Intrauterine insemination + controlled ovarian hyperstimulation versus in vitro fertilisation in unexplained infertility: a systematic review and meta-analysis.

Background: IUI + COH is widely used in cases of unexplained infertility before resorting to IVF. Debate continues about what should be the first-line treatment for couples with unexplained infertility.

Objectives: This systematic review assessed the relative efficacy of IUI + COH compared with IVF in couples with unexplained infertility.

Search Strategy: We searched Medline, Embase, CIHNL, Pscy Info, and Cochrane Library from 1980 to November 2019.

Selection Criteria: Only RCTs published articles in full text with female patients aged 18-43 years and diagnosed with unexplained infertility were included.

Data Collection And Analysis: Two authors reviewed citations from primary search independently and any disagreement was resolved by mutual discussion and consultation with a third author.

Main Result: In total, eight RCTs were included. The quality of evidence was moderate to low due to inconsistency across the trials and imprecision. The pooled result showed that IVF was associated with a statistically significant higher live birth rate (RR 1.53, 95% CI 1.01-2.32, P < 0.00001 I = 86%) with no significant difference in multiple pregnancy rate or OHSS rate. Sensitivity analysis based on women's age and a history of previous IUI or IVF treatment showed no significant difference in the live birth rates (RR 1.01, 95% CI 0.88-1.15, I = 0%, 3 RCTs) in treatment-naïve women younger than 38 years. In women over 38 years, the live birth rates were significantly higher in the IVF group (RR 2.15, 95% CI 1.16-4.0, I = 42%, 1 RCT).

Conclusion: Further research using a standardised treatment protocol and taking into account important prognostic variables and cumulative live birth rates from fresh IVF and all sibling frozen embryos is required to further guide clinical practice.