Causes of miscarriage r many and peculiar to an individual as Dr Ayo outlined. Whn someone miscarries, ur dr wil examine u, and know d exact cause to avoid reoccurrence. But some r genetics or unexplained.
@Nwachyyy, yes, if the sperm is not healthy/matured the baby wouldn't stay. There's something that soft drinks contains that's not good for early pregnancy. Too much of paracetamol causes miscarriage too.