The effects of Garcinia kola
seed extract on oestrous cycle, ovulation and foetal development were studied in adult female Sprague-Dawley (S-D) rats. Cyclic female rats weighing 150 to 200g were divided into three experimental groups and a control group. Group 1 was fed with 200mg/kg body weight of theextract on proestrous. Group 2 received 200mg/kg body weight of the extract daily for six weeks, while group 3, consisted of pregnant rats which received the same dose of the extract on days 1-5, 7-9th
day of gestation. In groups 1 and 2, vaginal lavage was taken daily to monitor the oestrous cycle and ovulation. In group 3, gestational parameters monitored were number of total implants, resorption and dead foetuses. Live foetuses were weighed and examined for external malformation and variation. The results showed that the oestrous cycle was altered for the first two weeks after commencement of extract but returned to normal from the third week. This was indicated by the irregular pattern of oestrous with a prolonged dioestrus observed in the treated rats. Ovulation was partially blocked as shown by the reduced number of ova observed in the oviduct from the treated rats compared with control (p< 0.05). There was a significant decrease in the weight of foetuses from the treated rats (p <0.05) while 7% of the foetuses from pregnant rats, which received treatment for the first five days of gestation, had malformed left upper limb. Results suggest that G. kola
seed at 200mg/kg body weight administered alters oestrous cycle in rats, partly inhibits ovulation and may produce duration dependent teratogenicity in foetal rats.