If you have the birth control implant, then you are already on a good contraceptive method and your chances of getting pregnant are highly unlikely. But by the same token, no birth control method is 100%. But to answer your question again, for two reasons, you are highly unlikely to get pregnant: 1-you started your period, and 2- you are using contraception with the arm implant.

Once you start your period, you cannot be pregnant.
The egg only lasts for about 24 hours and that is usually in the middle of your periods. If you have a cycle that comes every 28 days, you will ovulate around day 14. If you have sex between days 10 and 18, sperm can last for up to 3 days and therefore could still be alive when you ovulate. How to prevent pregnancy?
1. ABSTAIN-no sex,
2. Use some form of birth control including condoms.

If you have implant, it is very unlikely that you will get pregnant. If you are sexually active, see a gynecologist regularly.

Best,

Dr. Anjan Chaudhury

Good morning,

I would urge you to see a physician for back up birth control and use condoms to prevent sexually transmitted diseases and prevent pregnancy. If the bleeding truly was your period, then this is not a time pregnancy can occur. Protect yourself and use condoms.

Michelle Harden, MD FACOG