Association between sperm DNA fragmentation index and spontaneous miscarriage following IVF-ET: a retrospective...

To investigate the correlation between sperm DNA fragmentation rate and different types of spontaneous miscarriage after In Vitro Fertilization and Embryo Transfer (IVF-ET).

A retrospective analysis was conducted on clinical data from 2,128 patients undergoing in vitro fertilization-embryo transfer treatment at the Reproductive Center of Qingdao Women and Children's Hospital. Patients were categorized into groups based on pregnancy outcomes and types of spontaneous miscarriage, including an ongoing pregnancy group, biochemical pregnancy group, spontaneous miscarriage group (unknown cause), and spontaneous miscarriage group (embryonic chromosomal abnormality). Differences in the sperm DNA fragmentation index (DFI) among these groups were analyzed and DFI was assessed using the Sperm DNA Fragmentation Detection Kit. Adjustment for confounding factors was performed using multivariable regression analysis and propensity score matching.

Univariate analysis revealed that the DFI in the spontaneous miscarriage group (unknown cause) was higher than that in the ongoing pregnancy group (P = 0.006). Multivariable analysis indicated that sperm DFI (odds ratio (OR) 1.011, 95% confidence interval (CI) [1.001-1.021]) was independently associated with spontaneous miscarriage (unknown cause). Propensity score matching analysis demonstrated that even after predefined conditional matching, the DFI in the spontaneous miscarriage group (unknown cause) remained higher than that in the ongoing pregnancy group (P = 0.042). However, receiver operating characteristic (ROC) curve analysis showed that DFI was a poor discriminator for unexplained miscarriage, with an area under the curve of just 0.556 (95% CI [0.516-0.596]), which is only marginally better than chance.

Sperm DFI shows a statistical association with IVF-ET spontaneous miscarriage of unknown cause, but its discriminatory capacity is negligible and it is not a clinically useful predictor. Sperm DFI showed no significant association with biochemical pregnancy or spontaneous miscarriage with embryonic chromosomal abnormality.