Paternal obesity negatively affects male fertility and assisted reproduction outcomes: a systematic review and meta-analysis

Abstract

This systematic review investigated the effect of paternal obesity on reproductive potential. Databases searched were Pubmed, Ovid, Web of Science, Scopus, Cinahl and Embase. Papers were critically appraised by two reviewers, and data were extracted using a standardized tool. Outcomes were: likelihood of infertility, embryo development, clinical pregnancy, live birth, pregnancy viability, infant development, sperm; concentration, morphology, motility, volume, DNA fragmentation, chromatin condensation, mitochondrial membrane potential (MMP), and seminal plasma factors. Thirty papers were included, with a total participant number of 115,158. Obese men were more likely to experience infertility (OR = 1.66, 95% CI 1.53-1.79), their rate of live birth per cycle of assisted reproduction technology (ART) was reduced (OR = 0.65, 95% CI 0.44-0.97) and they had a 10% absolute risk increase of pregnancy non-viability. Additionally, obese men had an increased percentage of sperm with low MMP, DNA fragmentation, and abnormal morphology. Clinically significant differences were not found for conventional semen parameters. From these findings it can be concluded that male obesity is associated with reduced reproductive potential. Furthermore, it may be informative to incorporate DNA fragmentation analysis and MMP assessment into semen testing, especially for obese men whose results suggest they should have normal fertility.

Sperm quality and paternal age: effect on blastocyst formation and pregnancy rates

“…Moreover, the combination of BMI and age of both men and women had a negative effect on pregnancy rate. A more recent systematic review with thirty papers included [45] confirm these results. Men obesity does not influence conventional sperm parameters but is associated with reduction of live birth rate per cycle and an increase of DNA fragmentation.…”

An evaluation of comprehensiveness, feasibility and acceptability of a fertility awareness educational tool

“…Since FertiSTAT was published, more rigorous studies of risks and fertilization in men have been performed (e.g. male obesity; Campbell et al, 2015) and it may be possible to generate a valid male FertiSTAT. Testing feasibility and acceptability would also be necessary because perceptions of male fertility and men's quality of life differ across countries (Sexty et al, 2016), including in the Middle East (Inhorn, 2012).…”

Obesity and Reproduction

“…With respect to men, male obesity has been linked to reduced rates of pregnancy and live births (Campbell et al ., 2015). However, studies on specific relationships between semen parameters and obesity have been contradictory.…”

“…However, studies on specific relationships between semen parameters and obesity have been contradictory. Although different studies have shown correlations between increased obesity and changes in sperm parameters, although selectively (MacDonald et al ., 2010, Sermondade et al ., 2013, Campbell et al ., 2015), others did not report adverse effects (Bandel et al ., 2015). On the other hand, recent studies point to a negative association between body weight and the very integrity of sperm DNA (Fariello et al ., 2012; Taha et al ., 2016); however, these results are not unanimous (Bandel et al , 2015; Campbell et al , 2015).…”

“…Although different studies have shown correlations between increased obesity and changes in sperm parameters, although selectively (MacDonald et al ., 2010, Sermondade et al ., 2013, Campbell et al ., 2015), others did not report adverse effects (Bandel et al ., 2015). On the other hand, recent studies point to a negative association between body weight and the very integrity of sperm DNA (Fariello et al ., 2012; Taha et al ., 2016); however, these results are not unanimous (Bandel et al , 2015; Campbell et al , 2015). Spermatogenesis requires a controlled testicular environment and intact endocrine signaling through the hypothalamic-pituitary-testicle axis; and the impact of obesity on fertility can be attributed mainly to the endocrine mechanisms that alter this relationship (MacDonald et al ., 2010; Fariello et al .…”