Posting on behalf of a family member. Possible fertilty problems

[ScreamandYellowFeathers]

My SIL is having an ultrasound scan and internal scan tomorrow.
The reason for it is that she used to have regular periods. So regular that she even knew what time they would start. Now they have become very irregular going from 23 days to 33 days.
Twice now she has also felt a popping sensation at her left hand side and this has happened every other month.

She's clueless as to what it could be and although shes not shown it, I think shes quite worried. It also doesnt help that she wont get the results of the scans until January.
I wondered if it could be something like PCOS or Endometriosis but I thought that they were something that you always have IYSWIM not just developing problems. The other thing was a burst cyst but I have heard with that comes alot of pain and she said she doesnt get pain with it, just a quick jab at the same time as the popping and nothing.

Does anyone know about this sort of thing
or has anyone suffered with a similar problem?

Could the popping be the egg releasing at ovulation? Is it the same side every month?

Don't know much else I am afraid.

Yes its the same side. Left I think she said.
She has already done a bit of temping which she said she noticed a slight increase at one point in the month but nothing major and has now been told to test her CM but she said she doesn't get any.

Don't know much I am afraid but at least she is being checked. Can't beleive the results will take that long though.

I know, I think thats the worst bit just waiting.
I doubt the sonographer will let on much.

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