OBJECTIVETo investigate the effect and explore the mechanism of Bushen Antai Recipe (BAR) on pregnancy rate and number of implantation site in blastocyst implantation dysfunction (BID) mice induced by indomethacin.

METHODSPregnant mice were divided into 3 groups randomly: the normal group, the model group and the BAR group. Tap water was given orally to the rats in the normal and model groups, and BAR to the rats in the BAR group from the first day of pregnancy for 5 or 8 days; on the 3rd and 4th day dissolvent was injected subcutaneously twice per day in the normal group, while indomethacin (4.33 mg/kg) was injected subcutaneously twice per day in the other two groups to establish implantation dysfunction model; serum estrogen (E) and progesterone (P4) levels were detected on the 5th and 8th day; the pregnancy rate and number of implanted site was observed and the receptors of E and P4 in endometrium of uterus were examined by immunohistochemistry on the 8th day.

RESULTSThe pregnancy rate and number of implanted site was 27.3% and 5.3 +/- 0.7 respectively in the model group, significantly lower than those in the normal group (90.9%, 13.3 +/- 2.8), and the BAR group (72.7%, 10.7 +/- 2.2, P < 0.05). Serum E level was higher in the BAR group than that in the model group on the 5th and 8th day, and even higher than that in the normal group on the 8th day; serum P4 level was lower in the model and BAR groups than that in the normal group on the 5th day (P < 0.01), but higher in the BAR group than that in the model group on the 8th day. Immunohistochemical observation showed that expressions of E and P4 receptor increased remarkably in the BAR group than those in the model group.

CONCLUSIONBAR increases the pregnancy rate and number of implanted site of indomethacrne induced BID mice through regulating E and P4 levels and enhancing the expressions of their receptors in the endometrium.