That's a common concern. Most women are apprehensive as beginners specially when paired with men during the drilling or the sparring sessions by the coach. But is that a good or a bad thing?
Men can be smelly, hairy and just big. But the advantages training with men are very relevant and the results are also quite immediate.
The single biggest advantage of training with men is the size and strength difference. Majority of men are physiologically bigger and stronger and that is a fact. When you train with someone who is bigger and stronger than you, you are forced to use the correct technique rather than trying to force situations.
The men in your class whom your coach is pairing you with are your team mates. So not only are they bigger and stronger but are also there to help you (no matter how smelly they might be!).
The end result of all this - In real self defense situation, you are already used to dealing with skilled, bigger, stronger opponents so handling an unskilled attacker becomes a lot easier. In terms of competition, you suddenly face someone who is your size, now you have the opportunity to utilize the technique you learnt plus enforce a bit of strength you gained by training with men.
So, the next time your coach pairs you with the big guy in class, just thank him and start training.