Phase-dependent effects of purwoceng (Pimpinella alpina KDS) on estrous cycle modulation in virgin female rats

Purwoceng (Pimpinella alpina KDS) is a traditional medicinal herb that has been widely studied for its androgenic properties in male reproductive research. However, their effects on female reproductive performance remain poorly understood. This study aimed to investigate the influence of purwoceng on the duration of each estrous phase and the overall estrous cycle in female rats. Forty-eight virgin female Sprague-Dawley rats were allocated into four groups according to their estrous phase at the start of treatment: proestrus, oestrus, metestrus, and diestrus. Each group consisted of six control and six Purwoceng-treated animals. The extract was administered intragastrically for ten consecutive days, while vaginal smear evaluations continued until day 15 to monitor estrous cyclicity. The results demonstrated that purwoceng administration during the two estrous cycles generally prolonged the proestrus and oestrus phases, with a statistically significant extension of the oestrus phase observed when treatment was provided during oestrus (P < 0.05). Conversely, the durations of the metestrus and diestrus phases were reduced, except when Purwoceng was administered during metestrus, which resulted in an increased metestrus duration. In conclusion, purwoceng exhibited the greatest modulatory effect when administered during the oestrus phase, suggesting a phase-dependent responsiveness of the female reproductive cycle to this herbal extract.