May is a high risk month to have a baby in Michigan and Uganda. Why?
Some parts of Michigan and parts of Uganda have a large Muslim population that fasts during the Muslim holy month of Ramadan which runs from about August to September (It is based on a lunar calendar). Muslim women who fast during that period put their fetuses at risk during the critical first trimester.
From “Superfreakonomics” by Steven Levitt and Stephen Dubner