Delayed period

[Sara1992]

Hi, I'm currently living abroad, in South America. I'm using a mensual combined contraceptive shot as BC, it is called Mesigyna. I have been using it for almost 9 months without any trouble.
I have irregular periods despite the shot, between 28 and 38 days.
So...the last month I suffered from an UTI and the doctor gave me Macrobid for a week and something like paracetamol. I took the shot in the correct day. I didn't have intercourse during the week I was on Macrobid. The doctor didn't mention any interactions between Macrobid and the shot but now I'm a little bit late...but it's hard to say because of the irregular periods.
I took a pregnancy test at day 39 of my cycle, considering that in the last 6 months my longest period duration was 34 days. It came out negative.
I have cramps and a white discharge that I always have just before my period.

Could the antibiotics and the other medicines mess up my period? Should I test again in a few days? I must have my next shot in 5 days. Thanks.

[Sam W]

Hi sara,

So, if you've taken a pregnancy test according to the directions about when and how to test, you can assume the result was accurate. As for the antibiotics, the person to consult is the doctor who proscribed them or a pharmacist. You can also read more about interactions between medicine and BC here:
http://www.scarleteen.com/article/bodie ... th_control