Background: The search for a relatively cheap, widely available, widely accepted and effective contraceptive of plant origin; that is equally non-invasive in administration, non-hormonal in action, non-toxic and that is relatively long-acting, generated our interest in this study (in order to meet the increasing need for population control). The aim of this study was to determine the effects of alcoholic extract of Neem flowers on the estrous cycle, ovulation, fertility and foetal morphology of cyclic adult Sprague-Dawley rats.
Materials and methods: Adult female Sprague-Dawley rats, weighing between 140-180 g were used. There were 3 main experimental groups. Group 1 rats received 1 g/kg of alcoholic extract of Neem flower by gavage for 3 weeks and the effect on estrous cycle studied. Group 2 rats were administered 1 g/kg of Neem flower alcoholic extract at 9 a.m. and at 6 p.m. on proestrus and the effect on the number of ova shed on the morning of estrus observed. Rats in Group 3 were treated with 1 g/kg of alcoholic extract of Neem flower on days 1 to 5 postcoitum, and observation was made for anti-implantation / abortifacient effects and possible teratogenic effects on the foetuses. All the groups were control-matched.
Results: The estrous cycle of 80% of the rats was altered with a marked prolongation of the diestrus phase. Neem flower caused a statistically significant (p < 0.05) reduction in the number of ova shed in the morning of estrus in rats fed with the extract at 9 a.m. on proestrus. Neither anti-implantation / abortifacient nor teratogenic effect was observed in the rats treated with Neem flower.
Conclusion: Administration of alcoholic extract of Neem flower disrupted the estrous cycle in Sprague-Dawley rats and caused a partial block in ovulation and thus has the potential of being developed into a female contraceptive.