Does lifting weights cause complications in child birth later on?

I don't see why it would as long as you aren't currently pregnant. In fact being in good physical condition is great for childbirth. But check with your doctor.

Lifting weights actually increase your bone density. When you are pregnant, the fetus can leach calcium out of your bones if you aren't eating enough. Stronger bones means better support for baby, both by supporting it's weight, and for avoiding depleted bones. So, weight lifting before you are pregnant is very good for you and your future pregnancy.

I am of the understanding that it doesnt if you arent being to strenuous in your workouts

I don't think so.

I think you should not lift weights after you know you are pregnant. It is better to be safer than sorry. What do you say? I would hate to take any chance and then realize complicaitons in delivery happened because I was over zealous in body building.