Must their husbands approve of it, for it to be right?

This kind of mentality is not sound at all and it shows subjugation. A wise man who wants the best for his wife will not allow her to fall pregnant with another child while a two month old infant is still there.

The emotional, physical and mental strain of the first pregnancy is already worthy of note to not make such silly mistakes.

My own is to talk, the wise listen and take heed.