[stubish]

Late onset OCD is very much a thing, more prevalent with women, and pregnancy one of the most common triggers. Do not expect it to go away by itself.

I think you are going to need to find a professional to discuss how to handle the situation and how to get your partner to accept the help you all three need. It will likely take a few tries to meet someone interested in working the problem, rather than proscribing some pills. Getting to the point of your partner accepting the label and some techniques to help cope and reduce the anxiety OCD causes could be all it takes get things improving.

[SpouseThrowaway]

I think the stigma of pills is where the biggest problem lies in addressing mental health. The last thing I want is to put somebody on pills, unless it's 10000% the right way to go.

As I understand it, the "easiest" and safest method is exposure therapy.

[stubish]

Its pretty much the only thing recommended for OCD. Maybe meditation or mindfulness gets a look in. But you want to try to get less superficial diagnosis than some random person on the internet; the OCD behavior could be a side effect of something else, eg. comorbid GAD or many other things I'd only be guessing at.