Dibromochloropropane-induced reduction of the sex-ratio in man.

The present study evaluated the effect of paternal exposure to Dibromochloropropane (DBCP) during its production, on the sex ratio of offsprings conceived during the exposure period. The study population consisted of 30 families of which 13 fathers became azoospermic, 8 oligozoospermic and 9 normozoospermic. Of the 89 pregnancies recorded, 68 culminated in the birth of live infants. The prevalence of male infants conceived during the pre-exposure period was 52.9% , in contrast to 35.2% for boys conceived during exposure. For the combined azoospermic and oligozoospermic groups, a significantly low prevalence of male infants of 16.6% (p less than 0.025) was found. It is concluded that paternal exposure to DBCP during its production process is associated with a significant decrease in the sex ratio of offsprings conceived during the exposure period. This drop in the sex ratio might be a reflection of the early effect of DBCP on male reproductive performance before a state of severe testicular dysfunction and infertility is reached.