Could Your Job Be Affecting Your Fertility?
Could aspects of your job be affecting your fertility? A new study published in the BMJ Journals in Occupational and Environmental Medicine in February 2017 shows that there may be a link between a woman’s work-life and her fertility. They explored whether overnight work schedules or high physical demand were associated with a decline in ovarian reserve and responsiveness to IVF medications.
They found that women who performed heavy lifting at work had 8.8% fewer total eggs and 14.1% fewer mature eggs compared with women who performed less manual jobs. A similar trend was seen in women who worked overnight shifts. Since the study did not include a link between occupational factors and estrogen or FSH hormone levels, what can be concluded about how these work stresses are affecting our fertility?
Scientists are concluding that working the night shift can interrupt our natural circadian rhythm. This is responsible for regulating hormones, including those involved in fertility. A study published in Molecular and Cellular Endocrinology in 2012 discusses the role of circadian rhythms in regulating ovulation, estrogen, implantation, and the maintenance of pregnancy. The ovaries have a cellular rhythm, and disruption of the “clock gene function” can reduce fertility. The stress of the abnormal sleep patterns make hormones like cortisol and prolactin to run at abnormal levels.
Intense exercise has been linked to hormonal stress leading to amenorrhea in female athletes and other disorders such as delayed or irregular periods, problems ovulating, inadequate luteal phase, and secondary amenorrhea. Many of the involved with stress response and reproductive functions are also present in the placenta, which may affect pregnancy.
Since this is one of the first studies linking a woman’s work-life to her fertility, there are other many more questions that need to be answered. Do estrogen or FSH hormone levels change with the work environment? Would changing to a day-time work schedule or reducing the physical work-load normalize the antral follicle count and increase the number of mature eggs obtained through fertility treatment?
http://oem.bmj.com/content/early/2017/01/04/oemed-2016-103953 http://www.sciencedirect.com/science/article/pii/S0303720711004953 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1519933/pdf/envhper00379-0064.pdf