Expert: Norman Solberg - 12/21/2008

Question
I have been on the pill for about two years now. I started out taking Trinordiol, which are 21-day pills, but they were really hard to find at the pharmacy. So I decided to switch to Ovral 21, which are also 21-day pills. I was on Ovral 21 for about a year and a half and this last time I had a hard time finding them, so the pharmacist recommended I take Mia, 28-day pills. She said there was no problem with switching and that I could start taking them on the day I would've started the Ovral 21. According to the instructions I was supposed to wait 7 days after I started the pills to have sex, but I had unprotected sex after day 4. What is my risk of getting pregnant after having done this? Is it safe to switch pills this way or should I have done something different? Help! I'm really very concerned.

Answer
Hi Barbara,
It is safe to switch from one birth control pill to another.  Usually the differences are small and you can continue the new one just like your old one.  I believe the only time you might need to wait 7 days to have sex is if the new pill had a lot lower hormones than the old one.  I am not familiar with Mia and not able to find it.  I assume it's one of the newer generics.  Since the pharmacist recommended it, it's probably similar to Ovral, in which case your chance of getting pregnant is very slight.