If your girlfriend is using the patch correctly, you should be fine. She needs to wear the patch for three weeks straight (a new patch each week) and then leave the patch off for a week. If she put on a new patch on the 17th and the sex occurred on the 21st, you needn’t worry too much about pregnancy. She just needs to remember her next patch on the 24th. Of course, no birth control method is 100% effective, but the patch is 99% effective when used correctly.
23. February 2012
anonymous-qa