The only way someone can know if they are pregnant is to take a test at least 14 days after the most recent sexual contact. The result can be trusted at this time.
Being on a form of birth control, like the Nexplanon will not affect the accuracy of a pregnancy test.
Remember, if someone has been on the Nexplanon for at least a week they are 99% protected from pregnancy for 3 years. Hormonal forms of birth control like the Nexplanon do not protect against STIs. Only condoms and dental dams can do this!
If you have any more questions, give our Teen Clinic a call at 303-442-5160