At present, most universities enroll students by testing their ability. It is very fair system, which allows young people have the same opportunities to enter the university because they have the same test and hardship. Therefore, if university bases on sex to enroll, it will not satisfy people who have real ability in the subject which they like and want to study. Also, in our society the rate between male and female students is not equal so it is difficult to have the equal numbers of male and female students in every subject in university.
Furthermore, some subjects require different abilities. I would argue that training to become a soldier, for example, require strong and flexibility, which male students is better than female ones. In contrast, training to become a teacher in primary school require gentleness and patience, which female students dominate more than female ones. The different between male and female students is the reason, which makes the equal numbers of male and female student in every subject is not possible. Everyone has particular strength and weakness and they just do their best when they leverage their advantages.
In conclusion, universities should continue to keep the way that they have done to enroll instead of accepting the balance between male and female students in every subject. It is better to division of labor be happening