Decreased DNA Repair Ability: A Mechanism for Low Early Embryonic Development Potential of Oocytes From Overweight Patients After Fertilization in IVF Cycles

Abstract

BackgroundWhether female BMI impacts the DNA repair ability in the oocytes after fertilization has not been investigated. The aim of this study is to assess the early embryo quality and reproductive outcomes of oocytes from overweight women when fertilized with sperm with varying degrees of DNA fragmentation.MethodsA total number of 1,612 patients undergoing fresh autologous in vitro fertilization (IVF) cycles was included. These patients were divided into two groups according to maternal body mass index (BMI): normal weight group (18.5–24.9 kg/m2; n=1187; 73.64%) and overweight group (≥25 kg/m2; n=425; 26.36%). Each group was then subdivided into two groups by sperm DNA fragmentation index (DFI): low fragmentation group (<20% DFI, LF) and high fragmentation group (≥20% DFI, HF). Laboratory and clinical outcomes were compared between subgroups.ResultsFor the normal-weight group, there was no statistical significance in embryo quality and reproductive outcomes between the LF and HF groups. But in the overweight group, significantly lower fertilization rate (LF: 64%; HF: 59%; p=0.011), blastocyst development rate (LF: 57%; HF: 44%; p=0.001), as well as high-quality blastocyst rate (LF: 32%; HF: 22%; p=0.034) were found in the HF group, despite the similar pregnancy rates (LF: 56%; HF: 60%; p=0.630).ConclusionsDecreased DNA repair activity in oocytes may be a possible mechanism for the low early development potential of embryos from overweight patients in in vitro fertilization cycles.

The impact of female BMI on sperm DNA damage repair ability of oocytes and early embryonic development potential in intracytoplasmic sperm injection cycles

“…However, in overweight/obese women, lower fertilization rate, cleavage rate, and high-quality embryo rate were observed in DFI≥30% cycles than in DFI<30% cycles. These findings are congruent with prior research on IVF cycles at our center ( 26 ), which revealed that in patients with normal weight, there was no statistically significant difference in the different levels of sperm fragmentation in terms of embryo quality and reproductive outcomes. However, in overweight patients, the high-fragmentation group had much lower rates of fertilization, blastocyst development, and high-quality blastocysts than the low-fragmentation group.…”

High-DNA Stainability Is Not Related to Embryonic Development and Clinical Outcomes on In Vitro Fertilization Cycles: A Retrospective Study Using a Propensity Score-Matching Analysis

“…Univariate linear regression analysis showed that fertilization rate was the only parameter among IVF outcomes significantly but weakly affected by HDS, while there was no correlation between fertilization rate and HDS after adjusting. This might be because the effect in univariate model was caused by female factors rather than HDS, given the small contribution of HDS to the equation in which the coefficient of determination (R 2 ) was 0.02 (data not shown) and the large and well-established role of female factors (such as advanced age, obesity, and poor ovarian reserve) in fertility [37][38][39]. Thus, the actually prognostic value of sperm HDS on fertilization was observed after adjusting.…”