Exposure to beta-cypermethrin impairs the reproductive function of female mice.

This study aimed to investigate the effects of beta-cypermethrin (ß-CYP) on female reproductive function and examine the morphology of the uterine endometrium and follicular development. The results found that the rate of successful pregnancy in the ß-CYP-treated groups significantly decreased. The levels of serum E2 and FSH were significantly increased in the ß-CYP-treated groups. The concentrations of serum P and LH were significantly decreased in the ß-CYP-treated groups. The uterine endometrium was damaged and the endometrial pinopode was markedly inhibited. In addition, the total number of follicles of all types was significantly lower in the medium- and high-dose ß-CYP-treated groups. These results suggest that ß-CYP significantly affected the reproductive function of female mice. ß-CYP may have significantly decreased the fertility of female mice by disturbing the reproductive hormone concentrations and inhibiting the development of the endometrium and the endometrial pinopode.

Effect of beta-cypermethrin exposure on embryo implantation in mice.

The aim of this study was to investigate the effect of ß-CP on embryo implantation in mice. Forty female mice were randomly assigned to four groups of 10 mice each: one control group and three ß-CP treated groups. The control group was administered corn oil only, while the three ß-CP-treated groups were given corn oil containing 5, 10, and 20 mg/kg bw d ß-CP for 3 months through intragastric administration. The results indicated that the administration of ß-CP decreased the rate of embryo implantation (all p < 0.05), E2 level in the serum, and the expression of Homeobox A10 (HoxA10) protein. In addition, ß-CP significantly increased ERa and PRA protein expression levels. These results suggest that ß-CP can disrupt the balance of E2 and P, influence ERa and PRA expression and their downstream-related molecule Hoxa10, and decrease embryo implantation.