A study of close to 400 infants found no association between interrupted sleeping and later developmental problems or even mom's mood.

Formula and breast milk encourage the growth of bacteria in babies' guts, just not in the same way. What that means for infant health is unclear.

Imagine a world with twice as many people in it. That's how it would be if fertility rates were the same as in 1970. Choices by women are behind the change.

Understanding why babies born at home versus in a hospital have more diverse microbiota could help prevent disease later in life.

"...it's really important to be able to say to parents, 'your baby's chances have improved, and they've improved significantly,' to give them some hope."