When determining when a woman’s feet stop growing, there are two distinct answers: bone growth or changes in soft tissue structure. The bones of the foot, which determine maximum length and width, cease development in the late teenage years or early twenties, marking the end of true skeletal growth. However, the overall foot dimension—the size that dictates shoe fit—can continue to change throughout adulthood due to factors unrelated to bone lengthening. These dimensional changes are primarily caused by alterations in the ligaments, tendons, and surrounding tissues that support the foot’s arch and structure.
Skeletal Maturity: The Age When Bone Growth Stops
The definitive end of foot growth is marked by the fusion of the epiphyseal plates, often called growth plates, located at the ends of long bones. These plates are composed of cartilage where new bone tissue forms, driving the lengthening of the foot bones. Once the body reaches skeletal maturity, the cartilage is completely replaced by solid bone, leaving behind an epiphyseal line. This process, known as ossification, fixes the final length of the bones in the foot.
In females, epiphyseal fusion typically begins to accelerate around bone age 13, with most growth plates closing between the ages of 14 and 17 years. The fusion of the metatarsal and phalangeal epiphyses in the foot is often complete between 13 and 15 years of age. The calcaneus, or heel bone, is one of the last to fuse, occurring around 15 to 16 years in females.
While the majority of foot bone growth is complete by the mid-teens, the cessation of overall linear growth is generally around age 20, sometimes extending into the early twenties. After this point, the foot’s skeletal length is permanent and will not increase further.
Factors That Alter Adult Foot Dimensions
Many women report their feet changing size long after skeletal maturity is reached. This dimensional change is primarily caused by the effects of gravity, aging, and weight on the foot’s soft tissue structures. Over decades, the ligaments and tendons that maintain the foot’s complex architecture can lose elasticity.
The constant pressure from standing and walking causes a gradual stretching and weakening of these supporting structures, particularly those maintaining the arch. As the arch flattens, the foot lengthens and widens slightly to accommodate the change in shape. This is often described as the foot “spreading” and may result in the need for a half-size or full-size increase in footwear.
Significant weight gain also places increased pressure on the feet, compounding the effects of gravity and age on the ligaments. This added mechanical stress contributes to the flattening of the arch, forcing the foot structure to expand. Additionally, the fat pads on the soles of the feet can thin out with age, which changes the internal cushioning and how a shoe fits, sometimes making a shoe feel tighter.
Pregnancy and Hormonal Impact on Foot Size
A common cause of foot size change in women is related to childbearing. During pregnancy, the body releases increased levels of the hormone relaxin. While primarily intended to loosen pelvic ligaments for childbirth, relaxin circulates throughout the body and affects ligaments everywhere, including those in the feet.
The relaxation of the pedal ligaments allows the arch of the foot to depress and flatten under the increased weight of pregnancy. This structural change, combined with fluid retention and weight gain during gestation, causes the feet to become longer and wider. Studies suggest that a majority of women experience some increase in foot length or width during this period.
While some size increase is temporary due to swelling, the ligament laxity caused by relaxin can lead to a permanent increase in foot size for many women. The stretched ligaments may not fully return to their pre-pregnancy length, meaning the change in foot dimension can be lasting.