How would you handle this?

Quick background: DH and I have been together for 7 years, married for almost 4. We have a 2 year old together and I’m 35 weeks pregnant with our second.

Both DH and I have had our own history of mental health stuff, mostly depression and anxiety for both of us. I have a history of an eating disorder and DH has a history of drug use but none in probably close to 10 years prior to meeting me.

Ok so today DH very awkwardly “had” to make a trip to Walgreens (basically went an hour out of his way to go to the Walgreens by our house even though we weren’t going home until tomorrow. There were several other closer Walgreens and we easily could’ve stopped at one of them or just waited til tomorrow to go to the one by our house. Basically it was clear that he needed to go pick something up at that specific location this afternoon and didn’t want to tell me why).

So when he got back from Walgreens I see the prescription bottle he picked up is for Alprazolam/Xanax. I know DH has been on an SSRI for a while now but didn’t know he’d gotten an rx for Xanax.

I’m not mad that he’s taking Xanax if he needs it or even that he didn’t tell me but I am concerned that he might be struggling more than he’s let on. Especially with me having a baby anytime in the next 5 weeks where I’m likely to have at the very least typical postpartum baby blues and potentially even postpartum depression or anxiety, I feel like he should have told me if he was struggling.

How do I approach this without immediately getting him on the defensive so that we can have a productive conversation. I don’t want him to feel like I’m a nag but I do think with our histories and the upcoming baby we need to be honest with each other about where we are with our mental health. Help!