Antifertility effects of crude extracts from Acacia nilotica pods and Albizia lebbeck stem bark in female multimammate rats, Mastomys natalensis

The study's main objective was to assess any pathophysiological significance of Acacia nilotica pods aqueous extract and Albizia lebbeck stem bark methanolic extract on the reproductive system of female multimammate rats (Mastomys natalensis). A total of 60 sexually mature female rats were randomized into a 2 × 3 factorial experimental design for treatments (Control, A. nilotica, and A. lebbeck) and treatment duration (7 or 14 days). Control rats consumed basal feed only, whereas extract-treated rats consumed the basal feed containing 2% w/w of either of the two plant extracts. At the end of treatment duration, treated female rats were cohabited with males for 16 days and sacrificed 20 days after the first day of cohabitation. Parameters including pregnancy rates, number of fetal implantations, possible resorption sites and fetal litter size were assessed at necropsy. Further post-necropsy parameters were evaluated in ovaries including the ovarian weights, follicular and corpora lutea numbers and general histopathology. Results showed that pregnancy percentages, the number of fetal implantations and fetal litter size were significantly reduced (P 0.05). However, the number of corpora lutea of pregnancy was significantly reduced (P < 0.001) in ovaries of rats under extract treatments than in their control counterparts. Instead, ovaries of rats receiving the two extracts contained a larger number of degenerating follicles, signifying halted ovulatory and conception activities. The current study has demonstrated that dietary inclusion of crude extracts from A. nilotica pods and A. lebbeck stem bark can lead to decreased fertility success rates in M. natalensis female rats through suppression of ovulatory activities and induction of follicular atresia. Key words: Rodent pests, medicinal plants, fertility success, reproductive system.