I often get hens asking me if they can attend a hen party pregnant & I always say yes. Of course if you're doing something active then you should get medical advice first & not do anything beyond what you'd normally do, but being pregnant certainly does not mean you should miss out on the fun. ...But perhaps steer clear of the Jaeger.
Being 8.5 months pregnant myself (I will have popped by the time this is posted, eek!), I worried how I would get through my friend's hen party pregnant, not to mention my birthday, Christmas and New Year's Eve. But survive I did. (And that's a feat when you like bubbly as much as I do!) I actually enjoyed all those occasions just as much as if I'd been my 'normal' self, if not more. I could remember the whole evening & couldn't deny feeling a teeny bit self righteous that I was not nursing a hangover the next day.
If doing something active whilst pregnant is far too scary a concept, then there are loads of alternative hen party ideas which you can book as part of a unique hen party. Perhaps you could book a craft workshop for your hen party where you make wedding bunting - a fantastic alternative hen party activity which everyone can do, plus it will add to the wedding decor.
So please don't think a bump is reason to not partake. We have loads of classy hen party activities in Devon and London you can choose which all hens (sober or otherwise!) can enjoy. Have a look through our Hen Party Activities & get in touch if you'd like any more advice on running a hen party with pregnant attendees.