Hitting the Gym

Hello! I am 10 weeks postpartum and wanted to get into weight lifting before I found out I was pregnant. I feel ready to hit the gym, but I’m wondering how I should pace myself when it comes to weight lifting? What should I start out at? (I could lift almost 200 pounds before I got pregnant with some ease) My OB restricted me to 50 pounds in my third trimester, so I’m wondering if I should start out with 50 pounds or if I’m safe to go straight for 100 to start?