Two interesting studies have been conducted regarding the impact of night work (night shifts) on women’s health.

• The results of the first study were published in Occup Environ Med 2019 and looked at the impact of night shifts on early pregnancy loss. It turned out that the number of miscarriages was higher in those women who had at least two-night shifts compared to those who had no night shifts. After adjusting for age, weight, smoking, previous pregnancies and deliveries, two or more-night shifts per week between 8 and 22 weeks of gestation increased the risk of pregnancy loss by 32%. In women who have 26 night shifts from weeks 4 to 22, the risk of pregnancy loss is increased by 2 times.

• The second study focused on the topic of menopause depending on night work. The results are published in Hum Reprod. 2019;34(3):539-548 Does working night shifts affect menopause?

The study followed almost 81,000 women during 1991-2013.  in 34% of women menopause occurred naturally in accordance with age. Women who worked 20 months or more in shift work (night and day shifts) had an increased risk of having menopause 2 years earlier than those who worked daytime. This risk was higher for women younger than 45 years of age. Also, in younger women, the risk of early menopause increased with 10 years of shift work. The relative level of risk was determined. The mechanism by which the risk increases is not yet clear.

Melatonin, which may play a role in animal reproduction, does not affect human reproduction. Such changes are explained by an increased level of stress and a violation of the circadian rhythm, which can also lead to impaired ovulation. The production of gonadotropins (LH and FSH) depends on the circadian rhythm, which I wrote about in my book on hormones.

Don’t forget about ♥️