Substance Use During Pregnancy

Caffeine, which is contained in coffee, tea, some sodas, or other beverages, chocolate, and some medications, is a stimulant that readily crosses the placenta to the fetus.

It is unclear whether consuming caffeine during pregnancy harms the fetus. Research seems to suggest that consuming caffeine in small amounts (for example, one cup of coffee a day) during pregnancy poses little or no risk to the fetus.

Some research suggests that drinking more than 7 cups of coffee a day may increase the risk of having a stillbirth Stillbirth Stillbirth is death of a fetus after 20 weeks of pregnancy. Stillbirth may result from a problem in the woman, placenta, or fetus. Doctors do blood tests to try to identify the cause of a stillbirth... read more , preterm birth Preterm (Premature) Newborns A preterm newborn is a baby delivered before 37 weeks of gestation. Depending on when they are born, preterm newborns have underdeveloped organs, which may not be ready to function outside of... read more , low-birth-weight baby Small-for-Gestational-Age (SGA) Newborns A newborn who weighs less than 90% of newborns of the same gestational age at birth (below the 10th percentile) is considered small for gestational age. Newborns may be small because their parents... read more , or miscarriage Miscarriage A miscarriage is the loss of a fetus before 20 weeks of pregnancy. Miscarriages may occur because of a problem in the fetus (such as a genetic disorder or birth defect) or in the woman (such... read more .

Some experts recommend limiting coffee consumption and drinking decaffeinated beverages when possible.

Aspartame, an artificial sweetener, appears to be safe during pregnancy when it is consumed in small amounts, such as in amounts used in normal portions of artificially sweetened foods and beverages.

Anyone (including pregnant women) with phenylketonuria Phenylketonuria (PKU) Phenylketonuria is a disorder of amino acid metabolism that occurs in infants born without the ability to normally break down an amino acid called phenylalanine. Phenylalanine, which is toxic... read more , an unusual disorder of amino acid metabolism, should not consume any aspartame.

Cigarette smoking Smoking and Other Tobacco Use Tobacco use is a major individual and public health problem. Using tobacco is harmful to almost every organ in the body. Tobacco is used because of the effects of nicotine. Nicotine is highly... read more poses risks to pregnant women and fetuses. Women who are trying to get pregnant or are pregnant should try to quit smoking. Health care professionals can provide resources about smoking cessation programs.

The most consistent effect of smoking on the fetus during pregnancy is

The more a woman smokes during pregnancy, the less the baby is likely to weigh.

Birth defects of the heart, brain, and face are more common among babies of women who smoke cigarettes.

Also, the risk of the following may be increased:

In addition, children of women who smoke have slight but measurable deficiencies in physical growth and in intellectual and behavioral development. These effects are thought to be caused by carbon monoxide and nicotine. Carbon monoxide may reduce the oxygen supply to the body's tissues. Nicotine stimulates the release of hormones that constrict the vessels supplying blood to the uterus and placenta, so that less oxygen and fewer nutrients reach the fetus.

Because of the possible harmful effects of smoking during pregnancy, pregnant women should make every effort to not smoke during pregnancy, including discussing strategies with their doctor.

Pregnant women should avoid exposure to secondhand smoke because it may harm the fetus.

Drinking alcohol Alcohol Use Alcohol (ethanol) is a depressant (it slows down brain and nervous system functioning). Consuming large amounts rapidly or regularly can cause health problems, including organ damage, coma,... read more during pregnancy is the leading known cause of birth defects. Because the amount or pattern of drinking alcohol required to cause fetal alcohol syndrome is unknown, pregnant women are advised to abstain from drinking any alcohol.

The risk of miscarriage Miscarriage A miscarriage is the loss of a fetus before 20 weeks of pregnancy. Miscarriages may occur because of a problem in the fetus (such as a genetic disorder or birth defect) or in the woman (such... read more almost doubles for women who drink alcohol in any form during pregnancy, especially if they drink heavily. Risk is probably related to amount of alcohol consumed, but no amount is known to be risk-free.

Fetal alcohol syndrome is one of the most serious consequences of drinking during pregnancy. Binge drinking as few as 3 drinks a day can cause this syndrome. It occurs in about 2 of 1,000 live births. This syndrome includes the following:

Use of amphetamines Amphetamines Amphetamines are stimulant drugs that are used to treat certain medical conditions but are also subject to abuse. Amphetamines increase alertness, enhance physical performance, and produce euphoria... read more during pregnancy may result in birth defects, especially of the heart, and possibly inadequate growth before birth.

Bath salts refers to a group of synthetic drugs made from various substances that resemble amphetamine. These drugs are being increasingly used during pregnancy.

The drugs may cause the blood vessels in the fetus to narrow, reducing the amount oxygen the fetus gets.

Also, these drugs increase the risk of the following:

Cocaine Cocaine Certain substances, including caffeine, aspartame, alcohol, and tobacco, may have harmful effects on pregnant women and fetuses. Illicit drugs include amphetamines, bath salts, cocaine, hallucinogens... read more taken during pregnancy may cause the blood vessels that carry blood to the uterus and placenta to narrow (constrict). Then, less oxygen and fewer nutrients reach the fetus.

If pregnant women use cocaine regularly, risk of the following is increased:

However, whether cocaine is the cause of those problems is unclear. For example, the cause may be other risk factors that are common in women who use cocaine. Such factors include cigarette smoking, use of other illicit drugs, deficient prenatal care, and poverty.

Hallucinogens Hallucinogens Hallucinogens are a class of drugs that cause profound distortions in people's perceptions. Hallucinogens distort and intensify sensations, but the actual effects are variable and unpredictable... read more may, depending on the drug, increase the risk of the following:

Hallucinogens include methylenedioxymethamphetamine (MDMA, or Ecstasy), rohypnol, ketamine, methamphetamine, and LSD (lysergic acid diethylamide).

The main component of marijuana Marijuana Marijuana (cannabis) is a drug made from the plants Cannabis sativa and Cannabis indica that contain a psychoactive chemical called delta-9-tetrahydrocannabinol (THC). Marijuana... read more (cannabis), tetrahydrocannabinol, can cross the placenta and thus may affect the fetus. No amount of marijuana is considered safe in pregnancy though birth defects are not increased in studies. However, recent studies have suggested that marijuana use in pregnancy may be linked to low birth weight and childhood concerns including attention, learning, and behavioral problems, and changes in brain development and function.

Opioids Opioids Opioids, a class of drugs derived from the opium poppy (including synthetic variations), are pain relievers with a high potential for misuse. Opioids are used to relieve pain, but they also... read more are used to relieve pain, but they also cause an exaggerated sense of well-being, and if used too much, they can cause dependence and addiction.

Opioids, such as heroin, methadone, and morphine, readily cross the placenta. Consequently, the fetus may become addicted to them and may have withdrawal symptoms Withdrawal symptoms Opioids, a class of drugs derived from the opium poppy (including synthetic variations), are pain relievers with a high potential for misuse. Opioids are used to relieve pain, but they also... read more 6 hours to 8 days after birth. However, use of opioids rarely results in birth defects.

Use of opioids during pregnancy increases the risk of complications during pregnancy, such as

Babies of heroin users are more likely to be born small.