low BBT or not?

iVillage Member
Registered: 11-08-2005
low BBT or not?
Sat, 03-16-2013 - 2:07pm

I am worried that my temperature will never be high enough to sustain a pregnancy.

I'm BBT charting and "everyone" says average luteal phase temp should range between 97.2-97.7, then after O, it should be 97.6-99.

My temp is always around 96.4-97.0 (LOW) during the luteal phase, and 97.2-97.7 (LOW) after Ovulation. So basically, I have PRE-O temps for POST-O temps.

I have read that a low temp isn't something to be too worried about - as long as you see a clear change in temp between phases, it means you are probably ovulating successfully. But what if my POST-O temp isn't high enough to sustain a pregnancy? After a year and a half of trying, I'm getting worried that when i finally do get pregnant, that i will miscarriage - or maybe low temps is stopping me from even conceiving?


I'm wondering if my low bbt's are REALLY low though- no one says at what TIME this range is. If I wake up and test at 5:30am, it will be a lower temp then if i wake up at 8:30am.

Your BBT steadily increases throughout the night, so what time do they assume you would have a reading of 97.2-97.7. UPON WAKING can be someone's 5:30am, or someone's 8:30am - but a 3hr difference will surely show a higher BBT

For instance, I'm post-O temping now. Today I naturally woke up at 5:15 and took my temp: 97.33. Then fell back to sleep, and naturally woke up again at 9:30am - just for kicks, i took my temp = 98.03. That's at least the 3.5-4 hours of sleep required for an accurate bbt. So which one would i want to trust? the 97.33 or the 98.03?

I've been testing my bbt at 5:30am every morning - maybe that is just too early?

But if I decided to naturally ALWAYS take my temp at 9:30am every morning, and the "normal" bbt range is 97.6-99 Post-O,and I woke up with a 98.03, then I wouldn't worry that I had low Progesterone because my waking bbt temp fell within the "normal" range.

It is only because I am taking my temp at 5:30am where my bbt is "lower" than the averages pre and post-o.

So... what TIME were they using to come up with the "normal temp range"?

I may not have a low bbt after all if the normal range is from a waking time of 8am or something.

Also... if I do have low progesterone that isn't increasing my temps, why are my boobs always so sore!? Isn't breast soreness a sign of increasing hormones, i,e: progesterone/estrogen levels? I would think if i had low progesterone, my boobs wouldnt get sore because there wasn't enough hormone surge.

Thank you!

Avatar for Cmmelissa
iVillage Member
Registered: 11-13-2008
Wed, 03-20-2013 - 3:57pm

I'm not sure if waking at a later time would make a difference or not, vegiemama on the Fertility Charting board would be the person to ask.  She's very good with answering questions about charting.  

As far as your luteal phase, I thought that length would be more vital, but you also need a good lining to sustain the fertilized egg.  Your hormone levels would play a role in that part, so changing temps could be an indicator. I think that your sore boobs would be a good sign though.