Penis Size Age Changes

As penis size changes, so do the testicles. "Starting around age 40, the testicles definitely begin to shrink," says Goldstein. The testicles of a 30-year-old man might measure 3 centimeters in diameter, he says; those of a 60-year-old, perhaps only 2 centimeters.

Curvature.

If penile scar tissue accumulates unevenly, the penis can become curved. This condition, known as Peyronie's disease, occurs most commonly in middle age. It can cause painful erections and make intercourse difficult. The condition may require surgery.

Penis Sensitivity.

Numerous studies have shown that the penis becomes less sensitive over time. This can make it hard to achieve an erection and to have an orgasm. Whether it renders orgasm less pleasurable remains an open question.

If there's a silver lining to these presumably unwelcome changes, it's this: Experts say these changes need not ruin your erotic life. One recent study involving 2,213 men in Olmstead County, Minn., showed significant declines in erectile function, libido, and ejaculatory function -- but only moderate decreases in sexual satisfaction. "Older men may be less likely to perceive these declines as a problem and be dissatisfied," concluded the study's authors.

As Goldstein puts it, "The most important ingredient for a satisfying sex life is the ability to satisfy your partner, and that doesn't require peak sexual performance or a big penis. As long as a man's partner enjoys sexual intercourse, he feels like a god."