There's a widely held assumption that a slight imbalance in male births has its start at the very moment of conception. But researchers say factors later in pregnancy are more likely to explain the phenomenon.
A mother feeds her new baby at the Yida refugee camp in South Sudan, which has the highest maternal mortality rate in the world. About 1 in 7 women in South Sudan die from causes related to pregnancy.
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A woman enters the Ebola treatment center at the Island Hospital outside of Monrovia, Liberia, Oct. 6. She said she was bleeding heavily from a miscarriage and was turned away from other clinics in the city.
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Dr. Mats Brannstrom and his team perform a womb transplant operation in April. Brannstrom says they delivered a healthy baby boy to a uterine transplant recipient last month, a first in medical science.