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Social and Illicit Drugs During Pregnancy


Ravindu Gunatilake

, MD, Valley Perinatal Services;

Avinash S. Patil

, MD, University of Arizona College of Medicine

Reviewed/Revised Oct 2023

Exposure to secondhand smoke may similarly harm the fetus.

Alcohol Alcohol Toxicity and Withdrawal Alcohol (ethanol) is a central nervous system depressant. Large amounts consumed rapidly can cause respiratory depression, coma, and death. Large amounts chronically consumed damage the liver... read more is the most commonly used teratogen. Drinking alcohol during pregnancy increases risk of spontaneous abortion. Risk is probably related to amount of alcohol consumed, but no amount is known to be risk-free. Regular drinking decreases birth weight by about 1 to 1.3 kg. Binge drinking in particular, possibly as little as 45 mL of pure alcohol (equivalent to about 3 drinks) a day, can cause fetal alcohol syndrome Fetal Alcohol Syndrome Alcohol exposure in utero increases the risk of spontaneous abortion, decreases birth weight, and can cause fetal alcohol syndrome, a constellation of variable physical and cognitive abnormalities... read more . This syndrome occurs in 2.2/1000 live births; it includes fetal growth restriction, facial and cardiovascular defects, and neurologic dysfunction. It is a leading cause of intellectual disability Intellectual Disability Intellectual disability is characterized by significantly subaverage intellectual functioning (often expressed as an intelligence quotient < 70 to 75) combined with limitations of adaptive... read more and can cause neonatal death due to failure to thrive Failure to Thrive (FTT) in Children Failure to thrive in children is weight consistently below the 3rd to 5th percentile for age and sex, progressive decrease in weight to below the 3rd to 5th percentile, or a decrease in 2 major... read more .

Stimulants such as cocaine Cocaine Alcohol and illicit drugs are toxic to the placenta and developing fetus and can cause congenital syndromes and withdrawal symptoms. Prescription drugs also may have adverse effects on the fetus... read more or methamphetamine have indirect fetal risks (eg, maternal stroke or death during pregnancy). Their use probably also results in fetal vasoconstriction and hypoxia. Repeated use increases risk of the following:

Although the main metabolite of cannabis Marijuana (Cannabis) Marijuana is a euphoriant that can cause sedation or dysphoria in some users. Psychologic dependence can develop with chronic use, but very little physical dependence is clinically apparent... read more can cross the placenta, recreational use of marijuana use does not consistently appear to increase risk of congenital malformations or fetal growth restriction. Marijuana use during pregnancy has been linked to adverse pregnancy outcomes including small-for-gestational-age, preterm labor Preterm Labor Labor (contractions resulting in cervical change) that begins before 37 weeks gestation is considered preterm. Risk factors include prelabor rupture of membranes, uterine abnormalities, infection... read more , and infant neurodevelopmental and behavioral problems. A trend toward easier recreational access to and broader use of marijuana in several states may lead to an improved understanding of marijuana's effects over time.

Bath salts refers to a group of designer illicit drugs made from a variety of amphetamine-like substances; these drugs are being increasingly used during pregnancy. Although effects are poorly understood, fetal vasoconstriction and hypoxia are likely, and there is a risk of stillbirth, placental abruption, and possibly congenital malformations.

Hallucinogens may, depending on the drug, increase risk of the following:

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

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

Heroin increases the risk of having a small-for-gestational-age infant.

Whether consuming caffeine in large amounts can increase perinatal risk is unclear. Consuming caffeine in small amounts (eg, 1 cup of coffee/day) appears to pose little or no risk to the fetus, but some data, which did not account for tobacco or alcohol use, suggest that consuming large amounts (> 7 cups of coffee/day) increases risk of stillbirths, preterm deliveries, low birth weight, and spontaneous abortions. Decaffeinated beverages theoretically pose little risk to the fetus.

Use of aspartame (a dietary sugar substitute) during pregnancy is often questioned. The most common metabolite of aspartame, phenylalanine, is concentrated in the fetus by active placental transport; toxic levels may cause intellectual disability Intellectual Disability Intellectual disability is characterized by significantly subaverage intellectual functioning (often expressed as an intelligence quotient < 70 to 75) combined with limitations of adaptive... read more . However, when ingestion is within the usual range, fetal phenylalanine levels are far below toxic levels. Thus, moderate ingestion of aspartame (eg, no more than 1 liter of diet soda per day) during pregnancy appears to pose little risk of fetal toxicity. However, in pregnant women with phenylketonuria Phenylketonuria (PKU) Phenylketonuria is a disorder of amino acid metabolism that causes a clinical syndrome of intellectual disability with cognitive and behavioral abnormalities caused by elevated serum phenylalanine... read more , intake of phenylalanine and thus aspartame is prohibited.

Drugs Mentioned In This Article

Drug Name Select Trade
Dolophine, Methadose
ARYMO ER, Astramorph PF, Avinza, DepoDur, Duramorph PF, Infumorph, Kadian, MITIGO, MORPHABOND, MS Contin, MSIR, Opium Tincture, Oramorph SR, RMS, Roxanol, Roxanol-T
Belbuca, Brixadi, Buprenex, Butrans, Probuphine, Sublocade, Subutex
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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