Dog STINKS in heat

I’m sure this has been posted before but is it normal that my dog absolutely genuinely stinks during her first heat cycle? She’s going to be spayed soon so don’t worry my poor girl isn’t going to be bred. I’m actually struggling to have her too close to me because she really truly just smells bad - we’ve been keeping her clean and she even had a groom yesterday but the smell coming off her is just shocking!!!