A FUPA, short for “fat upper pubic area,” develops when excess fat or loose skin accumulates over the mons pubis, the soft mound of tissue that sits over your pubic bone. This area is naturally composed of fatty tissue, and the amount varies from person to person. Several factors determine whether you’ll carry noticeable fullness here, from genetics and hormones to life events like pregnancy and major weight changes.
Genetics and Body Fat Distribution
Where your body stores fat is largely determined by your genes. Researchers have identified more than 460 genetic markers linked to fat distribution patterns, and these patterns vary across ethnic groups independent of overall body weight. That means two people at the same weight can look very different in how fat sits on their bodies. Some people are genetically predisposed to carry more fat in their lower abdomen and pubic area, while others store it primarily in their hips, thighs, or upper body.
What’s striking is how much we still don’t know. All the genetic markers identified so far explain only about 4% of the variation in body fat distribution. So while genetics clearly play a major role, the exact mechanisms are complex and poorly understood. The practical takeaway: if your parents or close relatives carry weight in their lower belly, you’re more likely to as well.
Hormones and Stress
Hormonal shifts are one of the strongest drivers of fat storage in the lower abdomen and pubic region. Cortisol, the hormone your body releases during stress, is directly linked to abdominal fat accumulation. Research has shown that people who secrete more cortisol during stressful situations tend to carry more fat around their midsection. Chronic stress, poor sleep, and high-pressure lifestyles keep cortisol elevated, which promotes fat storage in exactly this area.
Estrogen also plays a significant role. During reproductive years, estrogen influences where women deposit fat, often directing it toward the hips, thighs, and pubic region. As estrogen levels drop during perimenopause and menopause, the body can redistribute fat in ways that make the upper pubic area more prominent. Lower estrogen also reduces collagen and skin elasticity in the genital region, which can make existing fat appear puffier or less supported.
Insulin resistance, which develops from chronically high blood sugar, encourages your body to store fat rather than burn it. This tends to concentrate in the abdominal area, including the lower belly and mons pubis.
Weight Gain and Weight Loss
Gaining weight is the most straightforward cause. When you take in more calories than you burn over time, your body stores the excess as fat. The mons pubis is one of the areas where fat cells expand, and because it’s a small, compact area, even modest fat gain can create a noticeable change in appearance.
Paradoxically, significant weight loss can also create or worsen a FUPA. When someone loses a large amount of weight, especially rapidly, the skin doesn’t always bounce back. Collagen fibers become thinner and less dense after major weight loss, and the elastic fiber network sustains damage. The result is loose, redundant skin that hangs over the pubic area. Some natural skin contraction occurs during the first year after reaching a stable weight, but after that point, little additional tightening happens on its own. For people who have lost 50 pounds or more, this excess skin can be a persistent issue that diet and exercise alone won’t resolve.
Pregnancy and C-Sections
Pregnancy stretches the abdominal skin and fascia significantly, and the lower belly and pubic area often bear the brunt. Weight gained during pregnancy frequently concentrates in the midsection, and postpartum hormonal shifts can make it harder to lose fat from this region.
C-sections add another layer. The surgical incision runs along the lower abdomen, and the scar tissue that forms can tether the skin, creating a visible shelf or overhang above the scar line. Some women develop a bulging mons pubis after a cesarean delivery. That said, research looking at the actual dimensions of the mons pubis after C-sections found that even repeated surgeries have minimal measurable effect on its size. The visual change is often more about how scar tissue pulls the surrounding skin than about the mons itself getting larger.
Aging and Skin Changes
As you age, your body produces less collagen and elastin, the proteins that keep skin firm and resilient. This happens everywhere, but the pubic region is particularly affected. After menopause, reduced estrogen accelerates the loss of collagen, elastin, and adipose tissue in the genital area, leading to structural changes. The skin becomes thinner and less supportive, which can cause fat that was always present to sag or become more visible. Even without gaining weight, the natural loss of skin integrity with age can create the appearance of a FUPA where one didn’t exist before.
Posture and Body Mechanics
Poor posture can make a FUPA look more prominent than it actually is. An anterior pelvic tilt, where your pelvis tips forward and your lower back arches excessively, pushes the lower abdomen and pubic area outward. This is common in people who sit for long hours or have weak core muscles. Correcting the tilt through core strengthening and hip flexor stretching won’t remove fat, but it can reduce how much the area protrudes.
Why It’s Hard to Lose
The mons pubis is one of the most stubborn areas for fat loss. You cannot spot-reduce fat from any specific body part, and the pubic area tends to be one of the last places your body pulls fat from during a calorie deficit. Even people who achieve a lean physique through diet and exercise often retain fullness here. The area has a high concentration of fat cells, and while those cells can shrink with weight loss, they don’t disappear.
When loose skin is the primary issue rather than excess fat, no amount of exercise will tighten it. The structural damage to collagen and elastic fibers after major weight loss or aging is permanent. Surgical options like a monsplasty or targeted liposuction exist for people who want to reduce the area, but for many people, a visible mons pubis is simply a normal variation in body shape rather than a problem to solve.