Differential Effects of Maternal Heroin and Methadone Use on Birthweight

Abstract

An analysis of birthweights of 337 neonates in relation to history of maternal narcotic usage was undertaken Mean birthweight of infants born to mothers abusing heroin during the pregnancy was 2,490 gm, an effect primarily of intrauterine growth retardation. Low mean birthweight (2,615 gm) was also seen in infants born to mothers who had abused heroin only prior to this pregnancy, and mothers who had used both heroin and methadone during the pregnancy (2,535 gm). Infants born to mothers on methadone maintenance during the pregnancy had significantly higher mean birthweights (2,961 gm), but lower than the control group (3,176 gm). A highly significant relationship was observed between maternal methadone dosage in the first trimester and birthweight, i.e., the higher the dosage, the larger the infant. Heroin causes fetal growth retardation, an effect which may persist beyond the period of addiction. Methadone may promote fetal growth in a dose-related fashion after maternal use of heroin.

Infants born to narcotic-addicted mothers.

“…Low birth weight. It has been established that infants born to heroin-addicted mothers are, on the average, small for gestational age (SGA), with approximately 50% below 2,500 grams (Fricker & Segal, 1978;Harper, Sia, & Blenman, 1973;Kandall, Album, Dreyer, Comstock, & Lowinson, 1975;Ramer, Webb, Ramer, & Mondanaro, 1973;Reddy, Harper, & Stern, 1971;Stone, Salerno, Green, & Zelson, 1971;Zelson, 1973;Zelson, 1976;Zelson, Rubio, & Wasserman, 1971). There is some speculation as to the cause of this high incidence of low birth weight.…”

“…On the other hand, with one exception (Davis & Chappel, 1973), infants born to mothers who are maintained on methadone are reported to fare better in regard to birth weight than infants born to mothers who are addicted to heroin (Blatman, 1973;Kandall et al, 1975;Zelson, JaLee, & Casalino, 1973). Although no firm correlation between birth weight and maternal dosage has been established (Newman, 1973;Zelson et al, 1971), it is possible that the longer the mother has taken methadone, the higher the birth weight of the infant (Zelson et al, 1973).…”

“…Although no firm correlation between birth weight and maternal dosage has been established (Newman, 1973;Zelson et al, 1971), it is possible that the longer the mother has taken methadone, the higher the birth weight of the infant (Zelson et al, 1973). Infants of methadone-addicted mothers, however, suffer a greater postnatal weight loss than do infants of heroin-addicted mothers (Kandall et al, 1975;Ostrea, Chavez, & Strauss, 1975;Strauss, Andresko, Stryker, Wardell, & Dunkel, 1974), which may be related to the fact that infants who are addicted to methadone show a higher incidence of withdrawal and have more severe withdrawal symptoms than do heroin-addicted infants (Rajegowda et al, 1972;Zelson, 1973).…”

“…In many studies no control group is reported (Brazelton & Robey, 1965;Davis & Shanks, 1975;Rajegowda et al, 1972;Wilson et al, 1973;Zarin-Ackerman, 1976). In the majority of the studies that do report control groups, populations are frequently poorly defined (Kandall et al, 1975;Kron et al, 1975; or are not well balanced in terms of important demographic variables. For example, the age of the mothers or their racial composition may differ between experimental and control groups (Lodge et al, 1975;Soule et al, 1974;Stimmel & Adamsons, 1976).…”

“…Such a methodological problem thus undermines the significance of reported developmental differences among narcotic-addicted and comparison infants (Lodge et al, 1975). Some studies have unbalanced designs because of large differences in the number of subjects in each group (Kandall et al, 1975;Lodge et al, 1975;Strauss et al, 1975). In contrast, some researchers have successfully balanced the experimental and control groups and have provided adequate descriptions of the populations (Householder, 1980;Ostrea et al, 1975).…”