A vaginal boil looks like a swollen, red lump under the skin near the vulva, often resembling a large pimple. It typically starts as a firm, tender bump and gradually develops a visible white or yellow center (called a “head”) as pus collects inside. Most boils range from pea-sized to marble-sized, though some grow larger.
How a Boil Changes Over Time
Vaginal boils don’t appear fully formed. They progress through a recognizable pattern that can help you identify what you’re dealing with.
In the first day or two, you’ll notice a firm, reddish bump that’s tender to the touch. The surrounding skin often looks pink or inflamed. At this stage it can easily be mistaken for an ingrown hair or a pimple, because there’s no visible pus yet.
Over the next several days, the bump grows larger and softer as your body fights the infection and pus accumulates. The redness typically spreads outward from the center, and the skin over the lump may look stretched or shiny. This is when the pain usually peaks, since pressure is building under the skin.
Eventually, a white or yellowish point forms at the surface. This is the “head” of the boil, and it signals that the pocket of pus is close to draining. Once it opens (either on its own or with medical help), you’ll see thick, sometimes blood-tinged fluid drain out. The pain drops significantly after drainage, and the lump flattens as it heals over the following days to weeks.
What Causes Them
The vast majority of vaginal boils are caused by Staphylococcus aureus, a type of bacteria that naturally lives on your skin and inside your nose. The infection starts when this bacteria gets into a hair follicle or a small cut in the skin. Your body responds by sending white blood cells to the area, creating the pus-filled lump you see and feel.
Shaving, friction from tight clothing, and sweat all make the vulvar area especially prone to these infections. Any break in the skin, even a tiny nick from a razor, gives bacteria an entry point.
Boils vs. Ingrown Hairs
An ingrown hair and an early boil can look almost identical: a small red bump, slightly painful, right where hair grows. The key difference is depth. An ingrown hair is usually superficial, with a tiny pustule sitting right at the skin’s surface. If you look closely (sometimes with a magnifying glass), you can often see the curled hair trapped beneath the skin.
A boil forms deeper in the tissue. It feels like a firm marble under the skin rather than a surface-level bump. It also grows larger and more painful over days, while ingrown hairs tend to stay small and resolve more quickly. If a bump keeps expanding and develops that characteristic white or yellow head, it’s more likely a boil than a simple ingrown hair.
Boils vs. Bartholin Cysts
Bartholin glands sit on either side of the vaginal opening, and when one of their ducts gets blocked, a cyst forms. A Bartholin cyst appears as a round, usually painless lump right at the lower edge of the vaginal opening, specifically at about the 4 o’clock or 8 o’clock position. It only occurs on one side at a time.
A boil, by contrast, can show up anywhere on the vulva where hair grows: the outer labia, the bikini line, the crease of the thigh. A Bartholin cyst also tends to feel smooth and fluid-filled, like a small water balloon, whereas a boil feels firmer and more inflamed. If a Bartholin cyst becomes infected and turns into an abscess, it starts to look and feel much more like a boil, with redness, swelling, and significant pain.
Boils vs. Herpes Sores
Genital herpes sores are sometimes confused with boils, especially in mild cases where only a few lesions appear. But the two look quite different once you know what to watch for. Herpes typically starts as a patch of red, swollen skin that develops clusters of small blisters, not one single large lump. These blisters are superficial, filled with clear fluid, and break open into shallow, painful sores that scab over and heal within two to six weeks.
A boil is a single, deep lump filled with thick pus. It doesn’t cluster, doesn’t blister, and doesn’t ulcerate into an open sore the way herpes does. If you’re seeing multiple small, grouped blisters rather than one firm bump, that’s a different situation entirely.
When Boils Keep Coming Back
A single boil is common and usually not a sign of anything serious. But if you’re getting boil-like lumps repeatedly in the groin, armpits, or other areas where skin rubs together, it may be a condition called hidradenitis suppurativa (HS). In its early stages, HS looks exactly like ordinary boils or acne, which makes it hard to identify at first.
The hallmarks of HS are recurrence and scarring. The lumps come back in the same general areas, heal slowly, and can eventually create tunnels under the skin that connect separate lumps. If you’ve had three or more boil-like bumps in the groin area over six months, especially if they leave scars or seem to connect beneath the surface, HS is worth investigating.
Home Care and What to Expect
Most small vaginal boils resolve on their own. The best thing you can do is apply a warm, damp washcloth to the area for about 10 minutes at a time, several times a day. The warmth increases blood flow and helps the boil come to a head and drain naturally. Keep the area clean and avoid squeezing or popping the boil, which can push bacteria deeper into the tissue and worsen the infection.
Wear loose, breathable underwear while a boil is healing. Cotton is ideal. Tight synthetic fabrics trap heat and moisture, exactly the environment bacteria thrive in.
Signs of a More Serious Infection
Most boils stay contained, but occasionally the infection spreads beyond the original lump. Watch for red streaking that radiates outward from the boil, warmth that extends well past the bump itself, or swelling that seems to be getting worse rather than better after several days. Fever, chills, or feeling generally unwell alongside a boil suggest the infection may have reached surrounding tissue or the bloodstream.
A boil that grows rapidly, becomes extremely painful, or doesn’t improve after a week of warm compresses likely needs professional drainage. This is a quick procedure where a small incision is made to release the pus. Antibiotics are typically reserved for cases where the surrounding skin shows signs of spreading infection, or for people with conditions that weaken the immune system.