Pharmacologic management of neonatal abstinence syndrome

Substance abuse among pregnant women has become a national health issue. As a result of the increase in maternal consumption of illicit drugs during pregnancy, many more infants are experiencing signs and symptoms of withdrawal during the immediate newborn period. In many instances, pharmacologic management is required to alleviate the signs and symptoms of withdrawal experienced by these infants. The article provides a review of the common drugs of abuse consumed by women during pregnancy, identifies the common signs and symptoms of infant withdrawal, describes the onset and duration of these symptoms, and discusses potential pharmacologic agents that can be used to treat infant withdrawal or neonatal abstinence syndrome.

Perinatal and neonatal issues of substance abuse

Substance abuse during pregnancy can be teratogenic for the fetus and can cause decreased growth parameters in the newborn infant. Short-term and long-term neurobehavioral problems have been documented also in babies born to substance-abusing mothers. The problem of substance abuse during pregnancy and its effects on the fetus is unique in medicine in that it is 100% preventable. Physicians will need to take an active role in leading society to take action in preventing substance abuse during pregnancy, and emphasis on this action should occur long before the woman becomes pregnant. Until medical schools and residency programs take responsibility for teaching the importance of preventing substance abuse and of identifying the substance-abuser, drug and alcohol use will continue to exact its tragic toll on future generations.

Substance use in pregnancy: do we care?

Two cohorts of substance-using women were compared retrospectively. From 1969 to 1979 a very high perinatal mortality rate (PMR 9.8%) was found among 92 polydrug-using women (1 twin excluded). Preterm delivery occurred in 25% of all pregnancies and in 30% of the children birth weight was below the 10th percentile. Nineteen women using heroin only had a worse fetal outcome (PMR 32%, preterm delivery in 47%, birth weight < 10th percentile in 42%). These results led to a strict surveillance system. In the period 1980-1989, 240 women (4 twins excluded) delivered after 16 weeks. Total fetal loss decreased to 2.1% and PMR to 0.4%, which was similar to results in controls. However, 22% of the women still delivered before 37 weeks and 27% delivered a child < 10th percentile. Methadone-using women were able to halve their dosage during pregnancy and 16 were detoxified. Multivariate analysis within the substance users of the second cohort showed that the neonatal abstinence syndrome, but not the (registered) amount of opiates used, was related to a lower birth weight. Not coping with prenatal care was related to a shorter pregnancy length. Multivariate analysis, including the controls, showed a significant relation of birth weight (345 g lower) with substance use. Also, head circumference was 0.8 cm smaller. Length of pregnancy however was related to smoking. This study shows that it is difficult to make substance users attend prenatal care, but also that women coping with prenatal care reduce substance intake. Opiate use might be responsible for lower birth weight, although not in a clear dose-response relationship, whereas lifestyle, as represented by not coping with prenatal care and the quantity of cigarette smoking, shortens the length of pregnancy.

The cocaine-exposed infant, Part II: Intervention and teaching

The incidence of cocaine use among women of child-bearing years is increasing at an alarming rate. Part I of this article described techniques for identifying and assessing the cocaine-exposed infant. Part II discusses techniques of intervention and treatment of these infants.

Malformations, withdrawal manifestations, and hypoglycaemia after exposure to valproate in utero

An unselected series is presented of 17 infants born to epileptic mothers and exposed to sodium valproate during pregnancy. Nine infants had minor abnormalities and of these infants five also had major malformations, described as the 'fetal valproate syndrome'. The most frequent malformation was congenital heart disease. Nine of the infants had manifestations of withdrawal, such as irritability, jitteriness, abnormalities of tone, seizures, and feeding problems. Four of these infants had an unrelated hypoglycaemia. The frequency of withdrawal symptoms was significantly related to the dose of valproate given to the mothers in the third trimester, and there was a tendency for both the frequency of the minor abnormalities and the major malformations to be related to the valproate dosage in the first trimester.

Neonatal withdrawal syndrome: associated drugs and pharmacologic management

Use of addicting drugs among women during pregnancy exposes newborns to potentially serious disorders. A group of symptoms referred to as neonatal withdrawal syndrome (NWS) may occur in infants born to mothers addicted to certain drugs because, at birth, the infants suddenly are cut off from the drug supply. Classes of drugs that cause NWS are those that produce addiction in adults, including the opioids (heroin, methadone, morphine), barbiturates, alcohol, and benzodiazepines. Many of the manifestations of NWS occur regardless of the class of drug, including irritability, hyperactivity, abnormal sleep pattern, high-pitched cry, tremor, vomiting, diarrhea, weight loss, and failure to gain weight. The fact that these symptoms are nonspecific makes it difficult to identify NWS unless it is specifically looked for. The onset, duration, and severity of the disorder differ based on such factors as the addictive drug used, time and amount of mother's last dose, and rate of elimination of the drug from the newborn. Pharmacologic intervention may be required to control severe symptoms and signs. The most common drugs used to modify withdrawal are phenobarbital, paregoric, chlorpromazine, and diazepam. Treatment is complicated by conflicting information on the effectiveness of various agents.

Methadone levels and neonatal withdrawal

The purpose of this study was to observe the effects of methadone exposure in utero, with special reference to maternal and neonatal methadone concentrations and neonatal withdrawal. Two groups of mother-infant pairs were studied. In the first group, serum methadone concentrations were determined in infants at 1, 6 and 24 h after delivery. In the second group, blood was obtained at 24, 48, 72 and 96 h after birth. There was no correlation between neonatal serum levels and the intensity of withdrawal symptoms. There was no relationship between maternal methadone dose at delivery or maternal serum levels and neonatal methadone levels. The results of this study may be complicated by the prenatal exposure of the neonates to other drugs of abuse apart from methadone.

[The newborn infant of the drug addicted mother. Clinical and therapeutic problems]

A revision of 16 newborns and their heroin-addicted mothers was carried out. The mean maternal age was 23.06 +/- 3.43 years, and mean duration of addiction was 3.07 +/- 1.43 years. The last dose of heroin was administered less than 24 hours prior to giving birth in every [corrected] case except one. Antenatal care was irregular and previous abortions were frequent. Two mothers had a history of syphilis, five had markers for anti-HIV antibodies. The mean duration of pregnancy was 37.8 +/- 2.28 weeks, and unknown in five cases. Mean birth weight was 2.715 +/- 281 g. Withdrawal symptoms were observed in 13 babies. Of these, 12 required treatment with phenobarbital and in 1 case with chlorpromazine as well. In 9 babies, hepatitis B prophylaxis was carried out and three had HIV antibodies.

Effects of transplacental exposure to cocaine and methamphetamine on the neonate

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Maternal narcotic abuse and the newborn

In 50 infants born to women who continued to take heroin during all or part of their pregnancy the drug withdrawal symptoms were mild and were noted in 21 infants (42%). Only nine infants required treatment. Sudden infant death syndrome occurred in two infants at 4 and 6 months.