Spina Bifida Support Group
Spina bifida describes birth defects caused by an incomplete closure of one or more vertebral arches of the spine, resulting in malformations of the spinal cord. The spinal membranes and spinal cord may protrude through the absence of vertebral arches (called clefts).
I think what worked for me was that he didn't really push it or make a big deal out of it. He just kinda let me do my thing but would be there for help if I needed it in little ways. He'd buy me diapers if I needed them, or if I had an incident with incontinence while sleeping he'd just nicely tell me to go get myself cleaned up and he would have the bed changed when I came back.
So in a roundabout way, just acknowledge it, but don't put too much of a focus on it. Let him know that whatever is comfortable for him will work for you.