My LMP (last menstural period) started February 23, 2009. I have PCOS and I don't usually ovulate on my own, but rather with the help of Metformin. This cycle, I took the antibiotic Doxycycline from cycle day 16 to cycle day 26 for a Sinus Infection. Initally, my Basal Body Tempreture Chart indicated that I had ovulated on cycle 16, but a few days later, my temperature plummeted below the coverline and my chart indicated that I hadn't ovulated at all yet.

After a couple of erratic temperatures, my BBT chart is now indicating that I ovulated on cycle day 28 and I have had sustained temperatures for the past 4 days.

I have heard that some antibiotics can delay ovulation and I was wondering if doxycycline was one of them? Even with PCOS I have never ovulated this late in my cycle, I should be getting my period and my temps should be going back down...not up!

Today is cycle day 32 and I am just unsure of what to think.