Reasons why I'm not drinking...suggestions???

Louie • 1 day over due...
I'm a pretty keen social drinker (well, I was before we started our <a href="https://glowing.com/glow-fertility-program">IVF</a> cycle), and all of the girls in our circle of friends are watching each other like hawks to guess if/when any of us get pregnant. 
I don't want anyone to know we're trying or that we might be (beta next week!), so I need excuses as to why I'm not drinking. Trust me, they WILL be paying attention.
We have a few dinner dates that we can't get out of, which is usually my perfect excuse for a cheeky vino or two.
Can anyone offer any excuses they've used before that have gone under the radar. I'm thinking medical, as they won't ask any further questions. But nothing infectious as they have kids that will be at the dinners. 
The designated driver speel won't work either, as they all know I would still have a glass at least.
Suggestions???