Melanie C. Dreher, R.N., Ph.D., F.A.A.N. is the dean of the College of Nursing of the University of Iowa in Iowa City.

 

Background

 

Recently, a 1,600-year-old tomb explored by scientists from the Hebrew University in Jerusalem revealed a glimpse of the early obstetrical use of cannabis. These researchers recovered tiny amounts of delta-6-tetrahydrocannabinol, a highly stable component of cannabis, in the abdominal area of a girl, about 14 years old, who apparently died in childbirth around A.D. 400 (Zias et al. 1993). Reports of the use of cannabis as a medicine appeared in an Egyptian papyrus from the sixteenth century B.C. In addition, medical texts from the nineteenth century held that cannabis increases the force of uterine contractions and reduces the pain of labor. Accounts from other cultures also have suggested the association of cannabis with pregnancy and perinatal health. Cambodian women who have just given birth, for example, are given a small glass of cannabis tea by the midwife before each meal in order to combat postpartum stiffness and to increase the milk supply of nursing mothers. Vietnamese women use cannabis tea for dysmenorrhea and to produce a feeling of well-being after childbirth.

 

In spite of this historical and cross-cultural evidence, medical research on cannabis has not focused on its potential therapeutic value in childbirth and pregnancy but rather on its possible damaging effects. Since the thalidomide tragedy, there has been widespread public concern about protecting pregnant women and their fetuses from the harmful effects of substances ingested during pregnancy. Today, the most commonly used illicit substance worldwide is cannabis. The United States Census Bureau estimates that 28 percent of Americans aged 18 to 25 use cannabis and that 10 percent of the women in that age group use it. Indeed, one of the questions pregnant women most frequently ask of obstetricians and nurse-midwives is whether or not they can continue to smoke cannabis. Yet it is one of the substances about which we know least.

 

As vulnerable populations, unborn fetuses have been legally protected from the experimental administration of drugs in research protocols. Therefore, much of the early research on the effects of prenatal cannabis exposure on pregnancy outcomes was conducted on primates and small mammals. Although there are several problems with drawing conclusions from animal studies and applying them to human populations, these very important studies have shown us that the psychoactive ingredient in cannabis, delta-9-THC, crosses the placenta. Since the blood supply of the placenta is rich, fairly large amounts of THC can be found there. Yet only relatively small amounts of the psychoactive ingredient actually cross the placental barrier to the fetus. The highest concentrations of THC that do cross the placental barrier are found in the fetal nervous system. Again, using non-human populations, researchers have also traced THC as it enters the milk of lactating animals and is transferred to the suckling offspring. There is, of course, reason to believe that the exposure of newborns to cannabis in breast milk may have effects. Since the period of greatest brain growth coincides with the nursing period, the potential for harmful substances to damage the brain suggests that the babies of mothers who smoke cannabis may be at risk.

 

More recently, medical research on cannabis has been conducted orr human mothers and their offspring. Among these studies is research linking the use of cannabis to neurological abnormalities, poor maternal weight gain, duration and progress of labor, fetal distress, major malformations, length of gestation, and lower birth weight (Day et al. 1991; Fried 1982; Fried et al. 1984; Gibson et al. 1983; Greenland et al. 1982; Hingson et al. 1982; Linn et al. 1983; Zuckerman 1989). In 1980, Fried provided the first published data regarding the effects of perinatal cannabis use on the human neonate. The subjects of the study were 291 pregnant women of whom 57 were reported marijuana users before or during pregnancy. Eleven of the users were described as heavy users (an average of five or more cannabis cigarettes per week) and eight of those remained heavy users throughout the pregnancy. No relationship was found between cannabis use and the amount of weight a mother gained during pregnancy, the length of pregnancy, the duration of labor, birth-weight, or the Apgar scores (a score assessing the physiological status of newborns). A significant increase of symptoms associated with nervous system abnormalities in the newborns was found, however, including the presence of a "cri-de-chat," a high-pitched cry indicating neurological abnormality or immaturity. Also, abnormal visual responses were found in two- or three-day-old newborns. Within one month, however, the infants of cannabis users could not be distinguished from the other infants except for the "cri-de-chat," and by the age of one year there were virtually no differences between exposed and nonexposed infants.

 

Since Fried's groundbreaking work, other studies have explored cannabis as a perinatal risk factor. The results of these studies, however, have been inconclusive and often contradictory mainly because it has been difficult to isolate the effects of cannabis from the many other variables that could influence the outcomes of pregnancy. The cannabis users in these studies generally had lower incomes and education, were more likely to represent a minority ethnic group, have less prenatal care, be multiple drug users, and have poorer health habits, nutrition, and social support than nonusers (Fried 1991; Richardson et al. 1989; Tennes et al. 1985). Greenland, for example, found cannabis users to have a greater incidence of abnormal progress of labor and a greater incidence of meconium staining— a sign of fetal distress (1982). When Greenland repeated his study, however, the results showed that when the mothers had better living standards, more education, and better prenatal care, there was no meconium staining (1983). Greenland's research demonstrates that clinical findings are extremely difficult to understand unless they are interpreted in relation to other lifestyle characteristics of the users. Even in Fried's research the dose-related effect was confounded by the association of heavy use with lower family income, lower education, and greater poly-drug use. In a subsequent study that included an additional 129 subjects, he identified characteristics of cannabis smokers that might have an adverse effect on newborn development. These included lower socioeconomic status, less formal education, less prenatal care, and a greater consumption of both alcohol and nicotine compared to the mothers not using cannabis.

 

Moreover, because of the legal and social sanctions against cannabis use, it has often been difficult to recruit subjects for these studies. Once recruited, it has been difficult to determine the validity of their reports about the amount and frequency of their use of cannabis and other illegal drugs. Hingson, for example, in a study of hundreds of women at Boston City Hospital, found a discrepancy between the verbal and biological reports of drug use (1986). The urine assays of THC revealed that more women smoked cannabis during pregnancy than were willing to admit it. The study also found that when women were told that their urine would be tested, they were more likely to increase the accuracy of their verbal reports.

 

Cross-Cultural Research—Why Jamaica?

 

Another important reason that studies of prenatal exposure have been so inconclusive is that virtually all of the research on prenatal cannabis exposure has been conducted in the United States and Canada, where cannabis is thought of almost exclusively in terms of its psychoactive properties—as a recreational drug. This perspective stands in marked contrast to societies in which cannabis has religious and medicinal functions. Research on cannabis conducted in other countries has shown us the importance of cultural factors in understanding the outcomes of cannabis use. We have learned, for example, from studies in Greece, Costa Rica, and Jamaica that concepts associated with cannabis use in this country such as the "amotivational syndrome" and the "stepping-stone hypothesis" simply do not hold up cross-culturally (Dreher 1982; Page et al. 1988; Comitas 1976).

 

One of the important contributions of anthropological research is to reexamine the assumptions and research findings of our own society by seeing whether they hold true in other societies. Jamaica was selected to study the use of cannabis during pregnancy because it is a society in which cannabis (or ganja, as it is called in Jamaica) has not been associated with the use of other illicit drugs and only minimally with the use of alcohol and tobacco. Furthermore, in Jamaica cannabis is not restricted to or thought of as just a recreational drug. Rather, it is considered an herb that has both religious and medicinal value. For members of the Rastafarian faith (a politico-religious movement in Jamaica), ganja is a sacred substance that is used in all religious and ceremonial activities. Even more pervasive in Jamaican society is the medicinal use of ganja. As part of an extensive repertoire of herbal remedies, ganja teas, tonics, and poultices have been used both prophylactically t9 maintain good health and prevent illness and therapeutically for a variety of complaints including upper respiratory infections, asthma, intestinal problems, glaucoma, gonorrhea, marasmus (wasting due to malnutrition) and infant diarrhea, endemic fevers, discomfort of teething, and skin burns and abrasions. Thus cannabis is integrated with many other dimensions of Jamaican culture, and even though it is officially illegal, it is governed by social rules that guide its use and inhibit abuse (Dreher 1982; Rubin and Comitas 1975).

 

WOMEN AND CANNABIS IN JAMAICA

 

In Jamaica, ganja smoking traditionally has been a working-class, male-dominated activity. Men have likely started smoking ganja at a younger age, more frequently, and in greater quantities than women. The female ganja smoker has been rare and even those women who cultivated and sold cannabis refrained from smoking the substance. On the other hand, ganja is not new to Jamaican women. As their male counterparts, they likely were exposed to ganja through the ingestion of teas and tonics as infants and small children. Subsequently, they may have experimented with smoking ganja in their teenage years. Finally, in their roles as homemakers and caregivers, women have had a long-standing involvement in the preparation of ganja teas and medicines for their families, a knowledge of which is shared through the generations. Typically, however, Jamaican females have been excluded from the adult male recreational and workgroup gatherings in which ganja is routinely exchanged and smoked. This exclusivity was rationalized by the ethnophysiological explanation that women "don't have the brains" for smoking and should restrict smoking to no more than occasional use and only in the company of their husbands or partners. Ganja tea, on the other hand, is acceptable because tea does not affect the brain but rather the blood, where it has health-promoting properties.

 

Men who were themselves ganja smokers and even those who claimed to appreciate women who would "take a draw" now and then nevertheless disapproved of the woman who attempted to smoke socially with her peers as men do with theirs. The few women who did smoke socially often were regarded as "brawling" and not respectable. The extent to which a young woman conforms to standards of respectability generally influences her success in acquiring and keeping a young man who is a cut above the rest—at least literate and steadily employed. Since the competition for such men is intense, the woman who ignored the injunctions on ganja smoking risked censure and gossip from both ganja smokers and nonsmokers. Moreover, she could be severely rebuked by her mate even though he might smoke regularly himself and require her to smoke with him in a presexual context.

 

Despite the social sanctions that limited ganja smoking by women, the number of women who smoke cannabis has increased dramatically. One reason for this increase has been the exponential growth of Rastafarianism, which endorses ganja as a sacred substance. As participating members of the religion, Rastafarian women not only are permitted to smoke ganja but are expected to do so in order to fulfill their religious obligations. A second reason for the increase in ganja smoking of females is the acknowledgment on the part of many women that in the fragile economy characterizing many rural Jamaican communities, the ability of men to provide routine support for a woman and her children is severely compromised. When there are no benefits for conforming to the social norms, those social rules tend to be observed less stringently.

 

Today it is no longer unusual to see Jamaican women smoking in a manner that is similar to the peer-oriented social smoking typical of their male counterparts. Furthermore, these women are not only grudgingly tolerated but have been given the commendatory title of "roots daughter." This term of praise and esteem is used to signify a woman who has "good brains," who can "smoke hard as a man," and with whom men can "reason" as they would with other men. The model "roots daughter" is not simply a ganja smoker, she is also a woman of dignity. She "must live up to a principle," "go about properly," and "keep a standard." If the "roots daughter" is involved in a stable union, her partner can expect her to be supportive and faithful. The "roots daughter" typically describes herself as independent—a "worker," a "fighter," a "woman with a plan." They compare themselves favorably to "lazy" and "helpless" women who do not smoke ganja (Dreher 1987).

In summary, while the vast majority of women continue to abide by the gender-linked prohibitions on ganja smoking, increasing numbers of Jamaican women breach social norms and smoke ganja with sufficient frequency and quantity to be considered chronic users by United States' standards. These nonconformists smoke on a daily basis, in a manner not unlike that of men, and continue to smoke during pregnancy and the breast-feeding period.

.

GANJA, PREGNANCY AND CHILDBIRTH

 

In 1980 we began to explore the use of cannabis during pregnancy in an area of rural Jamaica known for its heavy use of ganja. The research began with simply talking to women of all ages to better understand their attitudes and behavior regarding the use of ganja during pregnancy. Through formal interviews and casual conversations with hundreds of women, we found a wide range of opinions about the effects of ganja before and after birth. Approximately half of the women reported that smoking ganja during pregnancy probably had no effect—good or bad—on either mother or baby but confirmed the health-promoting properties of ganja tea for both mother and baby. Among those who had an opinion, however, were women who claimed that ganja use during pregnancy was potentially harmful for both mother and baby. They cited babies being "slow" to develop and born "viled up" with "cracked skin," "black mouths," and "mashed up brains" as reasons not to smoke ganja. These comments were reinforced by nurses, midwives, school teachers, and other human service workers who counseled women that their babies might be "retarded" and weigh less.

 

At the other extreme there were many women, some of whom were Rastafarians, who claimed that smoking or drinking ganja was good for both the mother and the baby because it relieved the nausea of pregnancy, increased their appetites, gave them strength to work hard, helped them to relax and sleep at night, and in general, relieved the "bad feelings" associated with pregnancy. In addition to these reported physiological effects, women also reported the psychologically uplifting role of ganja during pregnancy, i.e., "it helps me forget problems; it keeps you lively; when feeling down-hearted, me use it fe cheer up me spirit; it mek I feel nice, or smoking mek me feel more comfortable." Thus, while all of the women who attended prenatal clinics were told that ganja may have harmful effects on their babies, of the 70 smokers who were interviewed, only 11 discontinued smoking during their pregnancies. Of these, eight shifted to using ganja tea instead. One woman claimed to smoke only when she was pregnant.

 

GANJA AND THE NEWBORN

 

In order to explore these various opinions and experiences regarding the effects of prenatal ganja use, we recruited, with the help of local midwives, 30 pregnant women who smoked ganja cigarettes and 30 pregnant women who did not smoke ganja. With the help of local midwives, the two groups were matched according to socioeconomic status, age, the number of children the women had prior to their current pregnancy. The study was fully explained to both the ganja users and the mothers in the comparison group. None refused to participate, and all signed an informed consent allowing us to have access to their clinic and hospital records. We then interviewed each mother-to-be in her home where we collected detailed health, obstetrical, and social histories. Field workers continued to have regular contact with the women throughout the pre- and postnatal periods.

 

Conducting the study in one rural area provided an opportunity to compare users and nonusers drawn from the same population in which there is little variation in such factors as nutrition and prenatal care. Field workers resided in the communities and developed long-term, trusting relationships with the participants. This enhanced the credibility of self-reports of consumption and permitted confirmation by direct observation. Data concerning labor and delivery and the status of the neonate, complications, birth-weight, head circumference, and length of gestation, were retrieved from clinic and hospital records for each pregnancy and birth event.

 

The course of the pregnancies was similar in the two groups. All of the women had regular prenatal care beginning at least in the second trimester of their pregnancies. The use of alcohol and tobacco was minimal in both groups and did not exceed three beers or 10 to 15 tobacco cigarettes per week. The group of cannabis-using mothers were further classified as light, moderate, or heavy users depending on their frequency and amount of use. Light users were women who used cannabis tea only or smoked infrequently (less than ten cannabis cigarettes per week). Moderate users were women who smoked three or more days a week for a total of 11 to 20 cigarettes a week. Heavy users smoked daily, ranging from 21 to 70 cigarettes per week. Many moderate and heavy users also were regular cannabis tea drinkers. These classifications were based both on the mothers' reports and on direct observations by field-workers in homes and communities.

 

Each of the participants—whether smoker or nonsmoker—had been informed that ganja may be harmful to their babies, and each was warned by nurses and midwives in prenatal clinics and through government-sponsored prevention programs that their babies might be "slow" or "sickly" or "weigh less." Nevertheless, all of the smokers continued to use ganja during their pregnancies and into lactation. Supported by the folk belief that ganja has health-promoting properties and by the experience of relatives and neighbors, they used it as a vehicle for dealing with the difficult circumstances surrounding pregnancy and childbirth. Nineteen of the marijuana smokers in the sample reported that it increased their appetites throughout the prenatal period and or relieved the nausea of pregnancy. Fifteen reported using it to relieve fatigue and provide rest during pregnancy. All of the mothers considered the effects of ganja on nausea and fatigue to be good for both themselves and their babies, reporting that ganja "keeps you working," "gives you strength," makes you "feel relaxed," "sleep better," and "work harder." In addition to the physical effects of ganja, women frequently mentioned that smoking ganja made them feel less depressed about their "condition" of being pregnant again and having little or no support.

 

When it came time for them to deliver, the mothers carried a letter to the hospital indicating that they were participants in the study but did not say whether they were ganja smokers or nonsmokers. Each baby then was evaluated using the Brazelton Neonatal Assessment Scale (BNAS) (Als et al. 1977; Nugent 1981). In addition to the commonly used items on the scale that constitute "clusters" of neurobehavioral development, "supplementary" items were employed to assess aspects of the baby's behavior such as the quality of the infant's attention and how easy or difficult it is to get the infant's attention and facilitate his or her performance. We believed that these "supplementary" items would be particularly useful in differentiating infants who may be "at risk" through their cannabis exposure, and who may have difficulty in coping with the demands of the examination, from the less stressed, healthy infant.

 

The tests were administered by a Jamaican nurse who was trained in the use of the Brazelton exam and who did not know whether or not the baby had been exposed prenatally to ganja. The examinations were administered at one day, three days, and one month of life. Because of the rural setting and lack of transportation and communication, some of the women did not get to the hospital in time for delivery but took their babies to the hospital immediately afterward. Therefore, in order to keep the conditions of the evaluation as consistent as possible, only the three-day and one-month exams were considered in the analysis. The assessment of infant behavior at the end of the first month also can provide a functional assessment of the effects of the caregiving environment on newborn behavior. The Brazelton scores at the end of the first month, therefore, can be interpreted not only in terms of direct cannabis effects but also as a result of the effects of the environment on behavior.

 

The course of the pregnancies was similar in each group, and the two groups of infants were not significantly different according to physical exam data, including birth weight and length and gestational age. Since Apgar scores were not recorded by hospital nurses at standard time intervals, they were less reliable. Nevertheless, there were no significant differences in the Apgar scores between the two groups. At day three, there were no significant differences between the exposed and nonexposed babies on any of the items on the Brazelton exam. In order to examine the degree to which heavy marijuana use may have an effect on neurobehavioral outcomes, we then compared the performance of the heavily exposed and nonexposed infants on the BNAS on day three. Again, on day three there were no significant differences in performance on the items of the Brazelton scale.

 

At one month, however, when we compared the exposed and the non-exposed infants, the offspring of the ganja-using mothers were less irritable and h4 better motor responses than those of the nonusing mothers. The infants of heavy users also had higher scores on response to both sound and touch and visual stimuli. As a group, they were more alert, less irritable, and had a greater capacity to be consoled. They also had fewer startles and tremors. When we looked at the supplementary items, we found that the infants of the mothers who were heavy users had significantly better scores on all dimensions of the assessment including the quality of alertness, endurance, irritability, and the amount of persistence needed by the examiner to engage the babies.

 

In summary, although the comparison of exposed and unexposed newborns at three days of life revealed no positive or negative neurobehavioral effects of prenatal exposure, there were significant differences between the exposed and nonexposed infants at the end of the first month. In the general comparison between cannabis users and nonusers, the infants of using mothers showed better physiological stability at one month. In addition, these infants required less examiner facilitation to reach an organized state and become available for social stimulation. The results of the comparison of newborns of the mothers who were heavy users and those of the nonusing mothers were even more striking. The infants of the mothers who were heavy users were more socially responsive and were more autonomically stable at 30 days in comparison to their matched counterparts. The quality of their alertness was higher; their motor and autonomic systems were more robust; they were less irritable; they were less likely to demonstrate any imbalance of tone; they needed less examiner facilitation to become organized; they had better self-regulation; and were judged to be more rewarding for caregivers than the infants of nonusing mothers at one month of age. These findings are particularly remarkable considering that all of the heavily exposed infants were breast-fed and their mothers continued to smoke ganja routinely during the neonatal/breastfeeding period.

 

Conclusions

 

Given the consequences of exposure to substances and the public concern over protecting the unborn child, the medical establishment's conservative approach to the cannabis-smoking mother is understandable. Although cannabis is a very complex substance and has many identifiable components, it is THC, the psychoactive ingredient, that has dominated our attention in the United States and taken precedence over other functions of this plant. As such, it has generated considerable public censure, and ultimately laws were enacted to restrict or eliminate its use. It is therefore predictable that nurses, midwives, and public health officials claim that women who smoke cannabis during pregnancy selfishly place greater value on the immediate pleasures derived from recreational ganja smoking than on the health of their babies.

 

The findings from Jamaica, however, suggest that prenatal cannabis exposure is considerably more complex than we might first have thought. Loss of appetite, nausea, and fatigue compound the "bad feelings" that women in this study commonly reported. For many women, ganja was seen as an option that provided a solution to these problems, i.e., to increase their appetites, control and prevent the nausea of pregnancy, assist them to sleep, and give them the energy they needed to work. For women who are responsible for the full support of their households and who need to accomplish work while not feeling well, ganja smoking is an available and inexpensive solution to this problem. The women with several pregnancies, in particular, reported that the feelings of depression and desperation attending motherhood in their impoverished communities were alleviated by both social and private smoking. In this respect, the role of cannabis in providing both physical comfort and a more optimistic outlook may need to be reconceptualized, not as a recreational vehicle of escapism, but as a serious attempt to deal with difficult physical, emotional, and financial circumstances.

 

The use of cannabis by pregnant women and neonatal outcomes can be understood only with reference to the cultural context. Unlike the research participants in the United States and Fried's participants in Canada, who may be multiple drug users and who score higher on neuroticism and aggression and lower on agreeableness and conscientiousness, the Jamaican women who smoke ganja heavily are often regarded as "conscientious," "reasonable," and "dignified," and their administration of ganja to themselves and to their children (in the form of tea) actually is considered a sign of accountable, rather than derelict, parenting. Whether or not the effects of cannabis on Jamaican women in the prenatal period are real or only perceived, it is clear that for them it has at least symbolic value in assisting them through the difficulties of pregnancy, childbirth, and the postnatal experience. Thus, while it would be misguided to conclude from this study that smoking cannabis actually improves pregnancy outcomes, the Jamaican experience does suggest the importance of using the experience of other cultures to better understand human behavior and responses. Using the experience of another culture, however, makes it clear that the problem is considerably more complex than conventional pharmacological or medical research would suggest. It is obvious that ganja use during pregnancy is profoundly influenced by the social context in which it occurs and thus requires a carefully constructed risk analysis that allows us to examine not only the potential hazards but also the relative benefits of cannabis for both the mother and the baby.

 

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