I Am Supposed To Have The Prostap Injection On June

I am supposed to have the prostap injection on June 29th, in preparation for IVF cycle. My husband and had intercourse a couple of days ago and now I'm worried that there is the smallest chance that I may become pregnant naturally and this would be dangerous for the baby. I have unexplained fertility, have fallen pregnant naturally once but it ended in miscarriage but have not had any other natural pregnancies during 10 years of marriage, so the likelihood of falling pregnant is low, but I wouldn't want to endanger a baby. Is it safe to proceed with treatment?