Why is she regressing? 7 month old

[nancy2009]

Hi, I posted about a month ago about my LO's sleep issues.  When she was 6 months she was having short 40minute naps and OT.  The initial problem was that she was always tired about an hour after her morning wake up, but would only sleep for 40minutes for all of her naps.  Another poster suggested slowly extending her morning wake time, which we did, it slowly went to 2 hours, and with some PU/PD everything went great!  Her naps extended to about 1.5 hrs.  Night sleep was 12-12.5hrs and was on a pretty good 2-3-4 schedule

This lasted for about 2 weeks =(.  This last week her night sleep has been getting shorter and shorter, she used to sleep for 12-12.5 hrs and now she sleeps for about 11-11.5hrs (I know not a big difference, but it is to me in the morning!)  and now she wakes up crying at 40minutes and it'll take me about 30minutes of PU/PD to get her back to sleep.  What's going on?  I've tried increasing her first A time to 2.5 hrs and still the same result.  Here's an example of today's EASY

E/A 6:40am-9am (BF at 6:40, solids at 8am)
S    9-940, PU/PD for 30 minutes, slept for another 30minutes
E/A 1040-140 BF at 1030 solids at 12
A 140-320pm sleep 40minutes PU/PD for 30, and slept for another 30minutes
E/A 320-730pm BF at 320 solids at 530, night time routine at 630, bath, massage, change, nurse, sleep sack, bed, put down drowsy but awake
1130pm DF
Awake at 640ish.

Why have things changed?  I don't think she's teething, and if she was, wouldn't her night time sleep be affected?  TIA...  appreciate you reading this and for your help!

[nancy2009]

Also wanted to add, her naps slowly started getting shorter and shorter.  Went from 1.5 (sometimes 2hr) to 1hr20minutes, then 1 hr, then 40minutes over a few days.  I would get her up until it went to 40minutes, should I always PU/PD when she sleeps under 1hr30min?

And before getting back to sleep was easier, sometimes in the beginning I'd need to go back up there, but I would just have to talk to her in a soothing voice and maybe PU/PD once then she'd go back, but this few days she's been harder to get back to sleep, crying very hard in the PU/PD and it taking longer every time I pick up for her to calm down.  I put her down when she arches and tries to pull away, but she just cries harder when I put her down, I let her cry for about 10-15seconds and then pick again until she arches.  Eventually she'll get into her mantra cry and that's when I stop picking her up.

[ZacsMumme]

Went from 1.5 (sometimes 2hr) to 1hr20minutes, then 1 hr, then 40minutes over a few days.  I would get her up until it went to 40minutes, should I always PU/PD when she sleeps under 1hr30min?

This sounds like she needs an A increase She is probably not that tired to nap at that time. Then after the short naps she is OT by the end of the day. I would try extending her A time 10-15mins every few days and see is she starts to sleep longer again. What do you think?

Check out these sample routines for an idea of how her day may need to start looking
http://babywhispererforums.com/index.php?topic=164030.0