Study Says More Sun Exposure During 3rd Trimester Could Help Prevent Postpartum Depression

"Women should be encouraged to get frequent exposure to daylight throughout their pregnancies ..."

While it's no secret that the darker days of autumn and winter have long since been correlated with Seasonal Affective Disorder (SAD), a study suggests that decreased sun exposure might also increase the likelihood of postpartum depression in women.

Published in Springer's Journal of Behavioral Medicine, the report claims that a lack of sunlight during the third trimester boosts a woman's chances of experiencing postnatal depression. According to the report, women who are in the late stages of pregnancy during the darker months of the year may have a greater risk of developing postpartum depression once their babies are born.

Led by Deepika Goyal of San José State University and her colleagues at the University of California San Francisco, researchers analyzed 293 first-time moms as part of a controlled experiment about sleep before and after pregnancy. The women shared the amount of daylight they enjoyed during the final trimester of their pregnancy, as well as information about known risk factors, such as a history of depression, age, and socioeconomic status.

Overall, participants had a 30 percent risk of depression, suggesting that the number of daylight hours a woman was exposed to during her final month of pregnancy and just after birth had a major influence on the likelihood that she developed depressive symptoms.

"Among first-time mothers, the length of day in the third trimester, specifically day lengths that are shortening compared to day lengths that are short, long or lengthening, were associated with concurrent depressive symptom severity," Goyal explained as part of the official report.


Tired mom with baby. 
globalmoments / Shutterstock

As anticipated, women whose final trimester coincided with longer daylight hours had the lowest risk for depression (26 percent), while women whose third trimester occurred during "shorter" days had the highest risk of depression (35 percent), with symptoms becoming more prevalent following the birth of her baby.

Goyal notes that the findings suggest using light treatment late in a woman's third trimester during these shortened days could minimize postpartum depressive symptoms in high-risk mothers during the first three months of their children's lives. Goyal says that women with a history of mental health problems, and those who are already experiencing depressive symptoms in the third trimester. might benefit from being outdoors, in particular, or using devices such as light boxes that provide light therapy.

"Women should be encouraged to get frequent exposure to daylight throughout their pregnancies to enhance their vitamin D levels and to suppress the hormone melatonin," Goyal added. "Daily walks during daylight hours may be more effective in improving mood than walking inside a shopping mall or using a treadmill in a gym. Likewise, early morning or late evening walks may be relaxing but would be less effective in increasing vitamin D exposure or suppressing melatonin."

Thus, mothers who expect to give birth during the fall or winter can actively work to minimize or prevent these symptoms by incorporating more vitamin D into their diet. From supplements, to good old-fashioned sunshine, this natural mood booster can also help relieve postpartum depression before the symptoms emerge or overwhelm.

Cover image via Tapao / Shutterstock

(H/T: The Bump)


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