The post-implantational effects of dinoseb, PCBs (Aroclor 1254), rotenone and zineb on reproductive systems were examined using decidualized pseudopregnant rat as a model. Uterine protein, uterine glycogen, uterine water, and ovarian protein were studied in day 10 decidualized pseudopregnant rats fed the toxicants from days 6 through 9 of pseudopregnancy. Dinoseb reduced uterine protein and uterine glycogen in rats fed 25 ppm and higher concentrations. Uterine water and uterine weight were reduced at the highest dosage of 750 ppm. Ovarian protein was diminished at 150 ppm and higher concentrations. PCBs lowered uterine glycogen, but uterine protein content was not reduced in a dose-related manner. Ovarian protein content was diminished at 50 ppm and higher concentrations. Uterine weight and uterine water were not changed in rats fed up to 1000 ppm of the PCBs. Rotenone reduced uterine protein in rats fed 200 ppm and higher concentrations. In day-16 pregnant rats fed rotenone (100, 200, 400, and 600 ppms) from days 6-;6 of pregnancy, placental protein, placental glycogen, ovarian protein, and maternal body weight were reduced. Additionally, these dosing regimens reduced fetal survival rate. Fetal weight of fetus delivered from rotenone-fed dams was not affected. The decidualized pseudopregnant uterine, and placental functions, and fetal survival rate of rats were not affected by zineb up to 2500 ppm.