Zoloft may have been suggested because it's an older one and there is more data. Although, no medication is totally safe during pregnancy the benefits may outweigh the risk. I take welbutrin sr 150 mg once a day and I'm 17 weeks with twins. It's noted as a safer one since it's one of the oldest antidepressants on the market. It's a personal decision do your research and trust your gut.
I was on Zoloft before I got pregnant but many of my doctors told me to quit taking it before I tried due to it not being good during pregnancy.
Im on 50mg zoloft every morning. Before going on it i got opinions from my ob, a perinatal specialist and a pediatrician. All agreed it was in mine and babys best intrest. I started on it at 15wks, i am 36+ now and will continue to take it after birth and while breastfeeding.