Same thing happened with DD.
My armpits laugh in the face of my deodorant/anti-persperant. My normal Dove stuff works every single day of the year, no matter the weather or amount of activity. But when I'm pregnant, I may as well not put the stuf on. I'm off to the store tonight to buy a 3rd kind of deodorant to try. I do feel the need to clarify that I don't just stink all day long, but I do have to re-apply several times a day or I will.
Also, my armpit hair is some sort of unbreakable wire right now. I shave it every day and it still looks like I've gone 2 days without shaving. DH asked me last night how long it has been since I shaved and he didn't believe me when I told him I had shaved that morning. He also got the stink eye and a nipple twist for commenting. He rubbed my back until I fell asleep. At least he learns.