irregular length between periods?

Question

My girlfriend hasn't had her period for almost six weeks (since the start of her last period.) We have been practising safe sex since then with a condom and I know that there is a small chance of still getting pregnant but do you think i should be worried? She has had an irregular period before and her last period she took Plan B. Could this have something to do with the length inbetween periods?
Please don't respond to this if you are going to say something ignorrant like "you should have chose abstinance"- this is yahoo answers not yahoo time machine. thanks

Answer 1

The female menstrual cycle naturally varies. It isn't always exactly the same length, and generally when it is, there isn't anything "wrong" or "weird" about it. Mine has varied between 29 and 38 days... however, I chart my cycles so I know that they are, actually very "regular."
Plan B, however, is a basically just a large dosage of the Pill, and can, therefore, cause some irregularities in a woman's cycle. I wouldn't worry about it too much. Just remember, no birth control works 100% of the time; if you aren't prepared for the possibility of pregnancy, don't have sex.

Answer 2

My ex had reallllyyy irregular periods too. The best advice I can give is get an appointment made with a Gynecologist (OBGYN) and have her examined. They can not only tell you if she is pregnant or not but likely what the cause of her irregular cycles are and what can be done to regulate them -- if anything can be done.

-- Jazz