Most women need about 20 minutes of clitoral or G-spot stimulation to hit the jackpot. But an estimated 24 to 37 percent of women can't climax (and smoking, drinking, emotional disorders, medications, and menopause can make things worse).
There's hope for the orgasmically challenged. Cognitive behavioral therapy, testosterone treatments, the herb ginkgo biloba, and the nutritional supplement ArginMax (which includes Korean ginseng, ginkgo biloba, vitamins, minerals, and an amino acid) have been shown to improve sexual satisfaction.
Some researchers believe that having an orgasm during sex increases the chance of conception. The theory: Oxytocin, a hormone released in peak levels during orgasm, causes uterine contractions that coax sperm toward the egg.
Besides its obvious perks, masturbating is good for your health. Studies show that orgasm can reduce sensitivity to pain, relieve menstrual cramps, and alleviate stress—possibly due to a surge in oxytocin and dopamine.
From ancient Greece to Freud's time, doctors stimulated orgasms in women via "medical massage" to treat the catchall female ailment known as hysteria. In the late 1800s, the vibrator was designed for the same purpose.