研究發現 產後抑鬱或與孕晚期日照不足有關

A just-published study has found an interesting association between pregnant womens' exposure to natural daylight and their susceptibility to postnatal depression (PND).
一份最新研究發現，孕期自然光照多少與她們患產後抑鬱（PND）的機率之間存在着有趣的聯繫。

"Women in late pregnancy during darker months of the year may have a greater risk of developing postpartum depression once their babies are born," Science Daily reports.
據《每日科學》網站報道，孕晚期處於一年中光照較少月份的女性，在嬰兒出生後患產後抑鬱的風險較大。

"This is consistent with what is known about the relationship between exposure to natural light and depression among adults in the general population."
“這與自然光照多少與一般人羣中成年人患抑鬱機率大小之間的已知聯繫相符。”

Dr Deepika Goyal of San José State University was lead author on the study, which was just published in the Journal of Behavioral Medicine.
該研究發表在英國《行爲醫學雜誌》上，主要作者是美國州立聖何塞大學的迪皮卡·戈亞爾。

Dr Goyal and her team looked at 293 Californian first-time mums, analysing the amount of daylight they were exposed to during the final trimester of their pregnancy. They also looked at each woman's history of depression, her age, her socioeconomic status and how much she slept.
戈亞爾博士和她的團隊觀察了加州293名初產產婦，分析了她們在懷孕最後三個月接受光照的時間。此外，他們還研究了每位女性的抑鬱史、年齡、社會經濟地位以及睡眠時長。

They found that the lowest risk for depression (26 percent) was seen in women whose final trimester coincided with seasons with longer daylight hours.
他們發現，患抑鬱症風險最低（26%）的女性，她們的孕晚期時間正是白晝時間較長的季節。

The depression risk was highest (35 percent) in women whose final trimester coincided with days with fewer daylight hours. These womens' depression-related symptoms were more severe following the birth of their babies.
患抑鬱症的風險最高（35%）的女性，孕晚期時間正是白晝時間較短的季節。這些女性的抑鬱相關症狀在產後更加嚴重。

The findings have lead to some specific recommendations for women who are prone to depression or are due to deliver in months when the daylight hours are fewer (like Winter).
這一發現爲那些容易抑鬱或是將要在日照較少的季節裏（比如冬天）分娩的女性提供了一些具體的建議。

"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," Dr Goyal said.
戈亞爾博士表示：“應鼓勵高風險孕婦多接受自然光照以及攝入維生素D，並抑制褪黑激素。”