You don't say which women you mean - body builders? Fitness? or just general gym rats?
I think one of the best long term health effects is warding off osteoperosis - that's why after 35 I believe women need resisitance training more than men do.
I can't answer the fertility question 'cause I don't have kids, but why would body building interfere - if anything it would make chlidbirth (natural) all that easier. This I can attest to as friends have had chidlern and lifted. One lifted into her fifth month!