Should I consider my birth control as failed?

[FactoryGirl22]

Hi there, I am a 22 year old with a question regarding hormonal birth control and whether or not I should be concerned that it, and backup measures, may have failed. I am currently taking a combined pill (Yasmin) and have been on the pill for over 5 years. It was originally prescribed for acne control, but I have recently become sexually active as well. I am currently on my third consecutive pack of hormone pills, having skipped my previous two placebo weeks/withdrawal periods. This has been approved by my prescribing doctor, however this is the first time I have skipped two periods in a row. I would describe myself as a typical user, however within two months of becoming sexually active I have been more stringent with my routine and have only missed one pill by more than 12 hours, and I doubled my dose as soon as I remembered. My concern is regarding a prescription for an antibiotic (Doxycyline) that I took for a week while taking birth control. I have been told that only certain antibiotics decrease the effectiveness of hormonal birth control and on the online drug information page for Yasmin, Doxycycline is not listed as a possible drug interaction. However, the label of my antibiotic states that it may effect hormonal birth control. I am not sure which information to follow. My boyfriend and I use either condoms or withdrawal as secondary birth control measures, but I believe on a couple occasions we were not 100% successful with withdrawal (possible pre-ejaculate, and ejaculate near or on vulva) and I believe this may have happened while I was taking both the antibiotic and birth control. I am currently two hormone pills away from the placebo pills on my third consecutive pack of birth control and intend to take the placebo pills. Previously this month I noticed bladder inconstancy, but it was not continuous. I have noticed last night and today a light reddish tinge on toilet paper after urination and a small amount of brown discharge on two occasions, as well as gas and a bit of bloating. These have not occurred prior to withdrawal bleeds for me before. Should I be concerned that this is possibly implantation bleeding, or could it be PMS symptoms that may be a result of skipping two withdrawal bleeds already? Should I consider both my primary and secondary measure of birth control as failed? Should I take a pregnancy test now, or wait and see if I do have a withdrawal bleed? Should I still take a pregnancy test if I do have a withdrawal bleed? My boyfriend and I are both STI free, and I intend to suggest we stick to condoms as our secondary measure of birth control from here on, as I am more comfortable with that level of protection.

[Karyn]

Even if your antibiotic did affect your birth control, it would not have made it completely ineffective - you would still have had some protection from it. Given that you did use a backup method (albeit not perfectly) as well, I'd say your risk of pregnancy is still fairly low, but your doctor or pharmacist would be the best person to double check with about that. They're also the people to ask any time you're unsure about medication interactions, too.

Implantation bleeding is fairly uncommon, so even if you had become pregnant, it's more likely that what you would notice is a total lack of bleeding. If this is the first time you've skipped more than one placebo week, and you've been ill (which can affect your cycle even when you're on the pill) it wouldn't be at all unusual to have some breakthrough bleeding, and it's entirely possible that's what's going on here. However, you have had a risk of pregnancy, so taking a test would be a good idea. If enough time has passed since your possible risks, you can go ahead and do that now, or you can wait and see if your withdrawal bleed shows up and test if it doesn't; it's up to you.