A weak pelvic floor usually results from a combination of factors rather than a single cause. Pregnancy, hormonal changes, chronic straining, genetics, surgery, and even certain types of exercise can all damage or gradually weaken the muscles and connective tissue that support your bladder, uterus or prostate, and rectum. Understanding which factors apply to you is the first step toward addressing the problem.
What Your Pelvic Floor Actually Does
Your pelvic floor is a group of muscles and connective tissue that stretches like a hammock across the base of your pelvis. These muscles hold your pelvic organs in place, help you control your bladder and bowel, and contribute to sexual function. When they weaken, you might notice urine leaking when you cough or sneeze, a heavy or dragging sensation in your pelvis, difficulty fully emptying your bladder, or reduced sensation during sex.
Clinicians assess pelvic floor strength on a 0 to 5 scale during an internal exam: 0 means no detectable contraction, 1 is a faint flicker, 2 is weak, 3 is moderate, 4 is good with an upward lift, and 5 is strong. Many people with symptoms fall somewhere in the 1 to 3 range without realizing their muscles have lost significant function.
Pregnancy and Childbirth
Pregnancy alone changes the pelvic floor. The opening in the pelvic floor muscles widens progressively throughout pregnancy as the growing uterus adds weight and pressure. But the biggest damage typically happens during the pushing stage of labor, when the baby’s head passes through that opening.
The pelvic floor muscles have a remarkable ability to stretch. The inner fibers can elongate to 2.5 times their resting length without tearing. Still, tearing and detachment do occur, especially during assisted deliveries. Forceps delivery carries a seven-fold increased risk of the muscle pulling away from the bone compared to an unassisted vaginal birth, and a four- to five-fold increased risk compared to vacuum-assisted delivery. Vacuum delivery, by contrast, carries a risk similar to spontaneous vaginal birth. This type of muscle detachment doesn’t occur with cesarean delivery.
The long-term consequences are significant. In Western countries, roughly 20% of women will eventually need surgery for urinary incontinence or pelvic organ prolapse at some point in their lives.
Hormonal Changes After Menopause
Estrogen does more than regulate your reproductive cycle. Estrogen receptors are found throughout the pelvic floor: in the urethra, bladder, pelvic muscles, and the ligaments that hold everything in place. When estrogen levels drop during and after menopause, these tissues respond by thinning and losing structural integrity.
Specifically, lower estrogen leads to less collagen production and more collagen breakdown in the pelvic tissues. Collagen is the protein that gives connective tissue its strength. Research on topical estrogen therapy has shown that applying estrogen to vaginal tissue for six or more weeks increased the production of mature, strong collagen, reduced the activity of enzymes that break collagen down, and increased the thickness of the vaginal wall. This tells us that estrogen withdrawal does the opposite: it accelerates tissue thinning and weakening. If your pelvic floor symptoms appeared or worsened around menopause, this hormonal shift is a likely contributor.
Chronic Pressure on the Pelvic Floor
Anything that repeatedly pushes downward on your pelvic floor can gradually overwhelm its ability to bounce back. Chronic constipation, obesity, a persistent cough (from asthma, smoking, or lung disease), and frequent heavy lifting all increase the pressure inside your abdomen, which pushes directly against the pelvic floor.
Engineering models of the pelvis show exactly where this pressure does the most damage. The areas most vulnerable to injury are where the pelvic floor muscles attach to the side walls of the pelvis and where the ligaments connect to the pelvic bones. The connective tissue along the sides of the pelvis experiences higher tension and shearing forces than the tissue in the center, which helps explain why prolapse often starts with organs shifting sideways before dropping downward. Years of straining on the toilet or carrying excess weight create cumulative stress on these vulnerable attachment points.
Pelvic Surgery
Hysterectomy is one of the most common surgeries linked to later pelvic floor problems. One review found that women over 60 who had undergone a hysterectomy had a 60% higher rate of urinary incontinence than women who hadn’t. A large multi-center study found that hysterectomy patients were 1.7 times more likely to need prolapse surgery later compared to women who kept their uterus.
The damage happens in two ways. First, the surgery itself can cut through the connective tissue (called fascia) that physically supports the pelvic organs. Second, nerves that supply the pelvic floor muscles run through the ligaments and tissue that are cut or disturbed during the procedure. There are at least three locations where nerve supply to pelvic floor muscles can be injured during a hysterectomy. When those nerves are damaged, the smooth muscle they control gradually wastes away. Tissue samples from women with prolapse show significantly more muscle atrophy than samples from healthy controls, confirming this pattern of nerve-related muscle loss. Prostate surgery in men can cause similar nerve and muscle disruption.
High-Impact Exercise and Athletics
Exercise is generally protective for most of your body, but certain types of high-impact activity place extreme demands on the pelvic floor. A study of 325 athletes at the 2024 World Athletics U20 Championships found that nearly half reported pelvic floor symptoms. Long-distance runners had the highest rates, with 73.7% reporting symptoms, followed by combined-event athletes at 57.1%.
Jumping, sprinting, and rapid changes of direction were the most common triggers. About 13% of athletes across both sexes reported urinary leakage specifically during athletic activity, with middle-distance runners most affected. Athletes who trained in additional sports beyond their main event were also more likely to have symptoms during daily life. The repeated impact forces of landing and the sharp increases in abdominal pressure during explosive movements challenge the pelvic floor in ways it may not fully recover from between training sessions, especially without targeted pelvic floor conditioning.
Genetics and Connective Tissue
Some people are born with connective tissue that’s structurally less resilient, making them more susceptible to pelvic floor weakness regardless of other factors. The key lies in collagen, the protein that gives your ligaments, fascia, and muscle attachments their tensile strength. Your body produces several types of collagen, and the ratio between them matters. A higher proportion of type I collagen relative to type III means stronger tissue. A lower ratio means more lax, stretchable tissue that’s easier to damage.
The genetic component is substantial. Women with pelvic organ prolapse are significantly more likely to have family members with the same condition. In one study, mothers of women with prolapse were nearly four times more likely to have prolapse themselves compared to mothers in the control group. Sisters were nearly nine times more likely. A large twin study confirmed that heredity plays a significant role.
The most well-known inherited connective tissue condition linked to pelvic floor weakness is Ehlers-Danlos syndrome, which involves defects in multiple collagen types. But you don’t need a diagnosed connective tissue disorder to carry genetic variations that make your pelvic floor more vulnerable. If you have joint hypermobility (you’re unusually flexible), varicose veins, or a history of hernias, your collagen makeup may be predisposing you to pelvic floor problems. Women with joint hypermobility who develop prolapse tend to have significantly higher concentrations of the weaker type III collagen in their tissues.
Sedentary Lifestyle and Aging
Like any muscle group, the pelvic floor weakens when it isn’t used. Sitting for long periods shortens the hip flexors and reduces blood flow to the pelvic region, while the muscles themselves lose tone from disuse. Aging compounds this: muscle mass naturally declines with age throughout the body, and the pelvic floor is no exception. Combined with the hormonal changes of menopause or the gradual testosterone decline in men, aging creates a slow but steady erosion of pelvic floor strength that can take years to become noticeable.
Why Multiple Factors Matter
Pelvic floor weakness rarely has a single cause. A woman with a genetic tendency toward lax connective tissue who has two vaginal deliveries, gains weight in midlife, and then goes through menopause is dealing with four overlapping risk factors, each compounding the others. Similarly, a man who has prostate surgery after years of chronic constipation and a sedentary job faces multiple sources of damage converging on the same muscles. Identifying which factors are relevant to your situation helps you and a pelvic floor therapist focus on what’s most likely to improve your symptoms, whether that’s targeted strengthening exercises, managing chronic pressure, addressing hormonal changes, or a combination of approaches.