When we write in English, we don't use numerals, so you need to change 5 to five. Also, the sentence doesn't make sense when you compare women and females. Both word mean the same thing if we're talking about humans. "There were five times as many women students as men students" sounds awkward because we would normally say male students. If we use male, then it would be better to use female as well. "There were fives times as many female students as male students." And; "There were as nearly as many women as men" is correct.

Both of those sentences look good as they are with their structure. However, "women students" would be considered part of "female students." So, you can't have more women than you do females because women are females.