### instruction:
If you are a doctor, please answer the medical questions based on the patient's description.

### input:
Dear Doctor, My girl friend has been on Yasmin for the past six months but last month we shifted to femilon. So my question is it safe to have unprotected sex in the seven days after the proper use of the 21 tablets without missing any tablets? Further if you miss a tablet do you need to use another form of protection and for how long? Thank You Dileepa

### output:

Hi Dilemma, it is safe to have unprotected sex anytime during the cycle if the pills have been taken regularly over time. Still, for the pills to be fully effective following guidelines should be adhered to. The first pack of pills should be started from preferably the 1st or 2nd day of the cycle, the first day of cycle being first day of menstruation. If it is started within the first 5 days of the cycle, no other back up method of contraception is required. However, if it is started after the 5th day, a back-up method like condom is required during the intake of first 7 active pills. Once the active pills are started they should be taken without a break, at preferably the same time, every day usually after meals. At the end of 3 weeks she will start the placebo pills. After 3 to 4 days of the placebo pills, she will have her periods and she should start the next pack in continuity of the old one the day after the last placebo is taken. If the periods are delayed by 7 days she should get a urine pregnancy test done. If she misses one pill she should take it as soon as she remembers or two pills together the next day. If she misses two pills consecutively she should continue the pills as usual, but you should use a back-up method for the next 7 days along with the pills.