Assessment of exposure to opiates and cocaine during pregnancy in a Mediterranean city: Preliminary results of the “Meconium Project”

Abstract

For the first time in Europe, the “Meconium Project” aimed to estimate the prevalence of drug use by pregnant women and the effects of exposure to illicit drugs during pregnancy on the fetus and infant. Between October 2002 and February 2004, 1151 (79%) dyads among the 1439 mother–infant dyads from the Hospital del Mar, Barcelona, Spain, met eligibility criteria and agreed to participate in the study. We present preliminary results on the first 830 meconium samples and 549 mother–infant dyads, for which statistical analysis of socio-economic and demographic characteristics and newborn somatometry was completed. The meconium analysis showed an overall 7.9% positivity for drugs of abuse, with 6-monoacetylmorphine and cocaine being the analytes, most frequently found in samples positive for opiates and cocaine. Structured interview disclosed 1.3, 1.8 and 1.3% of mothers exposed to opiates, cocaine and both drugs, while only one mother declared ecstasy consumption. Meconium analysis showed that prevalence of opiates, cocaine and combined drugs exposure was 8.7, 4.4 and 2.2%, respectively, and confirmed the case of ecstasy use. Arecoline, the main areca nut alkaloid, was found in meconium specimens from four Asiatic newborns, whose mothers declared beetle nut consumption during pregnancy. Parental ethnicity was not associated with drug use, nor was the social class, although a higher tendency toward drug consumption was observed in professional and partly skilled mothers. Drug consuming mothers showed a higher number of previous pregnancies and abortions (p < 0.05) when compared to non-consumer mothers (meconium negative test), probably due to a lack of family planning. Consumption of opiates and cocaine during pregnancy was associated with active tobacco smoking, a higher number of smoked cigarettes and cannabis use. Exposure status and smoking behavior correlated with significantly lower birth weight in newborns from mothers exposed only to cocaine and to opiates and cocaine simultaneously. Of the four newborns exposed to arecoline, one showed a low birth weight, low intrauterine growth, hyporeflexia and hypotonia.

Introduction

The accurate assessment of fetal exposure to drugs of abuse through the objective measurement of biomarkers could provide the basis for appropriate treatment and follow-up of newborns that present symptoms of drug withdrawal. Furthermore, information regarding the actual prevalence of illicit drug use during pregnancy could also be disclosed [1].

During the last decades, urine has been the specimen of choice for drugs of abuse screening in newborns [2]. However, drugs present in the urine reflect consumption or exposure during the preceding 1–4 days [3]. Investigators have reported the utility of meconium, the first fecal matter passed by a neonate whose formation starts between the 12th and 16th week of gestation, as a test specimen in the screening of newborns for drug abuse [4], [5], [6]. Meconium analysis extends the window of detection of drug use to approximately the last 20 weeks of gestation, and has been used to assess the prevalence of in utero drug exposure [3], [5], [7].

For the first time in Europe, the “Meconium Project” aimed to estimate the prevalence of drug use by pregnant women and the effects of chronic exposure to illicit drugs on the fetus and infant by meconium analysis, maternal structured interview and clinical observations. Mother–infant dyads were recruited in Barcelona, a European city located on the Mediterranean coast. Due to its position in Europe and in Spain, Barcelona is a centre of both industrial and cultural vitality, attracting tourists and business people, and immigrants mainly from South America, Northern Africa (Magreb) and Asia (Pakistan, India and Bangladesh). Although recent data on illicit drug consumption in women of child bearing age were not available for Barcelona itself, the 2003 Spanish National Survey on Drug Abuse [8] showed that the percentage of women 20–35 years of age who admitted drug use in the previous 12 months was 9.4, 4.6, 0.01 and 1.5% for cannabis, cocaine, heroin and 3,4 methylenedioxymethamphetamine-ecstasy-(the only amphetamine derivative that was queried), respectively. Compared to data from other European Union (EU) member states [9], Spain showed the highest percentage of cocaine consumption in the general population, with percentages of cannabis and ecstasy use among the highest in the EU (after Portugal and the United Kingdom and Ireland and United Kingdom, respectively) and that of heroin among the lowest.

To our knowledge, there are only two studies on the prevalence of drugs of abuse use during pregnancy in the European Union and both referred to the city of London [10], [11]. These studies disclosed that 10 and 15.6% of pregnant women had a positive urine test documenting illicit drug exposure. Although these data represented a more objective measure of drug consumption with respect to a self-reported questionnaire, they only provided information that reflected drug use over a narrow time-window.

This paper presents the preliminary results of the “Meconium Project”. Data on the prevalence of opiates, cocaine and amphetamines consumption based on meconium analysis were for 72% of the study population, while statistical analysis of socio-economic and demographic characteristics and newborn somatometry were completed for 48% of the study population. Furthermore, some data regarding the presence of arecoline, the principle areca nut alkaloid [12] in meconium samples of Asian newborns, whose mothers declared areca nut or betel nut consumption during the prenatal clinical interview [13], were reported together with clinical outcomes.