Repairing a varicocele may help a couple conceive — but the evidence is shaky

For a subfertile man with a varicocele — a tangle of enlarged veins in the scrotum — surgery or a radiological procedure to fix it may modestly improve his partner's chance of pregnancy, but the evidence is weak and does not confirm that it results in more babies actually born [s1]. A 2021 Cochrane review of 48 trials in 5,384 men found treatment may raise pregnancy rates, while the effect on live birth stayed uncertain [s1].

What a varicocele is

Varicoceles are common and are associated with reduced fertility, though, as the Cochrane authors note, exactly how they impair sperm production has never been satisfactorily explained [s1]. Because many men with a varicocele are perfectly fertile, the clinical question is narrow: in a couple who cannot conceive, where the man has a varicocele and the woman has no fertility problem of her own, does repairing it help? The AUA/ASRM guideline treats varicocele repair as one option within the broader management of male infertility, alongside assisted reproduction such as IUI, IVF and ICSI [s2].

What the trials show

The honest summary is "maybe, for pregnancy; unproven, for live birth." Pooling 13 randomised trials in 1,193 men, Cochrane found treatment may improve pregnancy rates compared with delayed or no treatment, with a risk ratio of 1.55 (95% CI, 1.06–2.26) — but rated the certainty low [s1]. In plain terms, that translates to couples having roughly a 21% chance of pregnancy with no or delayed treatment, rising to somewhere between 22% and 48% after repair [s1]. The width of that range is the point: the benefit could be trivial or substantial, and the data cannot tell which.

For the outcome couples care about most — a live birth — the evidence effectively vanishes. Only two small trials in 204 men addressed it, pointing in opposite directions, leaving a risk ratio of 2.27 with a 95% confidence interval running from 0.19 to 26.93 [s1]. That is not a finding; it is a shrug. Cochrane rated it very low certainty [s1].

Which procedure, if any

The review could not establish that surgery beats a radiological approach (embolisation): for pregnancy the two were statistically indistinguishable, risk ratio 1.13 (95% CI, 0.75–1.70) across 5 trials in 456 men [s1]. Where the evidence was firmer was in comparing surgical techniques with each other. Microscopic subinguinal surgery — the microsurgical approach — probably improves pregnancy rates slightly over other surgical methods (risk ratio 1.18; 95% CI, 1.02–1.36; 12 trials, 1,473 men; moderate certainty), lifting the pregnancy rate from about 10% to 10–14% [s1]. It also probably cuts the chance the varicocele comes back, with 0.4% to 1.1% of men recurring after microsurgery versus 1.4% after other operations (risk ratio 0.48; 95% CI, 0.29–0.79; moderate certainty) [s1]. Radiological techniques were barely tested against each other at all: a single 30-man trial comparing sclerotherapy with embolisation reported 13% recurrence in both groups, too little to draw any conclusion [s1].

This was a large undertaking — the reviewers screened 1,897 citations and folded 38 new studies into the 10 from the previous version — which makes the persistent uncertainty a statement about the primary trials, not the review [s1]. Most were small, and their methods varied enough that even the pooled estimates carry low confidence.

The limits

Almost every estimate here rests on low or very low certainty evidence, small trials, and inconsistent results — the review's authors explicitly called for high-quality head-to-head trials measuring live birth [s1]. That matters because a couple weighing surgery against going straight to assisted reproduction is making a real trade-off, and the data do not clearly favour either path.

What it means

A varicocele repair is a reasonable option for the right subfertile man, and if it is done, microsurgery has the best-supported balance of results [s1]. But no one should be promised a baby from it: the pregnancy benefit is real but imprecise, and the live-birth benefit is simply unproven [s1]. As with much of male-factor infertility, the evidence base is thinner than the confidence with which treatments are sold — the same gap that runs through the wider risk factors for poor semen quality, the contested claim that sperm counts are collapsing, and consumer worries from scrotal heat to chemical exposures.

Sources

• [s1] Cochrane Database of Systematic Reviews — Surgical or radiological treatment for varicoceles in subfertile men (2021-04-23)
• [s2] Journal of Urology (AUA/ASRM) — Diagnosis and Treatment of Infertility in Men: AUA/ASRM Guideline Part II (2020-12-09)