Is Poor Sleep Stopping You From Getting Pregnant?
Research reveals surprising links between female fertility and sleep deprivation
Posted Jun 13, 2019
It’s estimated that 1 in 10 American women have difficulty getting or staying pregnant. When fertility issues arise, couples often focus on the most obvious bedroom activity. But new research suggests sleep, not just sex, may be important when it comes to conceiving.
In an earlier post, I discussed how skimping on sleep impairs men’s sexual health and virility. But as any couple trying to get pregnant knows, it takes two to tango. So today I’ll focus on the impact of sleep deprivation on women’s sexual health and fertility.
Sleep Deprived Women Struggle with Fertility Issues
Why does sleep have such a big impact on female fertility?
The answer is that sleep plays a major role in every stage of the fertility process, from menstruation to conception to birth. This means that at each step, poor sleep can serve as a roadblock.
Poor Sleep Impacts Menstruation
Conducting studies on night shift workers is one of the best ways to see how poor sleep affects people in the real world. And when it comes to female workers doing night shifts, nurses probably have it the worst. Their schedules often involve working all night or regularly shifting between night and day shifts.
Researchers at the University of Washington tracked 68 nurses under the age of 40 and examined their sleep quality. Most of the nurses had sleep issues, some suffering more than others. No surprise there. But researchers also found 53% of these nurses had menstrual changes when their shiftwork started. And these women who did report menstrual irregularities were found to get one hour less sleep a night compared to women who didn’t report menstrual changes.
This data suggests a potential chain of events. Shifting to nights meant these nurses were being exposed to artificial light during the day and sleeping at night, thus altering their natural circadian rhythm. Some nurses handled this disruption better than others. Those who were less tolerant showed disruptions of their sleep, which in turn altered their natural menstrual rhythm.
Poor Sleep Impacts Conception
Sleep deprivation can wreak havoc on women’s (and men’s) hormones. When it comes to getting pregnant, one of the most important female hormones is follicle-stimulating hormone (FSH). When everything is working correctly, FSH reaches its highest point right before ovulation. This is because FSH’s job is to prepare the ovaries for the release of an egg. No FSH, no egg, simple as that. No wonder why FSH is one of the first things doctors test for when fertility issues arise.
Well, it turns out skimping on sleep reduces the amount of FSH that is produced. One study found that women who routinely slept six hours or less a night have 20% less FSH than women who got a full 8 hours. Given how important FSH is in fertility, it is easy to see how skipping just a few hours of sleep a night can quickly spiral into problems conceiving.
Another study brings this point home even more. In it, researchers 656 women currently undergoing in vitro fertilization (IVF) to address ongoing fertility issues. These women’s sleep habits were assessed and they were grouped into three categories: short sleepers (four to six hours a night), moderate sleepers (seven to eight hours), and long sleepers (nine to 11 hours). The results indicated that moderate sleepers had the highest rate of pregnancy (53%). Instead, pregnancy rates among the short sleepers (46%) and long sleepers (43%) were significantly lower.
Keep in mind that IVF is a very lengthy, stressful, and costly procedure. Just a single cycle of IVF can cost $15,000! Chances are good that if these women knew their sleep habits were further impairing their likelihood of getting pregnant, they would've made sure to get the recommended eight hours. But the unfortunate truth is that when fertility issues arise, doctors are more likely to focus on diet and exercise rather than sleep.
Poor Sleep Leads to Pregnancy Complications
Let’s assume a sleep-deprived woman beat the odds and was able to conceive. Even then, her poor sleep habits may still determine if she is able to carry the baby to term. Here are just a few findings linking sleep deprivation with pregnancy complications:
- Pregnant women who do work night shifts or irregular shifts double their odds of miscarriage.
- Pregnant women who work long hours (100+ per week) during their first trimester and experience sleep deprivation, as a result, are twice as likely to have a preterm delivery (10% vs 5%).
- Pregnant women who sleep less than six hours per night experience nine more hours of labor on average than well-rested women (29 hours versus 20 hours).
- Pregnant women who sleep less than six hours per night are four-and-a-half times more likely to have a cesarean birth.
What’s the possible connection here? Doctors don’t know for sure, but one theory with data to back it up suggests that sleep deprivation during pregnancy increases inflammation, which in turn leads to pregnancy complications.
The point is this: Once a woman becomes pregnant, she is not only eating for two, she is sleeping for two. So it’s imperative, for her health and her baby’s, that she get the recommended eight hours every night.
[To learn more about how to improve your sleep, I highly recommend Matthew Walker's book Why We Sleep]