The wrist brace you choose should have a sturdy stiff insert
that is along the palm and wrist area.

You HAVE to sleep with something that prevents you from flexing that hand. Eventually your muscles will LEARN to hold your hand this way even during the day. (muscle memory)

I started with the braces during my pregnancy 31 yrs ago since my carpal tunnel. Compressing that nerve, can cause pain and radiate up your whole arm. My Carpal tunnel was so severe in my 5th month, I lost 80% of my functions (EMG done). That was dramatic and the braces really helped. If you lose functions, you can get a steroid injection into that wrist. I did it once, and not in my left (mine was bilateral). It helped some.
In women, who have this often at the end of the pregnancy the condition resolves pretty much. I still have some flares, but not like before. I use braces still today, usually when I overdo that hand. Gardening and sewing will set me off again. I can only sew by hand now for about 20 minutes so projects can take me a while to finish. But typing does not bother it much anymore.
It can be problematic if my blood sugars are too low, or if I cheat and have ice cream or some dessert thing which will cause a swing from high to low blood sugar that day.

I also find that the magnesium lotion, rubbed into the wrists and ventral arm areas at night reduce the minor symptoms that I have tremendously. That was an added benefit for me.