The effect of uterine adenomyosis on IVF outcomes: a systematic review and meta-analysis

To investigate the impact of uterine adenomyosis on in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) clinical outcomes and also to evaluate the impact of gonadotropin-releasing hormone agonist (GnRHa) and surgical treatments. Infertile women with adenomyosis undergoing conventional IVF or ICSI were compared with women without adenomyosis. Fertility outcomes were evaluated in two patients with adenomyosis untreated and treated surgically or medically therapy. The review protocol was registered in PROSPERO (CRD42020214586). We consider the live birth rate (LBR) as the primary outcome. The analysis showed that women with adenomyosis had lower LBR (OR 0.59, 95% CI 0.37-0.92, p = 0.02), clinical pregnancy rate (OR 0.66, 95% CI 0.48-0.90), and ongoing pregnancy rate (OR 0.43, 95% CI 0.21-0.88) compared to those without adenomyosis, and miscarriage rate was higher in women with adenomyosis (OR 2.11, 95% CI 1.33-3.33). Surgical treatment increases natural conception in women with adenomyosis although the paucity of data (only two studies), and conversely, treatment with GnRHa does not increase the IVF outcomes. Women with adenomyosis have decreased IVF clinical outcomes. Pretreatment with the use of long-term GnRHa could not be beneficial, even though only three studies were included in the meta-analysis. The major part of the studies has not divided focal and diffuse adenomyosis, and this represents a relevant source of bias: studies conducted with standardized diagnostic criteria for adenomyosis are still needed to determine if the different clinical presentations of such condition could compromise IVF outcomes.