Many people thinks out various kinds of methods to overcome this difficulty. One way to solve this problem is to open the men's toilet to women. Obviously this solution sounds ridiculous. But after thinking over it, you may find it is seasonable and practicable(or feasible) to some extent.
I heard of this idea for the first time in a lecture given by a professor from Taiwan the day before yesterday. The speaker told us that this solution had turned to reality in his university. They had adjusted the equipment of men's toilet for the usage of women. Currently all the women can go into both men's and women's toilet, but the reverse is not permitted.