Serum levels of polychlorinated biphenyls and some organochlorine insecticides in women with recent and former missed abortions.

Polychlorinated biphenyls and some organochlorine insecticides (DDT isomers and their metabolites, lindane (gamma-BHC), dieldrin, heptachlor epoxide) were assessed in the serum of 17 women with recent missed abortions, 7 women who experienced one or several missed abortions in their past, and 7 women with normal, second trimester pregnancy. Fifty-three percent of the cases of recent missed abortion had PCB serum levels higher than the mean plus two standard deviations of the control group. The mean PCB serum level in women with recent missed abortion and relatively high PCB serum levels was significantly different from that of the control group (103.04 versus 20.69 ppb, P less than 0.001). The mean PCB serum level of the former missed abortions group was also significantly different from that of the control group (82.00 versus 20.69 ppb, P less than 0.001). The quantity of the higher chlorinated biphenyl homologues (penta- and hexachlorobiphenyls) was increased in the high PCB level, missed abortion group and in the former missed abortion group, while the lower chlorinated biphenyl homologues were decreased in these groups in comparison with the control group. The percentage of total o,p'-DDT serum level, as related to total DDT, showed an increase in the high PCB level, recent missed abortion and in the former missed abortion groups, in comparison with the control group (36.18 and 48.98 versus 25.57, respectively). The fact that the former missed abortion group showed increased PCB serum levels similar to those found in the high PCB level, recent missed abortion group confirms the existence of an association between relatively high PCB serum levels and the occurrence of missed abortion. The possible role of PCBs in the occurrence of missed abortion is discussed.