Drug Usage and Fetal Development: Preliminary Evaluations of a Prospective Investigation

Abstract

The thalidomide tragedy in the German Federal Republic during the years 1959 to 1961 provided proof that a drug can pass the placental barrier during the period of sensitive organogenesis in human beings. The characteristic types of malformation syndromes depended on the status of embryonic differentiation at the time of the drug intake and on the dose of the drug, as well as other variables. With this knowledge of the importance of a specific environmental influence on perinatal development, a committee of the German Research Foundation initiated a prospective investigation in 1963 with the aim of elucidating the etiology of congenital malformations. Data have been collected on pregnancy from as early as possible after its initiation, and child development up to three years of age has been followed. The aim, regarding a significant statistical group, was to observe approximately 20,000 pregnancies and their outcome. To realize such a project within a reasonable number of years, it was necessary to organize a wide-spread collaborative study. Eighteen gynecological and obstetrical clinics, eighteen pediatric clinics and thirty special laboratories collaborated in this study. Up to the end of October, 1971, 13,548 pregnant women were registered during the first trimester of pregnancy and 10,245 deliveries, with 10,233 liveborn and 111 stillborn children, were documented. Of the pregnant women registered, 850 (6.3 percent) could not continue their participation in the project for various reasons, (e.g., change of residence, no further interest). One thousand and one-hundred eighty-one abortions were registered, i.e., the spontaneous abortion rate was 9.3 percent. Of these, 611 occurred within the first trimester of pregnancy.