Polycystic ovarian syndrome and pregnancy

[PCOSandbaby]

DSis has PCOS and sometimes goes 3-5 months minus a period. She took a test 2 weeks back following a late period and it was positive. Counting back to her last period she would be around 8 weeks today but she doesn’t track ovulation and given how irregular her periods are it’s hard to tell exactly when she ovulated.

She went for a private reassurance internal scan today and it’s came back a sac with signs of a growing baby but measuring at 5.2 weeks which has got her worried, I’ve suggested contacting the EPU and advising the private scan was inconclusive in the morning to see if she can get a scan in a week or two to view progression.

She knows I’m posting here for her as she’s not got an account set up yet so just looking to see if anyone has any experience with late ovulation or PCOS in pregnancy to see if this can influence dating?

It would be impossible to tell when she ovulated if she wasn't tracking ovulation and doesn't have any type of regular cycle length.
I have PCOS but I was tracking ovulation so does make things easier!
I would tell her not to focus too much on when her last period was, in terms of thinking she's 8 weeks as she mostly likely ovulated at a random date. I would suggest going back in a week to see how things are progressing and hopefully they are.

Thanks so much for your reply I agree as shes so irregular it’s hard to try and pinpoint how far exactly she would be. Hopefully the EPU can book her in a week or two and make sure things are progressing the way they should