Withdrawal method

Is withdrawal still effective with multiple rounds...? I read somewhere that Precum after a round has more sperm in it and withdrawal is less effective. Any insight on this?

My fwb and I had a few rounds with withdrawal method, I am not on birth control, and my period is 2 days late. Only 2 days, so I’m not too worried yet. But I’ve also been so tired the past couple of days. I slept until 4pm yesterday. Went back to sleep around 11pm, woke up at 9am, and I’m 100% about to take another nap.

Let me know!