Cocaine abuse: implications for pregnancy

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Inf J Gynecol Obstet, 1991, 36: 164-166 International

Federation

of Gynecology

and Obstetrics

Cocaine abuse: implications

for pregnancy

ACOG Committee Opinion: Committee on Obstetrics: Maternal and Fetal Medicine Number 8 1 - March- 1990 Cocaine has become a major public health concern due to the dramatic increase in its use over the last decade. In the 197Os,cocaine use was primarily limited to the well-to-do because of its expense, with the intranasal route preferred. More recent!y, there has been a decrease in the street tost and an increasing prevalente of intravenous and smoked routes of administration. This change in the pattem of use has increased the potential for medical complications and for compulsive or addictive use (1). Cocaine, with street names of “coke,” “snow,” “lady,” and “gold dust,” is a local anesthetic derived from the leaves of Eryfhroxylon coca, a tree indigenous to Peru and Bolivia. When administered systemically, cocaine blocks the presynaptic reuptake of sympathomimetic transmitters (norepinephrine and dopamine), allowing for excess transmitter at the postsynaptic receptor sites. The potentiation of norepinephrine results in intense vasoconstriction, an acute rise in arterial pressure, and tachycardia (2). Both the euphoria and the reinforcing or addictive effects of the drug are thought to be related to the potentiation of dopamine in the centra1 nervous system (3). Cocaine is commonly used intranasally (“snorting”), intravenously, orally, and by smoking the free alkaloid form (“freebasing”). “Crack” is a highly purified form of the free alkaloid, so named because of the cracking or popping sound made when the crystals are heated in a test tube. The drug is degraded by plasma and hepatic cholinesterases to water-soluble metabolites (benzoylecgonine and ecgonine methyl ester) (2). The most commonly employed urine test detects benzoylecgonine at a sensitivity of 300 ng/ml. The elimination halftime is approximately 4.5 hours, allowing detection in urine for 24-48 hours after varying intravenous doses (4). Int J Gynecol Obstet 36

The pharmacokinetics of cocaine use in pregnancy are poorly studied, although cocaine is known to cross the placenta readily (5). It is thought that urine tests in neonates exposed to transplacental cocaine may be positive for a similar period of time as in the adult, although benzoylecgonine has been detected in neonatal urine for up to 4 days with an assay sensitive to 10 ng/ml(6). Serious medical complications reported in association with cocaine use include the following (7): Acute myocardial infarction, both with and without underlying coronary artery disease Cardiac arrhythmias, including life-threatening ventricular arrhythmias Rupture of the ascending aorta Cerebrovascular accidents Seizures Bowel ischemia Hyperthermia Sudden death These complications are directly or indirectly attributable to the intense sympathomimetic effects of cocaine. Cocaine abuse during pregnancy should be considered a major perinatal risk factor, and it ‘may suggest multidrug use. Research in perinatal cocaine abuse is problematic because of a population of patients who tend to have unplanned pregnancies of uncertain gestational age, to seek prenatal care late, to have suboptimal nutrition, to be heavy cigarette smokers and multiple drug abusers, and to fail to keep appointments. For these reasons, data are often incomplete and control groups difficult to construct. However, studies have consistently indicated a risk of up to 25% for preterm birth

ACOG

@-11) and of up to 20% for small-for-gestational-age infants 03-10) in cocaine users. Most important, the outcomes of pregnancies complicated by cocaine abuse have consistently been shown to be worse than those complicated by abuse of other substances 02,131. Although an early report suggested a strong association between cocaine use and abruptio placentae (14), subsequent studies have indicated only a modest increase in this risk (8,9,15). Neurobehavioral abnormalities, especially the tendency for irritability and a low threshold for overstimulation, have been documented in neonates exposed to cocaine in utero (16). A greater-thanexpected frequency of certain anomalies has been suggested in cocaine-exposed neonates, including intestinal atresias and genitourinary anomalies (16-18). Other complications have been described, including a well-documented case of perinatal cerebral infarction in a neonate bom to a woman who used cocaine shortly before birth (6). The mechanism of cocaine-induced perinatal morbidity is unknown but is presumed to be related to either vasoconstriction of the placenta1 bed or a direct fetal effect from cocaine. This is supported by animal studies demonstrating dose-dependent decreases in uterine blood flow (19) and marked fetal hypoxemia, hypertension, and tachycardia (20) in pregnant ewes given intravenous cocaine. Fetal hypertension and tachycardia, but not hypoxemia, were observed with direct administration of cocaine to the fetus (20). Hypoxemia was therefore presumed to be secondary to decreased uterine blood flow. Hypotheses to explain the apparent increase in congenital anomalies include cocaine-mediated vasoconstriction leading to infarction, which may explain a defect such as intestinal atresia, and to interrupted blood flow, which may disrupt morphogenesis (17). A survey of urban hospitals (21) demonstrated positive urine toxicology for cocaine metabolites in KJ-25% of pregnancies. The seriousness. of perinatal cocaine abuse is underscored by the marked increase in use of the drug by women of childbearing age, by the misconception that cocaine is neither dangerous nor addictive, and by the ability of many cocaine users to hide their habits. Accordingly, the following recommendations are made: 1. Al1 pregnant

women should be queried

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Opinion

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regarding past and present drug use at the time of the first prenatal visit. 2. A woman acknowledging cocaine use should be carefully counseled regarding the perinatal implications of cocaine use in pregnancy and offered support mechanisms to aid in her abstinente, if appropriate. 3. In order to reinforce and entourage continual abstinente, periodic urine testing fes metabolites of cocaine may be desirable in a pregnant woman admitting to cocaine use prior to or during pregnancy. The requirement for consent may vary from state to state. 4. Urine testing in the mother or the neonate or both may be useful in some clinical situations, such as in the presence of unexplained fetal growth retardation, unexpected prematurity, or abruptio placentae in a woman not known to have hypertensive disease, even when cocaine abuse has not been previously suspected.

REFERENCES 1. Atkíns WT. Cocaine: the drug of choice. In: Chasnoff IJ, ed. Drugs, alcohoï, pregnancy and parenting. Boston: Kluwer Academie Publishen, 1988;91-96 2. Ritchie JM, Greene NM. Local anesthetics. In: Gilman AG, Goodman LS, Ral1TW, Murad F, eds. Goodman and Gilman’s the pharmacologfcal basis of therapeutics. 7th ed. New York: Macmillan. 1985;302-321 3. Jaffe JH. Drug addiction and drug abuse. In: Gilman AG, Goodman LS, Ral1TW, Murad F, eds. Goodman and Gilman’s the pharmacologlcal basis of therapeutics. 7th ed. New York: Macmillan, 1985;532-539 4. Ambre J, Ruo TI, Nelson J, Belknap S. Urinary excretion of cocaine, benzoylecgonlne, and ecgonine methyl ester in humans. J Anal Toxicol 1988;12:301-306 5. Perinatal toxicity of cocaine. Med Lett Drugs Ther 1988;30(767):59-60 6. Chasnoff IJ, Bussey ME, Savich R, Stad< CM. Perinatal cerebral infarction and matemal cocalne use. J Pediatr 1986;108(3):456-459 7. Cregler LL, Mark H. Medical compllcations of cocaine abuse. N Eng1 J Med 1986;315(23): 1495-1500 8. Cherukuri R, Minkoff H, Feldman J, Parekh A, Int J Gynecol Obstet 36

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Glass L. A cohort study of alkaloidal cocaine (“crack”) in pregnancy. Obstet Gynec011988; 72(2):147-151 9. MacGregor SN, Keith LG, Chasnoff IJ, Rosner MA, Chisum GM, Shaw P, et al. Cocaine use during pregnancy: adverse perinatal outcome. Am J Obstet Gynecol1987;157(3):686-690 10. Chasnoff IJ. Cocaine: effects on pregnancy and the neonate. In: Chasnoff IJ, ed. Drugs, alcohol, pregnancy and parenting. Boston: Kluwer Academic Publishers, 1988;97-103 11. Chouteau M, Namerow PB, Leppert P. The effect of cocaine abuse on birthweight and gestational age. Obstet Gynecol1988;72(3 ptl):351-354 12. Keith LG, MatGregor SN, Friedell S, Rosner M, Chasnoff IJ, Sciarra JJ. Substance abuse in pregnant women: recent experience at the perinatal center for chemical dependence of Northwestem Memorial Hospital. Obstet Gynecol1989;73(5 ptl):715-720 13. Chasnoff IJ, Bums KA, Bums WJ. Cocaine use in pregnancy: perinatal morbidity and mortality. Neurototicol Teratol 1987;9(4):291-293 14. Acker D, Sachs BP, Tracey KJ. Abruptio placentae associated with cocaine use. Am J Obstet Gynecol 1983;1%(2):220-221

15. Bingo1N, Fuchs M, Diaz S, Stone RK, Gromisch DS. Teratogenicity of cocaine in humans. J Pediatr 1987;110(1):93-96 16. Griffith DR. The effects of perinatal cocaine exposure on infant neurobehaviour and early matemal-infant interactions. In: Chasnoff IJ, ed. Drugs, alcohol, pregnancy and parentlng. Boston: Kluwer Academie Publishers, 1988;10!&113 17. Chasnoff IJ, Chisum GM, Kaplan WE. Maternal cocaine use and genitourinary tract malformations. Teratology 1988;37(3):201-204 18. Urogenital anomalies in the offspring of women using cocaiñe during early pregnancy-Atlanta, 1%8-1980. MMWR 1989;38(31):536-542 19. Woods JR Jr, Plessinger MS, Clarke KE. Effect of cocaine on uterine bloed flow and fetal oxygenation. JAMA 1987;257(7):957-961 20. Moore TR, Sorg J, Miller L, Key TC, Resnik R. Hemodynamic effects of intravenous cocaine on the pregnant ewe and fetus. Am J Obstet Gynecol 1986;155(4N83-888 21. Chasnoff IJ. Drug use and women: establishing a standard of care. Ann NY Acad Sci 1989;562: 208-210

Copyright 0 March 1990 This document reflects emerging clinical and scientific advances as of the date issued and is subject to change. The information should not be construed as dictating an exclusive course of treatment or procedure to be followed. The American College of Obstetricians and Gynecologists 409 12th Street, SW ??Washington, DC 20024-2188 Int J Gynecol Obstet 36