Effects of an aqueous extract of trunk bark of Ficus religiosa on fertility of rats

Some native physicians in Sri Lanka claim that a water extract of the bark of Ficus religiosa has antifertility activity in males and post-coital cont raceptive activity in females. The aim of this study was to validate this c laim scientifically. A thrice a day, oral administration, for 7 consecutive days, of 1 ml of 500 mg/kg of extract to rats did not inhibit libido, sexu al performance tin terms of % mounted, % intromitted, % ejaculated, number of mounts, number of intromissions, mount latency, intromission latency, ej aculation latency, copulatory efficiency or intercopulatory interval) or fe rtility (as judged by quantal pregnancy, fertility index, number of uterine implants, implantation index, or vaginal sperm counts) on days 1, 4 and 7 of treatment. On the other hand, the same treatment when given to pregnant rats from days 1 to 7 of gestation had marked post-coital contraceptive act ivity (in terms of quantal pregnancy (by 58%) and number of uterine implant s (by 58%) and number of pups born (by 63%). The lower dose (250 mg/kg) had no post-coital contraceptive activity. The post-coital contraceptive activ ity of the extract was due to a profound elevation of pre-implantation loss es mediated via powerful rhythmic contractions of the uterine musculature ( as indicated by organ bath experiments) and not by oestrogenic mechanisms ( as determined by wet uterine weights and vaginal cytology). Furthermore, th e extract was well tolerated, as determined by overt clinical signs of toxi city, aberrant behaviour patterns, muscle strength and liver function tests . We conclude that the extract has post-coital contraceptive activity but n o antifertility effects in the male. Ficus religiosa bark is a promising et hnobotanical source for the development of new, safe, orally active, post-c oital contraceptive agents. Med Sci Res 27:349-353 (C) 1999 Lippincott Will iams & Wilkins.