Panty liners were a must due to the lady bits acting oddly anyway. I'm 32 weeks, had one minor incident a few months ago so started doing pelvic floors every so often and that stopped it for me. Though I've noticed baby is heavier now and bearing down on my bladder so fingers crossed no issues other than frequent loo visits.
I had a little bit of leakage the few times I was sick in trimester one but I think the act of vomiting puts such a strain on you that even if you weren't pregnant you might wet yourself a bit! Did my pelvic floors religiously and had no other problems. Am now a week post-birth and no incontinence issues (hopefully!) and everything seems to be healing nicely. It's also such a relief to no longer need to pee every five minutes!!