Male adiposity impairs clinical pregnancy rate by in vitro fertilization without affecting day 3 embryo quality

Abstract

Objective: Male adiposity is detrimental for achieving clinical pregnancy rate (CPR) following assisted reproductive technologies (ART). The hypothesis that the association of male adiposity with decreased success following ART is mediated by worse embryo quality was tested. Design and Methods: Retrospective study including 344 infertile couples undergoing in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) cycles was performed. Cycle determinants included number of oocytes retrieved, zygote PN-score, total number of embryos available on day 3, number of embryos transferred, composite day 3 grade for transferred embryos, composite day 3 grade per cycle, and CPR. Results: Couples with male body mass index (BMI) over 25 kg m À2 (overweight and obese) exhibited significantly lower CPR compared to their normal weight counterparts (46.7% vs. 32.0% respectively, P ¼ 0.02). No significant difference was observed for any embryo quality metrics when analyzed by male BMI: mean zygote PN-scores, mean composite day 3 grades for transferred embryos or composite day 3 grades per cycle. In a multivariable logistic regression analysis adjusting for female age, female BMI, number of embryos transferred and sperm concentration, male BMI over 25 kg m À2 was associated with a lower chance for CPR after IVF (OR ¼ 0.17 [95% CI: 0.04-0.65]; P ¼ 0.01) but not after ICSI cycles (OR ¼ 0.88 [95% CI: 0.41-1.88]; P ¼ 0.75). In this cohort, male adiposity was associated with decreased CPR following IVF but embryo quality was not affected. Conclusions: Embryo grading based on conventional morphologic criteria does not explain the poorer clinical pregnancy outcomes seen in couples with overweight or obese male partner.

Effects of obesity on sperm retrieval, early embryo quality and clinical outcomes in men with nonobstructive azoospermia undergoing testicular sperm aspiration‐intracytoplasmic sperm injection cycles

“…In addition, there was no significant difference in early embryo quality or clinical outcomes according to male BMI, with strict inclusion criteria for corresponding females to avoid the interference of female factors with oocyte and embryo development. Several related reports have suggested the lack of significant differences in embryo quality metrics (Merhi et al, ) or fertilisation rates (Braga et al, ; Umul et al, ) according to male BMI among infertile couples undergoing IVF or ICSI cycles. Data from a study by Hassan W. Bakos also showed no relationship between male BMI and embryo quality in the cleavage stage until day three (Bakos, Henshaw, Mitchell, & Lane, ), which may be due to male genome activation after the 4‐ to 8‐cell stage in humans (Artley, Braude, & Johnson, ).…”

Obesity and reproduction: a committee opinion

“…Moreover, increased abdominal adiposity in men of subfertile couples has been associated with reduced sperm count, concentration, and motility (90). Evidence, however, varies as to whether male obesity alters sperm function (98), increases sperm DNA damage (91,(99)(100)(101)(102)(103), decreases sperm mitochondrial activity (101,102), induces seminal oxidative stress (104), impairs blastocyst development (85), reduces pregnancy outcome, or increases miscarriage following assisted reproduction (85,87,91,98,(105)(106)(107)(108). These discrepancies likely represent differences in data acquisition, study populations, patient lifestyles, and comorbidities (98).…”

Association between obesity and sperm quality

“…The altered ratio of testosterone and oestrogen levels thus has profound effect on spermatogenesis (Aggerholm, Thulstrup, Toft, Ramlau‐Hansen, & Bonde, ; Fejes et al., ; Hinz et al., ; Hofny et al., ; Jensen et al., ; Pauli et al., ). The influence of male obesity is not limited to immediate end points such as pregnancy (Merhi et al., ), time to conceive (Nguyen, Wilcox, Skjaerven, & Baird, ; Ramlau‐Hansen et al., ) and live births (Bakos et al, ), but may affect metabolic profiles and fertility levels in future offspring (Danielzik, Langnase, Mast, Spethmann, & Muller, ; Fullston et al., ; Li, Law, Lo, & Power, ). Craig, Jenkins, Carrell, and Hotaling () reviewed the role of obesity in sperm epigenetic perturbations.…”