Prenatal Drug Exposure

ByKevin C. Dysart, MD, Nemours/Alfred I. duPont Hospital for Children
Reviewed/Revised Dec 2024
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Alcohol and illicit drugs are toxic to the placenta and developing fetus and can cause congenital syndromes and withdrawal symptoms. Prescription medications also may have adverse effects on the fetus (see table Safety of Selected Drugs in Pregnancy). Fetal alcohol syndrome and the effects of social and illicit drugs on the fetus are discussed elsewhere.

A fetus that has been exposed to illicit drugs in utero can become dependent on the drug during gestation. Therefore, the home situation should be evaluated to determine whether the infant is able to be safely cared for after discharge. Understanding local jurisdictions and laws is important because many countries and localities have mandatory reporting guidelines. With the supportive help of relatives, friends, and visiting nurses, the parent may be able to care for the infant. If not, foster home care or an alternative care plan may be best.

Amphetamines

Prenatal exposure to amphetamines has lasting subtle effects on neonatal brain structure and function. Some studies have shown decreased volume of the caudate, putamen, and globus pallidus (anatomic components of brain) in methamphetamine-exposed children, whereas other studies have not uniformly confirmed these findings (1).

Other studies indicate that prenatal methamphetamine exposure may be associated with abnormal neurobehavioral patterns or fetal growth restriction, but these findings are not yet fully established.

Barbiturates

Prolonged maternal use of barbiturates may cause neonatal drug withdrawal with jitteriness, irritability, and fussiness. These symptoms often do not develop until 7 to 10 days postpartum, after the neonate has been discharged home.

Cocaine

Cocaine inhibits reuptake of the neurotransmitters norepinephrine and epinephrine; it crosses the placenta and causes vasoconstriction and hypertension in the fetus. Cocaine use in pregnancy is associated with a higher rate of placental abruption and spontaneous abortion, perhaps caused by reduced maternal blood flow to the placental vascular bed; abruption may also lead to intrauterine fetal death or neurologic damage if the infant survives.

A neonate born to a mother with substance use disorder has low birth weight, reduced body length and head circumference, and lower Apgar scores. Cerebral infarcts may occur, and rare anomalies associated with prenatal cocaine use include limb amputations, genitourinary malformations, including prune-belly syndrome, and intestinal atresia or necrosis. All are caused by vascular disruption, presumably secondary to local ischemia caused by the intense vasoconstriction of fetal arteries caused by cocaine. In addition, a pattern of mild neurobehavioral effects has also been observed, including decreases in attention and alertness, lower IQ, and impaired gross and fine motor skills.

Some neonates may show withdrawal symptoms if the mother used cocaine shortly before delivery, but symptoms are less common and less severe than for opioid withdrawal, and signs and treatment are the same.

Marijuana

Marijuana does not consistently increase risk of congenital malformations, fetal growth restriction, or postnatal neurobehavioral abnormalities. However, women who use marijuana during pregnancy often also use alcohol, cigarettes, e-cigarettes (vapes), or a combination, which can cause fetal problems.

Opioids

Opioid exposure in utero can cause withdrawal after delivery. The neonate of a woman who used opioids chronically during pregnancy should be observed for withdrawal symptoms (narcotic abstinence syndrome [NAS]). NAS usually occurs within 72 hours after delivery, although many neonatal units observe infants for 4 or 5 days to be sure there are no significant signs of NAS.

Characteristic signs of NAS include

  • Irritability

  • Jitteriness

  • Hypertonicity

  • Vomiting and/or diarrhea

  • Sweating

  • Seizures

  • Hyperventilation that causes respiratory alkalosis

Prenatal benzodiazepine exposure may cause similar signs.

There are many scoring systems to help quantify the severity of NAS (see The Opioid Exposed Newborn: Assessment and Pharmacologic Management). Mild NAS symptoms are treated by a few days of swaddling and soothing care to alleviate the physical overarousal and by giving frequent feedings to reduce restlessness. With patience, some problems resolve in about a week.

The Eat, Sleep, Console (ESC) approach for NAS assessment (2, 3

4).

clonidine should not be given to preterm infants because of the risk of bradycardia. If clonidine is used, blood pressure should be monitored as the clonidine dose is tapered because there can be rebound hypertension.

The incidence of SUID/SIDS is greater among infants born to women with an opioid use disorder but is still low, so routine use of home cardiorespiratory monitors is not recommended for these infants.

References

  1. 1. Sanjari Moghaddam H, Mobarak Abadi M, Dolatshahi M, et alACS Chem Neurosci. 2021;12(15):2729-2748. doi:10.1021/acschemneuro.1c00213

  2. 2. Grisham LM, Stephen MM, Coykendall MR, et al: Eat, sleep, console approach: A family-centered model for the treatment of neonatal abstinence syndrome. Adv Neonatal Care 19(2):138–144, 2019. doi: 10.1097/ANC.0000000000000581

  3. 3. Dodds D, Koch K, Buitrago-Mogollon T, Horstmann S: Successful implementation of the eat sleep console model of care for infants with NAS in a community hospital. Hosp Pediatr 9(8):632–638, 2019. doi: 10.1542/hpeds.2019-0086

  4. 4. Hudak ML, Tan RC, The Committee on Drugs, The Committee on Fetus and Newborn: Neonatal drug withdrawal. Pediatrics 129:E540–E560, 2012. doi: 10.1542/peds.2011-3212

More Information

The following English-language resource may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

  1. The Opioid Exposed Newborn: Assessment and Pharmacologic Management: Scoring systems to help quantify the severity of withdrawal

Drugs Mentioned In This Article

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