Hi hon. For me my last shot was April. I got my first period in October and was pregnant then in November. I was on the shot for almost 4 years. My doctor told me it takes 3 months for the shot to get out. Which I guess that is correct. I was suppose to get my shot in July but I wanted to get pregnant. So I stopped in April and then in October cycle came back but I had my period for 16 days. Next normal period was November and I got pregnant that month. Good luck Sherri