BACKGROUNDThe relationship between intramural myomas and fertility remains unclear. The main debate rests on whether cavity-distorting intramural myomas (CDMs) adversely affect fertility more than non-CDMs. We aimed to compare the effects of enucleating non-CDMs and CDMs on fertility improvement in females with unexplained infertility.

METHODSWe prospectively recruited 83 women undergoing myomectomy for unexplained infertility with intramural myomas between June 2008 and November 2012 and classified them into non-CDMs group (n = 45) and CDMs group (n = 38). We then compared postoperative infertility rates, spontaneous pregnancy rates, pregnancy outcomes, live birth rates, and obstetric complications. For continuous variables, we calculated the mean ± standard deviation, median and interquartile range, and analyzed the data using Student's t-test and the Mann-Whitney U-test. For categorical variables, the Pearson's Chi-square test, the continuity correction test, and Fisher's exact test were used.

RESULTSPatients' demographics and myoma characteristics were comparable between the two groups. The overall spontaneous pregnancy rate increased from 0% to 68.42% following myomectomy. The postoperative infertility rate was significantly higher in the non-CDMs group than that in the CDMs group (50.00% vs. 23.53%, t = 5.579, P = 0.018), whereas the postoperative spontaneous pregnancy rate was significantly lower in the non-CDMs group than that in the CDMs group (47.62% vs. 70.59%, t = 4.067, P = 0.044). Compared with the enucleation of non-CDM, the enucleation of CDM patients was a protective factor for the fertility restoration (risk ratio [RR] = 3.717, 95% confidence interval [CI]: 1.284-10.753, P = 0.015), although postoperative fertility restoration declined with age (RR = 1.141, 95% CI: 1.005-1.295, P = 0.041).

CONCLUSIONSIntramural myomas are associated with impaired fertility. Women experiencing unexplained infertility, and possessing intramural myomas, have a better chance of conception following myomectomy, and these benefits are more obvious for younger patients and patients with CDM.