Delayed period since starting

[Thischarmlessgirl]

Hello
I am on W2 D5 of starting. My period was due just as I began (around 10 days ago) but I’m still waiting. I’m usually very regular (on HRT) I have PCOS. I’m not pregnant. Just wondering if this was usually at the beginning, I haven’t lost very much weight at all yet, so it can’t be that.
Would appreciate any advice/reassurance
Thanks

I am post menopause/on continuous HRT so don't have periods anymore so can't comment on them.

Are you on oral HRT? If yes, did your provider let you know Mounjaro can affect it's absorption?

It never affected my cycle at all, I am regular as clockwork

Thank you - I am, and no they did not. Ok I need to look into that as perhaps that’s influencing it, however that’s began really early if it has. Maybe I should speak to the GP about switching to gel/patches.

Mounjaro affected my cycle . I’ve not had a jab the last 2 weeks and I’m due tomorrow. But when I have had my jab I’ve been late and very very light !

@bagheera92 thank you that’s useful

@Thischarmlessgirl

https://www.pcwhs.co.uk/_userfiles/pages/files/resources/glp1_contraception_hrt_article.pdf

https://thebms.org.uk/wp-content/uploads/2025/05/23-BMS-TfC-Use-of-incretin-based-therapies-APRIL2025-E.pdf

You need to speak to your Dr about your oral HRT alongside Mounjaro. If it is the progesterone that is oral you need to switch to non-oral or increase progesterone dose for the first 4 weeks of starting Mounjaro and each Mounjaro dose increase to continue to protect your endometrial lining. If your estrogen is oral they need to consider that too.

You might need to share the links with your Dr if they are not aware as advice only came out in April this year.

Providers really should be telling new patients this when they declare their HRT during consultation.

@WeAllHaveWings thank you for the info. I will do. Now to try to get a GP appointment

Yes re period. I am 50 but still pretty regular. My first one was really delayed - 6 weeks late.

From then on in, back to regular 26ish days. This month I think will be a bit later but I am 50 and no hrt so more likely that.