I've been on birth control but i don't take it as i should miss 3 pills in a row and had unprotected sex could i be pregnant?

Yes: if you miss your period, you should do a home pregnancy test. You should also consider whether the birth control pill is the best form of contraception for you. If you are not able to take it reliably, it is risky. These days, there are other methods of contraception which are more reliable than the pills, if they are not taken regularly. You should discuss this with your gynecologist. Good luck.

Yes: As with all medications, they only work when taken as directed. By missing even a single birth control pill, you increase your chances of pregnancy if engaging in sex w/o any other form of contraception. After missing 3 pills, that's equivalent to no contraception whatsoever. Of course, this assumes you're referring to active pills, not last week of sugar/placebo pills. Check http://goo.gl/bN7hzP

Possible: Breakthrough ovulation and pregnancy are possible during cycles with missed birth control pills.

Yes, you could be: ."Missing 3 contraceptive pills in a row" may cause the level of hormones in your blood to drop in such a way that you ovulate and therefore increase your risk of getting pregnant. You will greatly benefit from switching to the most effective, "forgettable" ways to prevent pregnancy which are an IUD or a subdermal implant (plus condoms for STI protection) Be safe. Consult your gynecologist soon