Early 30s is just fine for child bearing, as probably the majority of women have their first in late 20s and more are pushing that age into their 30s. 40/early 40s is where for most women you can actually begin to measure fertility decreasing on a monthly basis, and late 30s is where the biological clock goes into overdrive. I'm in my late 30s, and trying to fine someone my age not interested in having children is a nightmare. Basically, this is the last boat for those single women who want a family but failed to account for aging.