This week, I had the opportunity to discuss the findings of a recent study presented at the annual American Society of Reproductive Medicine (ASRM) meeting in Boston.

A team of South Korean researchers presented their findings on the sleep habits (self-reported) of 656 women prior to starting IVF treatment. Pregnancy rates were highest (52.6%) among moderate-time sleepers (7-8 hours).  Women who sleep 9-11 hours exhibited the lowest pregnancy rate at 42.9%.

While this study’s findings are certainly interesting and the first to report, they clearly do not establish cause and effect between sleep duration and successful IVF.

The link between a good night’s sleep and fertility

This study got me thinking, what do we really know about sleep and fertility? The answer is not much.

The amount that each individual needs for optimal health varies. It is generally thought that adults require 7-9 hours of sleep daily. The quality of sleep is equally important.

Sleep disorders are common. According to the CDC, about 70 million Americans suffer from a chronic sleep problem. In the 1998 Women and Sleep poll, the National Sleep Foundation (NSF) found that woman aged 30-60 slept an average of six hours and forty-one minutes during the workweek. In 2005, the NSF Sleep in America study reported that women are more likely than men to have difficulty falling and staying asleep. Sleep disorders can be primary, or due to a number of different medical conditions.

Poor sleep habits have been associated with increased risks for infection, obesity, diabetes, cardiovascular disease, depression and cancer. Too much or too little sleep may disrupt our circadian rhythm. Such disruptions may alter reproductive hormone secretion.

There is currently little research looking at sleep and fertility. In a 1998 study, Nurminen observed that women who work at night are more likely to have trouble conceiving or to miscarry. A 2012 report from Europe found that women who did shift work had a great incidence of menstrual abnormalities, miscarriage and a greater frequency of infertility. Not all studies have reported this association. The available research looks primarily at sleep quantity, not quality or co-founding factors that may influence sleep. In men, there is no clear evidence between a reduction of fertility and working night and/or long shifts.

We must remember that a number of factors can affect sleep. Patients with sleep disorders may have other medical issues that can influence fertility such as obesity, sleep apnea, seasonal affective disorder and depression, as well as taking medications that can alter sleep and hormone regulation.

My recommendations:

1. Adults should obtain 7-9 hours of sleep daily.

2. Be consistent in your sleep habits.

3. If you are having sleep issues, discuss with your healthcare provider.