A woman’s ability to conceive may be negatively affected by physically demanding jobs, and work schedules outside standard office hours.
According to research published online in Occupational & Environmental Medicine, evening, night, rotating shift hours, and heavy lifting were correlated with reduced egg quality.
To study this issue, investigators looked at the ovarian reserve in 473 women attending a fertility clinic, and at the ovarian response of 313 women who finished at least one IVF (In Vitro Fertilization) cycle. The average age of the women was 35.
Ovarian reserve includes the number of a woman’s remaining eggs, and her level of FSH, or follicle stimulating hormone. FSH rises with age, and indicates declining fertility. Ovarian response is the number of eggs that are mature, and able to grow into healthy embryos.
The researchers found that the type of workload a woman engaged in did not affect FSH levels; however, those with physically demanding jobs had a smaller reserve of eggs compared to those who did not do heavy lifting. Also, those with physically demanding jobs who were undergoing IVF had lower total reserves of eggs, and fewer mature eggs. The diminishment of egg reserves was more pronounced in women working evening, night, and rotating shifts.
“These findings have clinical implications, as women with fewer mature oocytes would have fewer eggs which are capable of developing into healthy embryos,” write the investigators. Moreover, the results “suggest that occupational factors may be more specifically affecting oocyte production and quality, rather than accelerating ovarian aging.”
Since this was an observational study, no definitive cause and effect conclusions can be made. Factors such as switching between day and night shifts, and long working hours were not addressed in this project. The researchers also point out their findings may not apply to couples who are trying to conceive without medical assistance.
Still, the outcomes of this investigation are in line with similar studies. “Taken together with our results, it appears that lower oocyte quality could be one pathway mediating the relationship between high frequency of moving or lifting heavy loads at work, and reduced fecundity,” note the researchers.
Source: Science Daily
photo credit: photoskate