Men and women are generally aroused in different ways. "Many heterosexual men believe that penetration and propulsion (e.g., going deep and fast) will lead women to orgasm," says Milrod. The truth is many women don't orgasm vaginally and most women need about 20 minutes of foreplay to reach prime physical arousal. Without this warm up a woman may lack natural lubrication and have decreased skin sensitivity. Arousal also elongates the vagina. Without this elongation, a man's penis is more likely to painfully bump up against a woman's cervix during penetration.
The solution: Put in that extra 20 minutes and be creative about it. This can involve massage, oral sex, and heavy petting. It can also come in the form of sexy texts or a romantic date nights, suggests Malone.