Question: how come some people can't have babies?

Lilian Hunt answered on 10 Mar 2014:

There are so many reasons why some people can’t have babies. This could be because of something with the father or mother and each can have completely different reasons.

Some common causes are a lack of the monthly release of an egg in the woman, a blockage in the fallopian tubes that the egg has to travel down to get to the womb, and problems with the wall of the womb. In men, the most common cause of infertility is poor quality of semen and sperm.

In around a quarter of cases of people not being able to have babies, the cause is unexplained until further testing can occur. For example, everyone has 23 chromosomes in their egg or sperm cells. These are what the DNA is supercoiled into so it all fits in our cells. Some people can live with bits of their chromosomes flipped round or stuck on the ends of other chromosomes in the same cell and not have it affect them. But when they try and have children, this can cause problems and any embryos made with these errors won’t survive early pregnancy. This is becoming a more commonly diagnosed reason why people can’t have babies, but involves genetic testing and is normally only used if multiple miscarriages happen.