How Old is Too Old To Plan a Pregnancy? [POLL]

My wife's sister commented to her that she is nearing the 'twilight' of her potential child bearing years. I thought I would ask you what your thoughts were on the subject.

There are a lot of factors that can cause problems with pregnancy. Age is, of course, one of them.

Today, 1 in 5 women postpone pregnancy until after the age 35. Still, of pregnant women over 42, many have used assisted fertility technologies and about 50% will not go to full term and give birth.

What do you think?