Effects of aqueous leaf extract of Cajanus cajan on litter size and serum progesterone in pregnant rats

Aqueous leaf extract of Cajanus cajan is consumed by pregnant women in our locality. However, its effect on pregnancy has not been studied. C. cajan is known to contain genistein and diadzein which are potent phytoestrogens. We studied the effect of aqueous leaf extract of C. cajan on litter size and serum progesterone in pregnant rats. Oral administration of C. cajan on timed-pregnant rats increased litter size from 7.2 ± 1.1 in the control gorup to 10.1 ± 1.5 (p < 0.01) and 10.6 ± 0.8 (p < 0.003) in 100 and 200 mg/kg respectively. Serum progesterone increased from 98.6 ± 3.5 ng/ml in the control group to 112.4 ± 5.3 ng/ml (p < 0.003) and 114.2 ± 3.7 ng/ml (p < 0.002) in the 100 and 200 mg/kg treated groups respectively. There was reduction in litter weight from 6.93 ± 0.2 g in the control group to 4.60 ± 0.3 g (p < 0.0002) and 4.40 ± 0.1 g (p < 0.0003) in the 100 and 200 mg/kg treated groups respectively. There was no statistical significant difference in the litter weight among the treated groups. Aqueous extract of C. cajan caused reduced maternal weight gain in the treated group compared to the control. Maternal weight gain reduced from 62.4 ± 3.4 g in the control to 58.9 ± 2.8 g (p = 0.053) and 57.6 ± 3.1g (p < 0.05) in the 100 and 200 mg/kg treated groups respectively. There was no statistical significant difference in the litter weight among the treated groups. In conclusion, oral administration of aqueous leaf extract of C. cajan increases litter size and plasma progesterone in pregnant rats.