Is it possible to be pregnant and not know it?

Imagine not knowing you're pregnant until you go into labour. For many women that seems impossible, but it's a rare phenomenon that does happen.  These types of pregnancies are referred to as hidden, concealed or cryptic pregnancies. Hannah Dahlen is a Professor of Midwifery at Western Sydney University. She attended a labour of a hidden pregnancy, and talks about how women can go through nine months without knowing they are pregnant.See omnystudio.com/listener for privacy information.