The folds of skin on either side of the vaginal opening are called the labia. There are actually two sets: the labia majora (outer lips) and the labia minora (inner lips). Together with the clitoris and other structures, they make up the vulva, which is the correct term for the entire external genital area.
Outer Lips: The Labia Majora
The labia majora are the larger, fleshier folds you can see from the outside. They run vertically on either side and encase all the more delicate structures underneath. These folds contain fatty tissue that becomes engorged with blood during arousal, and they grow hair after puberty. They also contain sweat and oil-producing glands that help keep the area lubricated and protected.
Think of the labia majora as a protective outer layer. Their main job is to shield the urethra, vaginal opening, and inner lips from friction, debris, and bacteria.
Inner Lips: The Labia Minora
The labia minora are thinner, hairless folds of skin just inside the outer lips. They start near the clitoris at the top and extend downward past the vaginal opening. The uppermost portion forms the clitoral hood, a small cover that protects the clitoris and helps moderate sensation during stimulation so it feels pleasurable rather than painful.
Unlike the outer lips, the inner lips contain no fat and no hair follicles. What they do have is a dense concentration of nerve endings and specialized sensory receptors, including receptors tuned to light touch and pressure. This makes them the second most sensitive part of the vulva after the clitoris. A rich blood supply gives them a pinkish color and causes them to swell noticeably during sexual arousal, increasing sensitivity even further.
What “Normal” Looks Like
Labia vary enormously from person to person. A meta-analysis of over 6,000 patients found that inner lip length averaged about 49 mm but ranged widely, and inner lip width averaged about 22 mm with similarly broad variation. The statistical spread was so large that researchers noted greater than 99% heterogeneity across measurements, meaning there is no single “standard” size or shape.
Some people have inner lips that tuck neatly inside the outer lips. Others have inner lips that protrude well beyond them, and this is equally normal. Asymmetry is common too. One side can be longer, thicker, or differently shaped than the other. Color ranges from pink to brown to dark purple, and all of these are typical variations.
How the Labia Change Over Time
Hormones reshape the labia at every major life stage. At puberty, rising estrogen causes both sets of lips to grow larger and thicker, and the outer lips develop hair. During pregnancy, increased blood flow can make the labia appear darker or more swollen. Monthly hormonal shifts during the menstrual cycle can cause subtle changes in fullness and sensitivity as well.
After menopause, declining estrogen reverses many of these effects. The skin thins, loses elasticity, and becomes drier. The labia may appear smaller, paler, and less defined in outline. This thinning also makes the tissue more fragile and more prone to irritation from friction or contact with chemicals in soaps and detergents. Using a gentle, fragrance-free cleanser and a vulvar moisturizer can help manage the dryness and sensitivity that come with these changes.
Labial Hypertrophy
When the inner lips are long enough to cause physical discomfort, chafing during exercise, difficulty with hygiene, or significant emotional distress, it’s sometimes called labial hypertrophy. There is no universally agreed-upon measurement that defines it. A review of 45 studies found that only about 18% provided explicit diagnostic criteria, and definitions varied widely between practitioners. What matters clinically is whether the size causes functional problems or psychological distress, not whether the labia exceed a specific number on a ruler.
For people who do experience persistent discomfort, surgical reduction (labiaplasty) is an option, but it’s typically considered only after conservative approaches like switching to softer clothing or using barrier creams have been tried. For anyone under 16, guidelines emphasize focusing on whether real functional symptoms exist rather than appearance alone.