If your labour progresses naturally, your DH will not really witness anything squirmish-ifying anyways. That only happens at the end - and many men who do say they are squirmish say that when they heard their baby was about to appear - the excitement and fascination took over and they found it easy to stomach!!
Regardless, your DH could always stand behind you and massage your shoulders, rub your lower back or simply hold your hand by your side or something when you get close to delivering - he doesn't have to witness anything he's not comfortable with.

I wouldn't stress about it hon - I would just ask him to take it as it comes.