STUDY OF DEVELOPMENTAL ABNORMALITIES AND DEATHS AFTER HUMAN ZYGOTE EXPOSURE

Experimental studies indicated that the mouse zygote is susceptible to experimental induction of developmental anomalies including defects ( mainly hydrops), growth retardation and mid- and late-gestational deat h with certain mutagenic agents. The material of the Hungarian Optimal Family Planning Program is appropriate to check this finding in a hum an material because participants were asked to visit the coworkers of the Program immediately after the first missed menstrual period and da ta concerning potentially hazardous environmental factors were obtaine d. At that time participants were immediately after the pre-and implan tation period and they had no knowledge about their pregnancy outcomes . In 1994 the data of their pregnancy outcomes are available. Of 5453 evaluated pregnancies, 1167 were selected for this study because they visited the coworkers of the Program within 28 days post conception. O f 1167 pregnancies, 316 (27%) were exposed to some environmental facto rs, mainly drugs. A mild intrauterine growth retardation was found in the exposed group. The rate of congenital abnormalities and infant dea th did not differ between the exposed and unexposed groups. The detail ed analysis of different congenital abnormality groups also did not sh ow any significant difference between the exposed and unexposed groups . These negative results are explained by the fact that the observed e nvironmental factors are not mutagenic, at least not in the dosage whi ch was used, or the human zygote is not sensitive to mutagenic agents in the post-conceptional days.