Ultrasonic growth parameters in fetuses of mothers with primary addiction to cocaine

Neonatal drug withdrawal

Maternal use of certain drugs during pregnancy can result in transient neonatal signs consistent with withdrawal or acute toxicity or cause sustained signs consistent with a lasting drug effect. In addition, hospitalized infants who are treated with opioids or benzodiazepines to provide analgesia or sedation may be at risk for manifesting signs of withdrawal. This statement updates information about the clinical presentation of infants exposed to intrauterine drugs and the therapeutic options for treatment of withdrawal and is expanded to include evidence-based approaches to the management of the hospitalized infant who requires weaning from analgesics or sedatives.

Prenatal cocaine exposure

Cocaine abuse is a significant problem not only in the general population but also among pregnant women. Since cocaine readily crosses the placenta and is metabolized slowly in fetuses, they can be exposed to significant levels of cocaine for long periods. In humans the most common consequences of cocaine abuse during pregnancy include premature birth, lower birth weight, respiratory distress, bowel infarctions, cerebral infarctions, reduced head circumference, and increased risk of seizures. Behaviorally these newborns show an increased degree of "tremulousness," crying and irritability, and are over-reactive to environmental stimuli. Within a month these behaviors have recovered dramatically, but not to normal levels. Thus while there are a number of abnormalities associated with cocaine-exposed neonates, they are not imminently debilitating or life-threatening. However, the long-term consequences of this prenatal cocaine exposure remain to be elucidated. We have examined a rat model for neurochemical, neuroanatomical and behavioral changes resulting from prenatal cocaine exposure. Since cocaine is known to act by blocking the inactivation of the neurotransmitters dopamine, serotonin and norepinephrine, our studies have focused on brain dopamine (DA) and serotonin (5-HT) pathways. In this model system we have found neurochemical changes that are present at birth and that return to normal as the rat ages--similar to the recovery observed in infants. However, there are other neurochemical, anatomical and behavioral changes that persist after birth which may provide insights into the long-term consequences. It is hoped that by understanding the changes occurring in this rat model we will be better prepared to devise pharmacological interventions to circumvent the secondary consequences of prenatal cocaine exposure. These consequences might include increased susceptibility to drug addiction, seizures, depression, schizophrenia, Parkinson's disease, etc.

The effect of chronic cocaine exposure throughout pregnancy on maternal and infant outcomes in the rhesus monkey

To explore the effects of gestational cocaine exposure in a nonhuman primate model, pregnant rhesus monkeys were either treated (N = 10) with escalating doses of cocaine up to 7.5 mg/kg (IM), three times per day, 5 consecutive days per week, prior to conception and throughout gestation, or were not treated (N = 10) with cocaine at all. Substantial levels of both cocaine and its major metabolite, benzoylecgonine, were observed in samples of hair taken at birth from mothers and infants of the cocaine-treated group. Despite these differences in cocaine exposure, the experimental groups did not differ significantly with respect to maternal outcome, as measured by body weight again during pregnancy and length of pregnancy. On the other hand, the experimental groups did differ significantly with respect to infant outcome, as measured at birth by body weight, overall length, and crown circumference, all of which were decreased in the cocaine-treated group. A variety of reflexes tested at birth were normal in the cocaine-treated group. It was concluded that, in a rhesus monkey model, chronic cocaine exposure throughout pregnancy had no significant effect on maternal outcome, but did significantly affect infant outcome as assessed in this investigation.

The effect of chronic cocaine exposure during pregnancy on maternal and infant outcomes in the rhesus monkey

To explore the effects of gestational cocaine exposure in a nonhuman primate model, pregnant rhesus monkeys were treated from about 1 month of gestation until term with either 0 (N = 3), 0.3 (N = 3), 1.0 (N = 3), or escalating doses up to 8.5 (N = 3) mg/kg (IM), three times per day, 5 consecutive days per week. Despite these differences in cocaine exposure, the experimental groups did not differ significantly with respect to maternal outcome, as measured by body weight gain during pregnancy and length of pregnancy. A clear dose-response relationship was observed between the cumulative dose of cocaine administered during gestation and the levels of both cocaine and its major metabolite, benzoylecgonine, in samples of infant hair taken at birth. However, the experimental groups did not differ significantly with respect to infant outcome, as measured at birth by body weight, overall length, crown-to-rump length, rump-to-heel length, biparietal diameter, and crown circumference. Furthermore, the experimental groups did not differ significantly with respect to the integrity of a variety of infant reflexes tested at birth. It was concluded that, in a rhesus monkey model, chronic cocaine exposure during pregnancy had no significant effect on maternal and infant outcomes as assessed in this investigation.

Prenatal cocaine decreases the trophic factor S-100 beta and induced microcephaly: reversal by postnatal 5-HT1A receptor agonist

In utero exposure to cocaine results in neurobehavioral abnormalities in both clinical and laboratory studies. Cocaine administration from embryonic day 13 to parturition disrupts the distribution of S-100-positive astrocytes in the hippocampus and subplate region of the cortex in cocaine-exposed animals. Postnatal treatment with ipsapirone, a 5-HT1A agonist, shown to stimulate glial release of S-100, alleviated the cellular disruptions and growth retardation caused by prenatal cocaine exposure.

Neurosonographic imaging of small-for-gestational-age neonates exposed and not exposed to cocaine and cytomegalovirus

We sought to prospectively identify the role of neurosonography in the evaluation of a consecutive group of small-for-gestational-age (SGA) neonates, and also to identify the association of neurosonographic findings with cocaine exposure and cytomegalovirus (CMV) infection. Neurosonographic imaging was performed in 180 SGA neonates within 72 hours of birth. Urine samples were screened for CMV and cocaine metabolites (CM) in all cases. Sixty-five neonates (37.5%) had an abnormal neurosonographic appearance. Nine neonates were positive for CMV and 31 neonates were positive for CM. Focal echolucencies (27), ventricular dilation (27), and subependymal hemorrhages (12) were the most common neurosonographic abnormalities. The first two were more common with CM (p < .05). An abnormal neurosonographic pattern was seen more often in SGA neonates with CM (54.8%, 17 of 31; p < .05) and CMV (67%, 6 of 9; p < .01) as compared with the rest (32.6%, 44 of 135; p < .01). Among those without CM or CMV, prematurity was associated with an increased risk for abnormality (p < .001 between groups), specifically subependymal hemorrhage, ventricular dilation, and porencephalic cysts. Five CMV-positive neonates showed periventricular, echogenic foci mainly in the area of the frontal horn. Two new findings with SGA were caudate nucleus echogenicity and a "moth-eaten" appearance of the thalamus, each found in three infants. Neurosonographic imaging is useful in the evaluation of SGA neonates. Focal echolucencies and caudate echogenicity suggest maternal cocaine use, and periventricular echogenic foci strongly suggest fetal CMV infection.

Cocaine abuse during pregnancy: psychiatric considerations

Cocaine abuse is an increasing problem in the obstetric population. It not only poses a health risk to the pregnant woman, but can precipitate premature labor and abruptio placentae, and has been associated with a number of physical and behavioral problems in the newborn. Evaluation and management of the pregnant cocaine abuser is similar in most respects to that of nonpregnant adults, but diagnosis, psychotherapy, and pharmacotherapy is strongly influenced by the pregnancy. This article describes the risks of cocaine use during pregnancy and outlines the evaluation and management of the pregnant cocaine abuser.

Relationship between gestational cocaine use and pregnancy outcome: a meta-analysis

Despite a growing number of studies that have investigated the reproductive effects of maternal cocaine use, a homogeneous pattern of fetal effects has not been established and there is little consensus on the adverse effects of the drug. We used meta-analysis to evaluate the reproductive risks of cocaine. We reviewed the 45 scientific papers published in the English language dealing with effects of cocaine used during pregnancy on pregnancy outcome in humans, and identified 20 papers eligible for meta-analysis (cocaine use in pregnancy, pregnancy/fetal outcome studies, human studies, original work, cohort or case control studies, control group present, English language). Our analysis revealed that very few adverse reproductive effects could be shown to be significantly associated with cocaine use by polydrug users when compared to control groups of polydrug users not using cocaine [genitourinary malformations; odds ratio of 6.08 (95% CI 1.18-31.3); gestation age: Cohen's d 0.37 (CI 0.2-0.55)]. When the control groups consisted of no drug users, the polydrug users abusing cocaine had a higher risk for spontaneous abortions [odds ration 10.50 (CI 11.74-64.1)]. Similarly, comparison of users of cocaine alone or no drug users revealed a higher risk for in utero death, in addition to genitourinary tract malformations. Analysis of continuous variables (head circumference, gestational age, birth weight and length) revealed that the effect size was dependent upon the nature of the comparison. Comparison of cocaine users to no drug users consistently yielded a medium effect size (Cohen's d) between 0.50 and 0.58, while comparison of polydrug/cocaine users to polydrug/no cocaine users provided effect sizes small to non existent (0.06-0.37). These discrepancies suggest that a variety of adverse reproductive effects commonly quoted to be associated with maternal use of cocaine may be caused by confounding factors clustering in cocaine users.

Brain hemorrhages in cocaine-exposed human fetuses

Autopsies of 4 fetuses exposed to maternal cocaine are reported. Brain examination revealed hemorrhages in 3 of the fetuses involving the germinal matrix. The hemorrhages resembled subependymal germinal matrix hemorrhages seen as postnatal complications in premature infants with idiopathic respiratory distress syndrome. One of the placentas had sonographic evidence of abruption which could not be confirmed pathologically. The findings are discussed in light of reports of neurobehavioral deficits and other congenital anomalies in children and animals exposed to cocaine in utero. Speculations about the pathophysiologic events leading to these findings are made.

Cocaine effects on fetal development: a comparison of clinical and animal research findings

The clinical and animal literature describing the effects of cocaine use during pregnancy is reviewed. The difficulties associated with studying populations using illicit drugs during pregnancy and the multiple risk factors present in cocaine-using pregnant women limit the strength of the drug-associated effects. Nevertheless, cocaine use during pregnancy is associated with a significant number of obstetrical complications, small for gestational age infants and neurobehavioral abnormalities. In animal studies, only the neurobehavioral abnormalities could be demonstrated following the administration of non-toxic doses of cocaine. Furthermore, animal studies indicate that neurochemical changes, including those identified in the neuroendocrine axis, persist into adulthood.

Prenatal cocaine exposure in the Long-Evans rat: I. Dose-dependent effects on gestation, mortality, and postnatal maturation

Pregnant Long-Evans rats were injected daily with 40, 60, 80, or 100 mg/kg cocaine HCl (SC, 2% solution) from gestational days 7-20 (sperm positive = day 0). Daily doses were split evenly with half given between 9:00-10:00 a.m. and half between 3:00-4:00 p.m. An ad lib-fed group as well as nutritional control groups that were pair-fed to the 80 and 100 mg/kg cocaine dams were also evaluated (N = 11-18 liters/group). Cocaine had no effect on gestational length but did cause dose-dependent decreases in maternal food consumption and weight gain and increases in maternal mortality. Interestingly, cocaine-treated dams shows a significant increase in water consumption. In terms of offspring variables, there was a dose-dependent decrease in birth weight and postnatal weight gain in both the cocaine and pair-fed groups. There were also dose-dependent effects on litter size, stillbirths and postnatal mortality in the cocaine-treated groups as compared to the control groups. High dose cocaine treatment caused delays in several indices of physical maturation (pinna detachment, fur growth, ear opening, eye opening, vaginal opening) but not in others (incisor eruption, testicular descent). Physical anomalies and postnatal morbidity, while uncommon, were observed in animals prenatally exposed to the higher cocaine doses. Collectively, these data suggest that prenatal cocaine exposure can increase postnatal morbidity as well as increase pre-and postnatal mortality in animal offspring.

Prenatal cocaine exposure in the Long-Evans rat: II. Dose-dependent effects on offspring behavior

Pregnant Long-Evans rats were injected daily with 40, 60, 80 or 100 mg/kg cocaine HCl (SC, 2% solution) from gestational days 7-20 (sperm positive = day 0). Daily doses were split with half given between 9:00-10:00 a.m. and half between 3:00-4:00 p.m. An ad lib-fed group as well as nutritional control groups that were pair-fed to the 80 and 100 mg/kg cocaine dams were also evaluated (N = 11-18 litters/group). The negative geotactic reaction of the offspring, evaluated from day 2-14 (birth = day 0), showed no group differences. Spontaneous alternation behavior in a T-maze showed no evidence of perseveration in any group on either day 21 or day 80. Most cocaine-treated offspring showed an altered preference in turning right versus left on day 21. Activity monitor behavior showed that the cocaine-treated and pair-fed offspring were hypoactive on day 20. Some degree of hypoactivity was still evident on day 49, but absent on day 80. The passive avoidance behavior of day 19 offspring showed no group differences in acquisition of task learning. The 100 mg/kg cocaine offspring did show significantly poorer retention of task learning 48 hr later. On day 80, no group differences were seen in passive avoidance behavior. Acquisition of an active avoidance behavior on day 80 was significantly poorer in the 100 mg/kg cocaine group.

Development under the influence of cocaine. I. A comparison of the effects of daily cocaine treatment and resultant undernutrition on pregnancy and early growth in a large population of rats

After administering cocaine to pregnant and lactating dams in oral dosages ranging from 5 to 90 mg/kg/day, we observed a slight increase in fatalities starting at 60 mg/kg/day, followed by a sharp rise fatalities at higher dosages. Therefore, a dosage near 60 mg/kg/day by the oral route appears to mark a useful threshold between highly lethal dosages and an acceptable, sublethal dosage for chronic studies of pregnant rats. At 60 mg/kg/day, there was a marginal trend toward less weight gain in the cocaine-treated dams during pregnancy, followed by a much more pronounced lag in weight recovery following parturition. Neither prematurity nor any reduction in litter sizes and birth weights was consistently observed at dosages below 90 mg/kg/day; however, poor maternal care was evident when the dams received dosages of 80-90 mg/kg/day, producing a very high death rate in the neonatal offspring. Internal bleeding (intracranial and subcutaneous) was also observed in three neonates whose dams received cocaine at rates of 60-90 mg/kg/day, confirming a similar clinical observation and indicating a direct action of cocaine toxicity on the fetus. Although fetal growth and development were not significantly altered by administering the pregnant dams 60 mg/kg/day, there was a higher death rate in the offspring during the initial 24 hr after delivery. Weight gain appeared transiently retarded early in the suckling period, although similar growth retardation was observed in the offspring of pair-fed controls. These results indicate that the dam's undernourishment contributes much to the early growth retardation resultant from cocaine administration. The most striking effect of cocaine on the offspring, after considering undernourishment, appears to be an increased mortality in the neonatal period (60 mg/kg/day and higher), apparently resulting from poor maternal care. The greatest risk of all was the death of the dam at any point beginning with the second administration of cocaine at 60 mg/kg/day and increasing precipitously at any higher dosage.

Effects of cocaine on the human fetus: a review of clinical studies

The abuse of cocaine in this country has reached epidemic proportions and has generated great concern for the effects of the drug on the fetus when used during pregnancy. Although educational campaigns cite adverse fetal effects as a deterrent to using the drug, there are limited data on which to base a true risk assessment. This paper reviews the published studies of pregnancy outcome in cocaine-abusing mothers, with special focus on structural malformations and other neonatal risks.