Unexplained infertility categorization based on female laparoscopy and total motile sperm count, and its impact on cumulative live-births after one in-vitro fertilization cycle. A retrospective cohort study involving 721 cycles.

Purpose: To determine how subcategorizing unexplained infertility based on female laparoscopy and total-motile-sperm-count assessment would impact cumulative live-births after one in-vitro fertilization (IVF) cycle.

Methods: Seven hundred twenty one IVF cycles from Jan 2014-April 2019 performed at a single-center were retrospectively analyzed. Couples with unexplained infertility having normal uterine and endometrial morphology were subcategorized into three cohorts, UI (1): those with no tuboperitoneal pathology on laparoscopy and total-motile-sperm-count (TMSC) ≧20 million: n = 103; UI (2): tuboperitoneal pathology on laparoscopy or TMSC <20 million, n = 86; and UI(3): tuboperitoneal status not known: n = 114. Controls were severe male factor, bilateral tubal block, and grade 3/4 endometriosis: n = 418. Primary Outcome was cumulative-live-birth-per-initiated-IVF cycle (CLBR). Odds ratio for live-births were adjusted for confounding factors.

Results: The CLBR in UI1 cohort was significantly lower than controls (29.1% vs 39; OR = 0.62; 95%CI = 0.39-0.98;  = .04); but similar in UI2 and UI3 vs. controls. (37.2% vs 39.95%; OR = 0.89, 95%CI = 0.55-1.44;  = .89) and (38.6% vs 39.95%; OR = 0.98, 95%CI = 0.64-1.55;  = .98). After adjusting for age, infertility duration, past live-births, and AMH, the adjusted odds for CLBR in UI1 was 0.48 (95%CI = 0.28-0.82;  = .007).

Conclusions: Unexplained infertility when defined after a normal laparoscopy and TMSC significantly lowered cumulative-live-births-per-initiated-IVF cycle when compared with traditional diagnosis of tubal, endometriosis, or male factor infertility. In UI subcategory with abnormal laparoscopy or TMSC, CLBR remained unaffected. This information could be useful for counseling couples prior to IVF. Large-scale prospective studies are needed to confirm this observation.