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Alcohol and illicit drugs are toxic to the placenta and developing fetus and can cause congenital syndromes and withdrawal symptoms.
While exposure to some toxic substances does not imply illegal actions by the mother, some do. In any case, the home situation should be evaluated to determine if the infant will be safely cared for after discharge. With the supportive help of relatives, friends, and visiting nurses, the mother may be able to care for her infant. If not, foster home care or an alternative care plan may be best.
Alcohol:
Alcohol exposure in utero can cause fetal alcohol syndrome (FAS), a variable constellation of physical and cognitive abnormalities. At birth, infants with FAS can be identified by small stature and a typical set of facial traits including microcephaly, microphthalmia, short palpebral fissures, epicanthal folds, a small or flat midface, a flat elongated philtrum, a thin upper lip, and a small chin. Abnormal palmar creases, cardiac defects, and joint contractures may also be evident. After birth, cognitive deficits become apparent. The most serious manifestation is severe mental retardation, thought to be a teratogenic effect of alcohol given the high number of retarded infants of alcoholic women; FAS may be the most common cause of noninherited mental retardation. No single physical or cognitive finding is pathognomonic; lesser degrees of alcohol use cause less severe manifestations, and the diagnosis of mild cases can be difficult because partial expression occurs. It is often difficult to distinguish the effects of alcohol on the developing fetus from those of other exposures (eg, tobacco, other drugs) and factors (eg, poor nutrition, lack of health care, violence) that affect women who drink excessively.
Diagnosis is given to infants with characteristic findings born to chronic alcoholics who drank during pregnancy.
Because it is unknown when during pregnancy alcohol is most likely to harm the fetus and whether there is a lower limit of alcohol use that is completely safe, pregnant women should be advised to avoid all alcohol intake. Siblings of an infant diagnosed with FAS should be examined for subtle manifestations of the disorder.
Barbiturates:
Prolonged maternal abuse of barbiturates may cause neonatal drug withdrawal with jitteriness, irritability, and fussiness that often do not develop until 7 to 10 days postpartum, after the neonate has been discharged home. Sedation with phenobarbital 0.75 to 1.5 mg/kg po or IM q 6 h may be required and then tapered over a few days or weeks, depending on the duration of symptoms.
Cocaine:
Cocaine inhibits reuptake of the neurotransmitters norepinephrine and epinephrine ; it crosses the placenta and causes vasoconstriction and hypertension in the fetus. Cocaine abuse 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 to neurologic damage if the infant survives. Neonates born to addicted mothers have 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; GU malformations, including prune-belly syndrome; and intestinal atresia or necrosis. All are caused by vascular disruption, presumably secondary to local ischemia from the intense vasoconstriction of fetal arteries produced 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.
Opioids:
Opioid exposure in utero can cause withdrawal on delivery. The neonate of a woman addicted to opioids should be observed for withdrawal symptoms, which usually occur within 72 h after delivery. Characteristic signs of withdrawal include irritability, jitteriness, hypertonicity, vomiting, diarrhea, sweating, seizures, and hyperventilation that produces respiratory alkalosis. Prenatal benzodiazepine exposure may cause similar effects.
Mild withdrawal symptoms are treated by a few days of swaddling and soothing care to alleviate the physical overarousal and giving frequent feedings to reduce restlessness. With patience, most problems resolve in no more than a week. Severe symptoms can be controlled by diluting tincture of opium (which contains 10 mg morphine /mL) 25-fold with water and giving 2 drops (0.1 mL)/kg po q 4 h. The dose can be increased by 0.1 mL/kg q 4 h as needed. Phenobarbital 0.75 to 1.5 mg/kg po q 6 h may also control withdrawal symptoms. Treatment is tapered and stopped over several days or weeks as symptoms subside.
The incidence of SIDS is greater in infants born to opioid addicts but still is < 10/1000 infants, so routine use of home cardiorespiratory monitors is not recommended for these infants.
Last full review/revision November 2005
Content last modified November 2005
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