5m pregnant in peak summer - brother's nikkah - what to wear?

Subject line says it all: my brother has his nikkah in Lahore after Eid this year and I will be 5 months pregnant so need something appropriate for the weather, occasion that doesn't draw too much attention to my belly.

I don't live in Lahore so I would like suggestions for designers that can work with me over the Internet or where I can buy ready to wear.

Thanks, ladies