Abstract: PD13-08
Sources of Funding: AWP is a K12 scholar supported by a Male Reproductive Health Research (MRHR) Career Development Physician-Scientist Award (Grant # HD073917-01) from the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Program.

Introduction

Shift work negatively impacts circadian rhythms and the hypothalamic-pituitary-gonadal (HPG) axis, an integral regulator of spermatogenesis. Here we examine the impact of shift work on semen parameters and reproductive hormones in infertile men._x000D_ _x000D_

Methods

Men presenting with infertility to an academic andrology clinic between January 2014 and October 2016 completed shift work and sleep quality surveys and underwent semen analysis and hormone testing. Men were included in this analysis if unable to achieve a pregnancy within 12 months, and had no known genetic or obstructive causes of infertility. Fertile control men, all having fathered a child within the past 5 years, underwent semen analysis and hormone testing, and also completed the above surveys. Controls prior to starting testosterone therapy (TTh) underwent semen analysis, hormone testing, and completed the same surveys as infertile men. No men in either group had prior TTh use._x000D_ _x000D_

Results

The analysis comprised 198 men: 75 infertile shift workers, 96 infertile non-shift workers, and 27 fertile controls. When comparing shift to non-shift workers, male age, female age, and duration of infertility were not different (Table 1). Sperm density, total motile count (TMC), and testosterone levels were lower in shift workers (p=0.012, 0.019, 0.026, respectively). No differences in semen volume, sperm motility, LH or FSH levels were observed. When comparing infertile shift workers to fertile controls, lower sperm density and TMC, and higher LH and FSH, were observed among shift workers. Semen parameters among infertile men were regressed against sleep quality, sleep quantity, and difficulty sleeping, and an inverse U-shaped trend observed, as previously published [Jensen et al.]. The TMC of men with moderate sleep difficulty was 15.4 M sperm/mL greater than men with no difficulty sleeping, and 4.72 M sperm/mL greater than men with severe sleep difficulty (p=0.018). This inverse U-shaped trend was also observed for sleep quality, but only approached significance._x000D_

Conclusions

Infertile shift workers have worse semen parameters than non-shift workers, consistent with alterations in the HPG axis observed in shift workers. Sleep quality influences TMC, but this relationship follows a U-shaped, rather than linear, trend. _x000D_ _x000D_

Funding

AWP is a K12 scholar supported by a Male Reproductive Health Research (MRHR) Career Development Physician-Scientist Award (Grant # HD073917-01) from the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Program.