From the hormonal fluctuations of early pregnancy to the kicking fetus of the later stages to the late-night demands of newborns, lack of sleep goes hand-in-hand with parenthood. In fact, 75 percent of pregnant women report some sleep disruption—and experts believe that number may be low.

But while a certain amount of fatigue comes with the territory, sleep disturbance is also linked to depression. And the two conditions can be a crisis combination for women during and after pregnancy. In an on-going interdisciplinary study led by third-year clinical psychology doctoral candidate Sammy S. Dhaliwal, a clearer picture is emerging of the role of sleep disturbances and its link to depression during the often-overlooked perinatal period that encompasses pregnancy and continues through the first 12 months postpartum. Dhaliwal is working with a 25-member team that includes psychology faculty advisers and fellow graduate students, GW medical students, researchers from Children's National Medical Center in Washington, D.C., and technology consultants from Apple and Deloitte. Dhaliwal recently received a $33,500 grant from the National Institutes of Health to see the research to its completion.

“The results from this project will provide the field with new and important knowledge about sleep, an understudied but necessary research endeavor to inform existing interventions for perinatal women,” said Associate Professor of Psychology Huynh-Nhu (Mimi) Le, Dhaliwal’s primary faculty advisor.

As many as one-in-five new mothers experience some degree of postpartum depression, from appetite shifts and low energy to thoughts of harming themselves or their babies. The numbers are likely similar for women throughout their pregnancies, Dhaliwal suggests, but there’s little current research covering pregnancy through postpartum. That’s a significant hole, she notes, since the single largest predictor of postpartum depression is depression during pregnancy. “If you become newly depressed during pregnancy, you are almost guaranteed to become or to remain depressed in the postpartum period if untreated,” she said. And while the American College of Obstetricians and Gynecologists recommends that OB-GYNs screen patients at least once during the perinatal period for depression, there is little emphasis on sleep disruption, Dhaliwal said.

“Postpartum, women have their sleep disturbed by things like crying babies or getting up to breastfeed. We all recognize that. But we have to understand that it also can be hard to sleep with a baby growing inside you. We need better tools for assessing [sleep disruptions in] both periods,” she said.

Two Way Street

The “bi-directional” relationship between sleep and depression is a “two-way street," Dhaliwal explained, with sleep deprivation serving as both a symptom and a risk-factor for depression. Her research set out to explore whether the sleep disruption she expected to see from pregnant and postpartum women contributed to new onsets of depression.

Dhaliwal’s team is in the process of recruiting 50 women without a history of depression or sleep disorders from the Obstetrics and Gynecology Division at the George Washington University Hospital System. The researchers are following the participants through a 10-day, nine-night protocol, from pregnancy (third trimester, week 28) through postpartum (week 6). Using a daily diary phone app, the team can track how and when sleep impacts mood among pregnant and postpartum women, with a focus on negative daily stress appraisals. The key to the study, Dhaliwal says, is a “within-person” design that compares each woman’s unique sleep characteristics from pregnancy to postpartum. “We don’t compare separate groups of women. We compare one woman’s worst day to her best day. And we do it during her pregnancy and then again postpartum.”

The study, which is scheduled to conclude in the spring, may have significant implications for mothers and their entire families, Dhaliwal said, noting that perinatal depression has been linked to detrimental outcomes from low birth weight to poor scholastic achievement to childhood depression. “Depression during pregnancy or postpartum affects not just the mom but the baby too,” she said. “It has the potential to change the trajectory of a child's life.”