Moreover, up to two thirds of maternal deaths occur after delivery. Therefore, the World Health Organization suggests that health care should be provided at 6 hours, 6 days, 6 weeks, and 6 months post delivery, in order to ensure women's physical and mental health and well-being. The postnatal period is defined by the WHO as the period beginning one hour after the delivery of the placenta and continuing until six weeks (42 days) after the birth of an infant. Care during this period is critical for the health and survival of both the mother and the newborn. Globally, it is estimated that more than 500,000 women die of complications of pregnancy and childbirth every year, at least 7 million women who survive childbirth suffer serious health problems and a further 50 million women suffer adverse health consequences after childbirth, the majority of these deaths and complications occur in developing countries.