Taking antidepressants while pregnant?

Meg • Baby Boy coming 3/2/2016
I have been on Prozac for several years and I went off it when we started TTC. My doctor said if I felt like I needed to go back on them during and/or after my pregnancy that it would be ok. I am incredibly hesitant to do so and I was wondering if anyone had any experience taking them while pregnant or breastfeeding?