Belly buttons, also known medically as the navel or umbilicus, are an anatomical feature every person has. They form as a result of the severing of the umbilical cord after birth, which is the connection between a baby and the mother during pregnancy. The umbilical cord supplies oxygen and nutrients, and once it’s cut after birth, the remaining tissue forms a scar, which is what we see as the belly button.

Although belly buttons serve no biological purpose after birth, they come in a variety of shapes and appearances, influenced by how the umbilical cord was cut, the healing process, body structure, and other factors such as body fat and abdominal wall structure. In cosmetic surgery, particularly in procedures like abdominoplasty or “tummy tucks,” the shape of the belly button is often an important consideration. We explore the most common shapes of belly buttons, their causes, and relevance in procedures.

1. Innie Belly Button

An “innie” is the most common type of belly button and is characterized by a small inward fold or depression in the abdominal wall. This occurs when the tissue of the umbilical stump pulls inward during the healing process after the umbilical cord is cut.

• Appearance: It can appear as a small hole or a deeper indentation.
• Frequency: Roughly 90% of the population has an innie.
• Variation: Innies vary in depth and width, with some being quite deep and others shallow.
• Considerations: In plastic surgery, creating or preserving a natural-looking innie belly button is a key objective, especially in abdominoplasty or other body contouring procedures. Some people may seek surgery to convert an “outie” belly button into an innie for cosmetic reasons.

2. Outie Belly Button

An “outie” belly button, although less common, occurs when a small portion of the umbilical scar tissue protrudes outward, rather than being pulled inward.

• Appearance: This type can range from a slight outward protrusion to a more pronounced bump.
• Frequency: Around 10% of people have an outie.
• Causes: Outies can sometimes be caused by a small umbilical hernia, where a bit of tissue or part of the intestine pushes through the abdominal muscles at the belly button site. In most cases, it is not harmful and doesn’t require medical treatment unless complications arise.
• Surgical Considerations: Some people with outie belly buttons may choose to undergo umbilicoplasty, a cosmetic surgery procedure to reshape the navel, particularly if the outie is associated with an umbilical hernia or they prefer the appearance of an innie.

3. Horizontal Belly Button

A horizontal belly button, as the name suggests, is shaped like a line that runs across the belly rather than being round or oval. This type of belly button often has a wider opening that extends horizontally, giving it a slit-like appearance.

• Appearance: It appears as a horizontal slit or oval, which can be shallow or moderately deep.
• Causes: This shape can be influenced by body fat distribution and the natural structure of the abdominal muscles.
• Relevance: A horizontal belly button may be altered in cosmetic surgeries to give it a more vertically oriented, oval, or circular appearance, which many people find more aesthetically pleasing.

4. Vertical Belly Button

A vertical belly button is shaped more like a narrow oval or slit that runs up and down the abdomen.

• Appearance: It appears as a vertical line, sometimes referred to as a “T-shape” or “I-shape” navel.
• Causes: This shape can result from genetic factors or how the skin around the umbilicus healed after the umbilical cord was severed. It can also be affected by weight changes and how the skin of the abdomen stretches.
• Surgical Considerations: Vertical belly buttons are often considered aesthetically pleasing, and during procedures like a tummy tuck, surgeons may aim to create a more vertical or oval-shaped belly button to enhance the overall appearance.

5. Round Belly Button

Some belly buttons form a near-perfect circular shape, which is typically deeper but appears round and well-defined.

• Appearance: A round belly button looks like a small circle or “hole” in the abdomen.
• Cosmetic Popularity: This type is often seen as aesthetically pleasing and may be desirable in body contouring surgeries like tummy tucks.
• Surgical Focus: When performing procedures on the abdominal area, surgeons will aim to recreate a naturally round navel, as this is considered youthful and symmetrical.

6. T-Shaped or Inverted T Belly Button

A T-shaped belly button appears when the navel has more than one fold or crease, creating a shape that resembles the letter “T.”

• Appearance: The upper part of the navel forms a horizontal crease, while the lower part may be a vertical fold, forming a T-shape.
• Causes: This shape may occur naturally or be the result of previous abdominal surgery, weight fluctuations, or skin stretching.
• Considerations: In procedures like abdominoplasty or body lifts, surgeons may aim to reduce the appearance of a T-shaped belly button by tightening the skin around the navel and re-sculpting it to create a more defined and streamlined shape.

7. Swirled or Spiral Belly Button

This belly button shape is relatively rare and is characterized by folds of skin that create a swirled or spiral appearance.

• Appearance: It looks like the navel has twisted or spiraled inward, often with folds of skin forming around the central opening.
• Causes: It may be caused by the way the skin around the umbilical scar healed after birth. Genetics can also play a role in the formation of this unique shape.
• Relevance: While some may find this shape distinctive, others may seek surgical correction for a more conventional appearance, especially in the context of body sculpting procedures.

Factors Influencing Belly Button Shape

Several factors influence the shape of the belly button, and while some shapes are purely the result of genetics or the natural healing process, others are influenced by external factors:

1. Umbilical Cord Clamping and Cutting: While the way the umbilical cord is cut does not directly determine the final shape, the healing process can influence the navel’s appearance.
2. Healing Process: The way the umbilical stump heals, whether inward or outward, impacts whether a person has an innie or outie.
3. Body Fat and Abdominal Musculature: The amount of body fat and the structure of the abdominal muscles affect how the skin pulls around the belly button, altering its shape and depth.
4. Pregnancy: In some women, pregnancy can temporarily or permanently alter the shape of the belly button. An innie may become an outie as the abdomen expands, and the skin stretches. After giving birth, the belly button may revert to its original shape, but in some cases, it may remain altered due to changes in skin elasticity or muscle tone.
5. Weight Changes: Significant weight gain or loss can change the appearance of the belly button, as the surrounding skin and fat tissues expand or contract.
6. Hernias: An umbilical hernia can cause the belly button to protrude outward, creating an outie appearance. In these cases, surgery may be necessary to repair the hernia, which could also alter the navel’s shape.

Surgical Procedures for Belly Button Reshaping

Several cosmetic procedures can be performed to alter the shape of the belly button, either for aesthetic reasons or due to medical necessity:

1. Umbilicoplasty: This is a procedure specifically designed to reshape the belly button. It may involve converting an outie to an innie, narrowing the navel, or altering its orientation. The procedure is typically performed under local anaesthesia, and recovery time is relatively short. Umbilicoplasty is often sought after by individuals who are unhappy with the natural shape of their belly button or whose navel has changed due to pregnancy, weight loss, or other factors.
2. Umbilical Lift: The umbilical lift is a procedure described by Mr Nassab and published in the journal PRS Global Open. This is a useful technique to help remove some skin laxity from the upper part of the belly button. This is common after belly button piercings that have stretched after pregnancy.
3. Abdominoplasty (Tummy Tuck): In a full abdominoplasty, the belly button is often repositioned to maintain a natural look after the removal of excess skin and fat from the abdomen. The navel may be reshaped or repositioned to suit the patient’s body proportions.
4. Hernia Repair: Umbilical hernia repair is a medical procedure to correct hernias that occur at the belly button, where part of the intestine pushes through the abdominal wall. Once the hernia is repaired, the surgeon may also reshape the navel for a more aesthetically pleasing result. These are usually performed by general surgeons.

Conclusion

The shape of the belly button is a unique feature of every individual, shaped by a combination of genetic factors, healing processes, and external influences. Whether it’s an innie, outie, or something more unusual like a T-shape or spiral, each belly button has its own story. For those who are unhappy with the shape of their navel, procedures such as umbilical lift or umbilicoplasty offer options to achieve the desired look. Whether for aesthetic reasons or medical necessity, belly button reshaping can be a relatively simple procedure with satisfying results, contributing to an individual’s overall body confidence.