregnancy. Some studies suggest caffeine is harmful, pointing to an increased risk of miscarriage, early delivery or lower birth weight. Other studies have shown that women who consume a moderate amount of caffeine do not experience these problems. Because results are conflicting, no one knows the true risk. We recommend drinking as little caffeine as possible.
Ask your health care provider for more information about substances and their effects on pregnancy. Remember -- your baby needs a healthy mom!
UCSF Health medical specialists have reviewed this information. It is for educational purposes only and is not intended to replace the advice of your doctor or other health care provider. We encourage you to discuss any questions or concerns you may have with your provider.
Anemia and Pregnancy
During the last half of pregnancy, your body makes more red blood cells which can cause Anemia. Learn more about causes and prevention here.
Coping With Common Discomforts of Pregnancy
Pregnancy produces many physical changes. Aside from weight and body shape, other alterations in your body chemistry and function take place. Learn more.
Diabetes in Pregnancy
Gestational diabetes refers to diabetes that is diagnosed during pregnancy. Gestational diabetes occurs in about 7 percent of all pregnancies. Learn more.
Domestic Violence and Pregnancy
Domestic violence is the most common health problem among women during pregnancy. It greatly threatens both the mother's and baby's health. Learn more here.
Eating Right Before and During Pregnancy
It is important to get the nutrients you need both before getting pregnant and during your pregnancy. Find more nutrition information including macros here.
Exercise During Pregnancy
Most women can, and should, engage in moderate exercise during pregnancy. Exercise can help you stay in shape and prepare your body for labor and delivery
FAQ: Prenatal Tests
Commonly asked questions regarding Prenatal Tests including, types available, positive screenings, diagnostic testing, health insurance coverage, and more.
HIV and Pregnancy
If you are pregnant, we recommend you be tested for the human immunodeficiency virus (HIV) even if you do not think you are at risk. Learn more here.
Sex During Pregnancy
The pregnancy may alter how a woman and her partner feel about making love, and differences in sexual need may arise. Learn more here.
The Circumcision Decision
If you give birth to a boy, you will be asked if you'd like him circumcised. This is a matter to be considered carefully before the baby is born. Learn more.
Obstetrics & Gynecology at Mission Bay – Owens Street
1500 Owens St., Suite 380
San Francisco, CA 94158
Obstetrics & Gynecology at Mount Zion
2356 Sutter St.
San Francisco, CA 94143
Obstetrics, Gynecology & Perinatal Specialties at Mission Bay – Fourth Street
Ron Conway Family Gateway Medical Building
1825 Fourth St., Third Floor
San Francisco, CA 94158
Great Expectations Pregnancy Classes
Get ready for the baby! Choose from a variety of classes that prepare moms and partners for pregnancy, birth, baby care, breastfeeding and parenting.
Lactation Consultant Support
Get support for all your breastfeeding needs. Troubleshoot with a lactation consultant, find equipment and supplies, join a support group and more.
Women's Health Resource Center
Access a range of UCSF women's health resources, such as classes, support groups, a lending library and services focused on pregnancy, birth and breastfeeding.