What are the causes of misconception?

Reproductive or Mind: I can't tell if you mean to ask about conceiving a baby or about incorrect ideas about things. Difficulty conceiving can be from problems of many sorts in either partner. Both need to be examined and counseled. The cognitive sort also come from a wide range of causes - internal and/or external. Ask again more clearly if you wish. Best!

Miscarriages: are both very common and many times occur without the woman even know she was pregnant.