It may be sexist, but unfortunately, men have longer biological clock, and they age better.
Once a woman turns 30+, her options becomes limited. There aren't that many men around in their mid-thirties who may be considered 'good catches' and are not already married.
If a woman can not find 'mr perfect' when she is in her prime, how likely is it that she would be able to find him when she is past her prime?
Having a child makes thing more complicated. I know several women that I like, but I am not willing to live with the complications of their children: being father figure to a child who already has a biological father, visitations, etc.