Assisted Reproduction · Outcomes and Effectiveness

Interventions for unexplained infertility: a systematic review and network meta-analysis

Wang R, Danhof NA, Tjon-Kon-Fat RI, Eijkemans MJ, Bossuyt PM, Mochtar MH, van der Veen F, Bhattacharya S, Mol BWJ, van Wely M

Published September 5, 2019 The Cochrane database of systematic reviews, 9(9), CD012692
DOI 10.1002/14651858.CD012692.pub2 PMID 31486548 PMC PMC6727181
Read our synopsis

RRM Academy Synopsis

Insufficient evidence of a live birth gain in unexplained infertility

A Cochrane review of 27 trials found too little evidence that treatment beats waiting. Ten trials reported live birth. The review covered 4349 couples. In three trials of couples with poor odds of conceiving alone, IUI with ovarian stimulation and IVF/ICSI both raised live birth odds over waiting.

Key Findings

  • Ten trials (2725 couples) reported live birth. Against expectant management, odds ratios were 1.01 for ovarian stimulation (95% CI 0.51 to 1.98) and 1.21 for IUI (0.61 to 2.43), both low certainty.
  • Against expectant management, live birth odds ratios were 1.61 for ovarian stimulation with IUI (OS-IUI; 95% CI 0.88 to 2.94) and 1.88 for IVF/ICSI (0.81 to 4.38), both low certainty.
  • Three trials (725 couples, poor chance of conceiving unaided) found live birth OR 4.48 for OS-IUI (95% CI 2.00 to 10.1) and 4.99 for IVF/ICSI (2.07 to 12.04) versus expectant management.
  • Eleven trials (2564 couples) reported multiple pregnancy. Against expectant management/IUI, ovarian stimulation had OR 3.07 (95% CI 1.00 to 9.41; low certainty) and OS-IUI OR 3.34 (1.09 to 10.29; moderate).
  • For multiple pregnancy, IVF/ICSI against expectant management/IUI had OR 2.66 (95% CI 0.68 to 10.43), low certainty, which the authors call insufficient evidence of a difference.

Interpretation

The review pools randomized controlled trials and adds indirect comparisons through a network meta-analysis. Certainty ranged from low to moderate because estimates were imprecise and the couples in the trials had different clinical characteristics. Only ten trials reported live birth and eleven reported multiple pregnancy, out of 27. About half the trials appeared before 2000. The authors say old trials used intensive stimulation and loose cancellation criteria, and recent protocols led to fewer multiple pregnancies. The definition of unexplained infertility was broad and included mild endometriosis and mild male infertility. The poor-prognosis result comes from a post hoc sensitivity analysis of three trials.

RRM Context

The review calls infertility unexplained after routine tests only: semen, ovulation and tubes. It cites a 27% ongoing pregnancy rate over 12 months after those tests. Restorative reproductive medicine calls this undiagnosed and puts more evaluation of both partners first. Stimulation, insemination and IVF go ahead without finding why conception has not happened.

Abstract

Background

Clinical management for unexplained infertility includes expectant management as well as active treatments, including ovarian stimulation (OS), intrauterine insemination (IUI), OS-IUI, and in vitro fertilisation (IVF) with or without intracytoplasmic sperm injection (ICSI).Existing systematic reviews have conducted head-to-head comparisons of these interventions using pairwise meta-analyses. As this approach allows only the comparison of two interventions at a time and is contingent on the availability of appropriate primary evaluative studies, it is difficult to identify the best intervention in terms of effectiveness and safety. Network meta-analysis compares multiple treatments simultaneously by using both direct and indirect evidence and provides a hierarchy of these treatments, which can potentially better inform clinical decision-making.

Objectives

To evaluate the effectiveness and safety of different approaches to clinical management (expectant management, OS, IUI, OS-IUI, and IVF/ICSI) in couples with unexplained infertility.

Search Methods

We performed a systematic review and network meta-analysis of relevant randomised controlled trials (RCTs). We searched electronic databases including the Cochrane Gynaecology and Fertility Group Specialised Register of Controlled Trials, the Cochrane Central Register of Studies Online, MEDLINE, Embase, PsycINFO and CINAHL, up to 6 September 2018, as well as reference lists, to identify eligible studies. We also searched trial registers for ongoing trials.

Selection Criteria

We included RCTs comparing at least two of the following clinical management options in couples with unexplained infertility: expectant management, OS, IUI, OS-IUI, and IVF (or combined with ICSI).

Data Collection and Analysis

Two review authors independently screened titles and abstracts identified by the search strategy. We obtained the full texts of potentially eligible studies to assess eligibility and extracted data using standardised forms. The primary effectiveness outcome was a composite of cumulative live birth or ongoing pregnancy, and the primary safety outcome was multiple pregnancy. We performed a network meta-analysis within a random-effects multi-variate meta-analysis model. We presented treatment effects by using odds ratios (ORs) and 95% confidence intervals (CIs). For the network meta-analysis, we used Confidence in Network Meta-analysis (CINeMA) to evaluate the overall certainty of evidence.

Main Results

We included 27 RCTs (4349 couples) in this systematic review and 24 RCTs (3983 couples) in a subsequent network meta-analysis. Overall, the certainty of evidence was low to moderate: the main limitations were imprecision and/or heterogeneity.Ten RCTs including 2725 couples reported on live birth. Evidence of differences between OS, IUI, OS-IUI, or IVF/ICSI versus expectant management was insufficient (OR 1.01, 95% CI 0.51 to 1.98; low-certainty evidence; OR 1.21, 95% CI 0.61 to 2.43; low-certainty evidence; OR 1.61, 95% CI 0.88 to 2.94; low-certainty evidence; OR 1.88, 95 CI 0.81 to 4.38; low-certainty evidence). This suggests that if the chance of live birth following expectant management is assumed to be 17%, the chance following OS, IUI, OS-IUI, and IVF would be 9% to 28%, 11% to 33%, 15% to 37%, and 14% to 47%, respectively. When only including couples with poor prognosis of natural conception (3 trials, 725 couples) we found OS-IUI and IVF/ICSI increased live birth rate compared to expectant management (OR 4.48, 95% CI 2.00 to 10.1; moderate-certainty evidence; OR 4.99, 95 CI 2.07 to 12.04; moderate-certainty evidence), while there was insufficient evidence of a difference between IVF/ICSI and OS-IUI (OR 1.11, 95% CI 0.78 to 1.60; low-certainty evidence).Eleven RCTs including 2564 couples reported on multiple pregnancy. Compared to expectant management/IUI, OS (OR 3.07, 95% CI 1.00 to 9.41; low-certainty evidence) and OS-IUI (OR 3.34 95% CI 1.09 to 10.29; moderate-certainty evidence) increased the odds of multiple pregnancy, and there was insufficient evidence of a difference between IVF/ICSI and expectant management/IUI (OR 2.66, 95% CI 0.68 to 10.43; low-certainty evidence). These findings suggest that if the chance of multiple pregnancy following expectant management or IUI is assumed to be 0.6%, the chance following OS, OS-IUI, and IVF/ICSI would be 0.6% to 5.0%, 0.6% to 5.4%, and 0.4% to 5.5%, respectively.Trial results show insufficient evidence of a difference between IVF/ICSI and OS-IUI for moderate/severe ovarian hyperstimulation syndrome (OHSS) (OR 2.50, 95% CI 0.92 to 6.76; 5 studies; 985 women; moderate-certainty evidence). This suggests that if the chance of moderate/severe OHSS following OS-IUI is assumed to be 1.1%, the chance following IVF/ICSI would be between 1.0% and 7.2%.

Authors' Conclusions

There is insufficient evidence of differences in live birth between expectant management and the other four interventions (OS, IUI, OS-IUI, and IVF/ICSI). Compared to expectant management/IUI, OS may increase the odds of multiple pregnancy, and OS-IUI probably increases the odds of multiple pregnancy. Evidence on differences between IVF/ICSI and expectant management for multiple pregnancy is insufficient, as is evidence of a difference for moderate or severe OHSS between IVF/ICSI and OS-IUI.

Topics

By this author

Related research

Assisted Reproduction › Outcomes and Effectiveness › Outcomes by Diagnosis · Research Methods › Evidence Synthesis › Meta-Analysis
Marinus J C Eijkemans, Siladitya Bhattacharya, Ben W Mol, Madelon van Wely
M Eijkemans, S Bhattacharya, Benjamin Mol, B Mol, M Wely
PMID 31486548 31486548 DOI 10.1002/14651858.CD012692.pub2 10.1002/14651858.CD012692.pub2 Wang et al. 2019, Wang 2019

Cite this article

Wang, R., Danhof, N. A., Tjon-Kon-Fat, R. I., Eijkemans, M. J., Bossuyt, P. M., Mochtar, M. H., van der Veen, F., Bhattacharya, S., Mol, B. W. J., & van Wely, M. (2019). Interventions for unexplained infertility: a systematic review and network meta-analysis. The Cochrane database of systematic reviews, 9(9), CD012692. https://doi.org/10.1002/14651858.CD012692.pub2