pregnancy rate after endometrial injury in couples with unexplained infertility: a randomized clinical trial

background: unexplained infertility is still a challenging issue as to its causes, appropriate management and treatment. evidence implicates early embryopathy or implantation failure as likely causes. objective: this study aims to investigate the effect of local endometrial injury on pregnancy rate in selected unexplained infertile patients. materials and methods: this was a randomized clinical trial conducted in shiraz university infertility clinic of ghadir hospital. a total of 217 women with unexplained infertility aged 23-35 years old were randomly divided into two study groups through block randomization. after superovulation by clomiphene-citrate and gonadotropins and when the dominant follicles reached 18-20 mm, patients were randomly assigned to undergo endometrial local injury at posterior uterine wall by piplle endometrial sampling (n=114) or mock pipette biopsy (n=103) during pre-ovulatory days (when spontaneous urinary lh surge was detected). then all the patients were instructed to follow a regularly timed intercourse. results: the pregnancy rate was significantly higher in the endometrial injury group compared to the control group [17/114 (14.9%) vs. 6/103 (5.8%) (or: 2.83 95% ci: 1.07-7.49, p=0.03]. the abortion rate was comparable between two groups (17.64% vs. 14.28%; p=0.701). conclusion: local mechanical injury of the endometrium can enhance the uterine receptivity and facilitates the embryo implantation. this simple, easy, and cost effective procedure is worth considering in selective unexplained infertility patients who implantation failure is the likely causes of infertility before complex treatments. this procedure may help reduce psychological tensions and high expenses imposed through such interventions