Need to Know Gender

Hey Ladies, so me and my husband want to wait to find out the gender until birth (my desire not his but he's going along with it) and I am really struggling more than I thought with the unknown. I've read all the old wives tales and I fall into none of the categories so now I'm trying to figure out the placenta placement gender reveal. At our 20 week ultrasound the placenta was on the left of the screen. does that mean placenta would be on the left?? has anyone used this as a way to determine gender??