The effectiveness and safety of Chinese herbal medicine in infertile women with luteal phase deficiency: a systematic review and meta-analysis

Background: Chinese herbal medicine (CHM) has been reported to treat infertile women with luteal phase deficiency (LPD) in some clinical studies, however, the efficacy and safety of CHM for LPD are still under controversy. Here, we aim to evaluate the efficacy and safety of CHM using meta-analysis, and further compare it with conventional Western therapies (CWT) to elucidate the improvement in progestin and clinical pregnancy rates. Methods: Eight randomized controlled trials (RCTs) involving 465 women were included in our systematic review; these RCTs compared CHM with CWT in treating LPD in infertile women. The methodological quality of the included RCTs was assessed according to the Cochrane risk-of-bias assessment criteria. The data were analyzed by Review Manager 5.3 software. We estimated the risk ratio (RR) for dichotomous data and calculated the mean difference for continuous data. Results: In contrast to CWT, CHM was superior in improving clinical pregnancy rates (RR 0.19; 95% CI: 0.11-0.27; P<0.001), increasing progesterone levels in the luteal phase [mean difference (MD) 2.28; 95% CI: 1.91-2.64; P<0.001] and luteal phase estrogen (MD 9.88; 95% CI: 4.53-15.24; P=0.0003), reducing traditional Chinese medicine (TCM) syndrome scores (MD -3.06; 95% CI: -3.95 to -2.17; P<0.001), and the incidence of adverse reactions (RR 0.12; 95% CI: 0.02-0.70; P=0.02). Conclusions: Evidence from eight small studies suggested that CHM has a therapeutic effect on infertile women with luteal insufficiency. We indicated that CHM may improve the level of progesterone and estradiol in the luteal phase, and the clinical pregnancy rate, with few side effects based on the current studies. However, given the relatively small number of included studies, further studies about the higher quality of study designs, larger population and the underlying mechanism are required to elucidate the role of CHM in LPD treatment.