My doc assured me that in order for it to be too hot for baby, it would have to be too hot for you. As in, you're dizzy, sweating, breathing faster, etc...
So... as long as your body is not signaling to you "get me out!!" you're fine. I take them pretty hot.
I still have baths and the water is warm enough to make my skin pink. I have read that it's ok as long as you don't start to sweat...when you do, put cold water in or get out. I never reach that point, but maybe because I don't sit in the tub for a long time.
I asked my MW directly about this as i was dying for a proper hot bath. She said exactly what other ladies said here, as long as you can get in without it hurting you then its totally fine. Because the bath continues to cool the whole time you are in it it doesn't raise your body temperature enough or for long enough for it to be of any harm to the baby. Saunas, steam rooms, jacuzzis and hot tubs etc should be avoided though as they maintain their temperature, so even if they are cooler than your bath initially the constant temperature can raise your body temperature without you noticing it.
Baths are totally FINE while pregnant, its hot tubs, and saunas that you have to avoid. The reason for this, is if your temperature goes above 101 it can be dangerous to baby...baths are nothing to be afraid of. When I was pregnant with my son I had baths all the time!! And he is a healthy vibrant little 2 year old! Nothing wrong with him. If you are really worried just double check with your doctor. But he/she will say the same thing...its more to do with moms body temperature than anything else. Best of luck!
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