Well there are some kinds of diseases those are genetic spread generation by generation. Therefore during pregnancy and after having baby new mothers are worried about their baby's health issues. Here also we have witness how mental condition transfer family generation to generation and also it affect the new born babies; so we need to understand the entire situation and trying our best to skip these kinds of problems.
http://www.babysteals.com.au/blog/ready-for-a-baby-a-few-things-to-consider-before-taking-the-plunge