Smooth endoplasmic reticulum aggregates in oocytes associated with increased risk of neonatal birth defects:...

Previous studies have indicated the association between smooth endoplasmic reticulum aggregates (SERa+) and poorer medically assisted reproduction outcomes. However, the link between SERa+ and neonatal outcomes remains controversial and open for debate. A comprehensive meta-analysis on the relation between SERa+ and the risk of birth defects is needed.

The literature search was conducted using the following databases: PubMed, Embase, Cochrane Libraries, Web of Science, and Chinese databases including China National Knowledge Infrastructure (CNKI) and Wan Fang from inception until July 2023. Risk ratio (RR) and 95% confidence interval (CI) were calculated by a fixed-effected model, while heterogeneity was assessed by forest plots and I² statistic. Funnel plot was produced to assess publication bias. This meta-analysis has been registered on PROSPERO (CRD42022313387).

The search resulted in 122 studies, 14 of which met the inclusion criteria. The analysis of birth defects revealed a higher risk (RR = 2.17, 95%CI 1.24 to 3.81, p = 0.007) in children derived from SERa+ cycle compared to SERa- cycles (711 vs. 4633). Meanwhile, in a subgroup analysis, the risk of birth defects was significantly increased in the SERa+ oocytes group as compared with the sibling SERa- oocytes group (RR = 3.53, 95%CI 1.21 to 10.24, p = 0.02).

To conclude, our analysis indicated that SERa+ cycles/oocytes may have a potential risk of increased additional major birth defects comparing with SERa- cycles/oocytes. This conclusion may provide evidence-based support for clinicians in IVF clinical guidance and embryologists in prudent embryo selection strategy.