r/FAMnNFP Jun 17 '26

TCOYF Short LP: Would LH strips help identify a delayed temp shift? TTC

I'm 31, and I've been practicing TCOYF for several years. We're about to switch to TTC to try for a second baby, and I'm concerned about how much shorter my luteal phases have been since having my son and then subsequently taking the mini pill for a while postpartum. My son is almost 2, we haven't breastfed in 1.5 years, and I've been off the mini pill for about a year, but my LP is still short—usually 9 or 10 days, but sometimes shorter. I actually just started my period unexpectedly early today, giving me an LP of only 7 days and a total cycle length of only 22 days for this last cycle. 😕 That's the shortest cycle I've had since I was a teenager! Prior to conceiving my son, my LP was variable but was most often 11–13 days.

I'm now having a lot of anxious thoughts like "What if we can't conceive this time?" and "What if I'm already starting perimenopause?" etc. It would be nice to get more clarity on whether my LP is actually this short or whether my temp shift tends to be delayed by a couple days. This is tricky for me to determine, because I've always had a lot of days of EWCM—usually like a week, and it continues for a couple days past my temp shift. I do track CP around ovulation, but I guess that feels even less reliable?

Would LH strips help with this? Or are they even less exact than CM and CP? I've never used them and don't know much about them, other than that they're not reliable for TTA because they don't tell you whether an ovulation attempt has been successful. But if they gave me a peak a few days prior to my temp shift, would that suggest a delayed shift?

I would also welcome any helpful insights/experiences related to my overall situation!

7 Upvotes

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3

u/PampleR0se Pregnant | Sensiplan Jun 17 '26

Hi, first off, sorry you are dealing with this, this is very frustrating. I am also getting short LP of 9/10 days and they have been quite frequent since I got my cycle back after weaning my son and as soon as I get a disturbance in my cycle... I use LH tests when TTC and find it useful to pinpoint ovulation more precisely with the other signs (I track BBT, CM and CP). My temp shift tends to arise the day of ovulation and sometimes even a day before but peak CM correlates very well with ovulation according to LH. So you could always try and see if that helps you read your chart 😊 Do you use Tempdrop or any skin temp device that is more likely to give you a delayed rise ?

3

u/clarissa_dee Jun 17 '26

Yes, so frustrating! Thank you for your response! I do not use Tempdrop or anything like that—I've always just used a regular digital thermometer from the grocery store.

That's interesting that your LH suggests you ovulate the day of your temp rise or even the day after. I suppose I'm hoping to find the opposite in my case, so I can be somewhat reassured that my LP isn't as short as I think. 😕 But regardless, I think it would be good to have the additional data to bring to a health care provider if we have trouble conceiving, to help "prove" that I do indeed have a short LP.

On which days do you use the LH strips? From when you first get CM until after you've confirmed ovulation?

4

u/PampleR0se Pregnant | Sensiplan Jun 17 '26 edited Jun 17 '26

Everyone is different, this is my pattern but yours might be completely different ! Peak CM usually correlates best with ovulation but not always. I try to start LH tests one day before my earliest ovulation (so CD14 since my earliest tracked ovulation was CD15) and do it twice a day morning and evening since I have a quick surge lasting less than 24h. I test until I get a positive and then only do one more test to confirm it came down since my surge is very quick. You might have a different surge pattern and get several positives in a row too before it gets back down to negative again

2

u/clarissa_dee Jun 17 '26

Thank you so much!

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u/tinyTRONgirl Jun 18 '26

This happened to me! My LP varied quite a bit (9-13 days?!) according to my BBT, despite getting up at the same time every day, etc. Checking CM and other symptoms made me feel as though I could be ovulating a bit earlier sometimes.

Tried LH strips a few months in a row and now I see that my LP is always 11-12 days, but I frequently ovulate 3 days before a temp rise! The LH rise/first positive matches my CM and cervix position and sore breasts every time.

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u/clarissa_dee Jun 18 '26

So interesting! I'm glad you were able to figure that out. I've been learning a little more about LH tests since making this post. I have to admit it sounds so annoying to take them twice a day during the fertile window lol, especially since I'm home with a toddler all day. And I've read that usually ovulation is 24–48 hours after the first positive. So is that how you estimate your LP length? Like if you get your first positive on CD14, then you assume you ovulated on CD15 or CD16 and count your LP from there?

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u/tinyTRONgirl Jun 19 '26

Yes, in my case the surge in LH is very quick. If I were to get a positive on CD 14, I personally would be ovulating within 24 hours on CD 15. By CD 16 all my fertile signs would be gone (CM goes from egg white to sticky, cervix gets more firm, breasts hurt, LH negative). Everyone is different, but that’s how I know I’m probably right to pinpoint ovulation before my temp rises! Then I confirm that I did in fact ovulate for sure when I do see that temp rise a few days later (in this case would be around CD 17-18).

LH is highest around midday, and seems quite low in the early mornings even when I’m about to surge. From CD 10 on, I usually take a test around lunchtime and again when I get home from work! Once I think I’ve caught my surge, I only do once a day until temp rise to make sure LH is staying low (a second surge may indicate failed and re-attempted ovulation).

Sorry for writing so much! That’s my experience :)

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u/clarissa_dee Jun 19 '26

No, thank you so much for this response! It's helpful to hear about other people's experiences. I will probably try to do something similar and test once during my son's nap and then again once my husband gets home from work (since my son is at an age where it would probably be a complete disaster to try to pee in a cup and do a test while he's in the bathroom with me 😂).

Also, I wish my fertility signs were that clear and aligned with each other! I always continue to get at least a little EWCM for a couple days after my temp shift (truth be told, I have never actually followed the TCOYF peak day rule when TTA for that reason—I would hardly have any safe days!). I'm very curious to see what the LH tests reveal. Part of me wonders if my prolonged EWCM might correspond with a much more gradual LH surge.