Secondary infertility is pretty common I'm afraid, and it has it's own challenges for sure. While I feel for those who have not yet had the experience of having their own child, it is definitely a different sort of hardship to have tasted motherhood and then having trouble conceiving.

But at the same time, there are an awful lot of similarities between those who've never had children and those who are trying for their 2nd/3rd/4th whatever, esp when having to look to medical intervention to get you there.