I agree that there are a lot of reasons for Aes Sedai not to want children, most have been touched on earlier. There are two other reasons that would also have a bearing on their decision as well.

The Guide said that the ability to channell is genetic to a degree so it stands to reason that a woman who can channell has a higher chance of giving birth to children who can also channell. What if the child is a boy?

Would an Aes Sedia really want to watch her child grow up for say 20 years and then when he starts to channell watch as he is gentled? What if the child can't channell. Mom will still look like she is in her 20s when he/she is on their death bed dying of old age. Mom will look like 30/40 when her grand children are dying of old age.