Pregnant?

[http://users.livejournal.com/--fourinchesx/]

History:
I'm on Gildess/Microgestrin, as a side note. About three weeks ago, I thought I had a YI, so I decided to go to the doctor. She did a swab for any other infections, but said it looked like a YI and prescribed the YI pill-thing. That was a Friday. That next Monday I got a call about my swab results and they said I had BV, which is whatever, and that they prescribed me Flagyl. I filled the prescription and went about my business. No sex for a week, due to the antibiotic, and everything was feeling better after the seven days.

Fast forward:
I had sex after being off the antibiotics, but only waited two days, which as I now know isn't long enough to wait after taking antibiotics on your BC. The end of my pack fell on June 6th (of the 28 day pack), which was this past Monday, and I was supposed to start my period on the 8th/9th. It didn't come. I waited until Saturday, just to be sure it wasn't going to spring up on me a little late, and it never came. I took a pregnancy test and it was negative. I guess my questions are:

1. Was it too early to take a pregnancy test and expect accurate results?
2. Could the antibiotic have affected my cycle?
3. How long are you really supposed to wait to have sex after being on antibiotics with BC?

I'm just freaking out, I'm hoping. :(

Comments

[archangelbeth]

A question: did you wait longer than 7 days before resuming your HBC? If so, your protection was compromised (to an unknown degree) until you took 7 days of active pills. (If it was 7 days or fewer, then that's okay.) I'm really bad at counting dates without touching a calendar, so I just wanted to be sure.

As for the rest, "what kimie_catclaw said." O:>

I hope you feel better soon! If you feel you need to take more tests, and are in the US, peeonastick.com likes Dollar Tree Store tests.


(Citations:
http://www.ncbi.nlm.nih.gov/pubmed/12436822 (a 2002 report)
"To date, all clinical trials studying the effects of concomitant antibiotic therapy (with the exception of rifampin and rifabutin) have failed to demonstrate an interaction. [...] On the other hand, if the interaction does exist but is a relatively rare event, occurring in, say, 1 in 5000 women, clinical studies such as those described in this article would not detect the interaction. [...] the incidence of such a rare interaction would not differ from the accepted normal failure rate of oral contraceptive therapy. [...] Though experts on this topic still recommend informing oral contraceptive users of the potential for a rare interaction, and for clinicians to advise them to employ additional barrier techniques of birth control during antibiotic therapy and for at least 1 week beyond the last dose [40], it is hoped that a set of guidelines regarding this controversy will eventually be published that is evidence-based, and not solely the results of anecdotal reports, expert opinions, and legal proceedings."

http://www.ncbi.nlm.nih.gov/pubmed/11704183 (a 2001 report)
"Apparent OC failure rates in clinical surveys were within the usual range expected for patterns of typical use. In pooled results obtained from relatively small populations, oral antibiotics, with the exception of rifampin, have not significantly affected the pharmacokinetics of ethinyl estradiol, levonorgestrel, and norethindrone or reduced the serum concentrations of gonadotropins. However, individual patients have been identified who experienced significant decreases in the plasma concentration of these components of OCs and who appeared to ovulate. [...] Because it is not possible to identify these women in advance, a cautious approach is advised."

http://www.ncbi.nlm.nih.gov/pubmed/12063491 (2002 report) pretty much duplicates the above ones.

Also, http://www.mayoclinic.com/health/birth-control-pill/WO00098/NSECTIONGROUP=2 -- "The effects of antibiotics on birth control pills may be overstated — except in the case of one antibiotic, rifampin (Rimactane). Studies clearly show that rifampin decreases the effectiveness of birth control pills in preventing ovulation. However, rifampin isn't used widely today." )