All new mothers experience some sleep loss following childbirth as their oestrogen and progesterone levels plunge, and they typically spend 20% more of the day awake than average during the first six weeks after birth. It is estimated that between 6.5 and 13% of new mothers in the U.S. suffer from postnatal depression and a study of 46 women by researchers at Drexel University in the U.S. looked into the links between sleep problems and postnatal depression. The study found that the mothers suffering from postnatal depression took longer to fall asleep and slept for shorter periods. The worse the women's sleep quality the worse their depression.
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