Do young women with unexplained infertility show manifestations of decreased ovarian reserve?

PurposeTo investigate whether unexplained infertility at a young age demonstrates manifestations of decreased ovarian reserve.MethodsA total of 100 women were divided into two equally sized groups. The study group comprised women aged ≤ 37 years diagnosed with unexplained infertility, and the control group included age-matched women with either mechanical factor or severe male factor infertility.ResultsBoth groups were comparable in their basic characteristics. Overall, women with unexplained infertility presented with inferior ovarian reserve results set against women of the control group. The number of ≥ 14-mm follicles on the day of hCG administration was significantly lower in the study compared with the control group (7.0 ± 4.5 vs. 10.4 ± 4.1 follicles, respectively, P < 0.001). Likewise, basal serum FSH was higher in the study compared with the control group (8.4 ± 5.5 vs. 6.4 ± 1.7 IU/L, respectively, P = 0.015), while antral follicle count was lower (10.9 ± 6.6 vs. 16.2 ± 6.6 follicles, respectively, P < 0.001). Furthermore, women with unexplained infertility required a higher total dose of FSH for ovarian stimulation (2,923 ± 1,701 vs. 2,196 ± 941 IU/L, respectively, P = 0.010), but exhibited a lower number of retrieved oocytes (9.3 ± 6.3 vs. 15.6 ± 7.9 oocytes, respectively, P < 0.001), alongside a lower number of achieved embryos (5.3 ± 4.0 vs. 8.0 ± 4.7 embryos, respectively, P = 0.002). Interestingly, the cumulative clinical pregnancy rate was not significantly different between the two groups (44% vs. 58%, respectively, P = 0.163).ConclusionsYoung women ≤ 37 years of age with unexplained infertility have clear manifestations of sub-optimal ovarian reserve set against controls. Our findings suggest that unexplained infertility at a young age may be a risk factor for developing poor ovarian response, specifically as a quantitative, rather than a qualitative, risk factor.