I am a father of 2 quite young girls. Sometimes when we're out they need to use public toilets.
I usually take them into the female toilets, because I don't want them gawking at men openly urinating (btw, I have never understood why men's toilets are designed to maximize genital display by removing all privacy measures, but that's another story). However, if the female toilets are full, I'll use the male ones because with little kids it's about T minus 2 minutes when you are first alerted to their need.
So, is it "OK" for a man go into the female toilets for the purposes of accompanying small girls?
Which countries would it not be OK in?
Which countries would it not be OK for me to bring my daughters into a male toilet?
Are there countries where I should do neither?
In my experience in USA and Australia, it's always been OK with any women who happen to be using the toilet (or "bathroom" as Americans call it, despite there being no bathing facilities present) - they can see that my intention is both honorable and harmless and the women seem relaxed and understanding about it.
If the roles were reversed - ie a mother accompanying her young sons into a male toilet - I don't think that would ever be a problem: Men don't seem to care about females in their toilet facilities, but in general the reverse is not true.