Maternal hormone therapy and congenital heart disease

Exogenous female sex hormone exposure was studied in the mothers of 110 infants with conotruncal malformations of the heart, born in the years 1972-75. Cases were ascertained throughout the referral area of the Maryland State Intensive Care Neonatal Program. For each case, three normal controls were chosen from the birth population: Two matched on eight characteristics related to the likelihood of hormone-taking (race, maternal age, parity, fetal losses, gestational age, delivery mode, time of prenatal registration, private/service), and one also on the infant's sex and birthweight; the third control was chosen at random. In personal interviews, information was obtained on the mother's general health, family history, reproductive characteristics, pregnancy health, and environmental exposures. Identification of hormonal products was aided by a display of pills and packages. Maternal recall was examined in comparison to the responses of a group of mothers of infants with hypoplastic left heart ("disease controls"). Regression analysis on time elapsed since the infant's birth revealed no difference in recall between the mothers of cases and of controls. Multilogistic regression analysis, controlling for confounding variables and for scores constructed for reproductive, malformation, and exposure risks, showed no increase in relative risk for cases when compared with matched controls. When compared to random controls, the analysis suggested a possible increase in relative risk with increased environmental exposure scores; components of the risk score were excess smoking and alcohol intake, exposure to X-ray, drugs, paints, insecticides, and chemicals. The possible significance of this finding needs to be further investigated.