Understanding Your Belly Button: Anatomy, Types, Infections (2024)

• Introduction
  • What is the belly button?
• Types
  • Types of belly button
• Odor
  • Why do belly buttons smell?
• Cleaning Tips
  • How to clean your belly button
• Surgeries
  • What surgeries can affect the belly button?
• FAQs
  • Frequently asked questions (FAQs) about belly buttons

What is the belly button?

Your belly button, also called the navel or umbilicus, has no function after birth and is simply a scar or remnant of the umbilical cord that connects you to your mother when you are in the uterus. The blood from the mother's placenta flows through the umbilical cord and provides oxygen and nutrition to a baby during pregnancy, and it is cut and removed after birth, leaving a scar. Read on to learn more about belly button types, infections, and hygiene tips to keep them clean.

Types of belly button

All placental mammals have navels. Marsupials like kangaroos, and egg-laying mammals like platypuses don't have them. In animals, they are flatter, hidden in the fur, and hard to see. In humans, navels come in various shapes and sizes, and the belly button anatomy is determined by how the scar heals and dries after the umbilical cord is cut. Navel shape is just an individual trait, just like how some people have dimples.

Primarily, navel shape may be an innie, which is concave and goes in toward body, or an outie that is convex and protrudes out. An outie forms when the remaining cord stump protrudes instead of sinking inward. Outie is less common than an innie, and is present in only about 10% of the people. Occasionally, an outie belly button may be caused by an umbilical hernia or other medical conditions, but usually it is just a normal variation in shape. Pregnancy can also stretch the navel out, turning an innie into an outie.

Common innie belly button types include:

• Horizontal
• Vertical
• Round
• Oval
• T-shaped
• Light bulb shape

Why do belly buttons smell?

If not cleaned regularly, belly buttons can produce an unpleasant odor.

Other possible reasons why a belly button smells bad include:

• Infections: In a study, researchers found 2368 different species of bacteria living in the navels of 66 individuals, and each person's navel had about 67 types of bacteria. Because the belly button can trap moisture, the skin inside provides an environment in which bacteria can breed, which can lead to bacterial or yeast infection. Along with odor, there may be pain, and a brownish or yellowish discharge. if you have a belly button infection.
• Belly button lint: Dead skin cells, hair, bacteria, and cloth fibers can accumulate in the belly button and produce a bad smell. A study found that hair around the navel may be the culprit for the accumulation of lint. Cleaning out the lint usually removes the other stuff in the navel as well, helping in keeping it clean.
• Omphaloliths: Over time, dead skin cells and sebum can collect in the belly button and create omphaloliths, or navel stones. These are similar to blackheads and can be removed with blunt-ended, non-sharp tweezers rather than being pressed out. Navel stone formation can be prevented by regularly cleaning your navel.
• Epidermoid and pilar cysts: Small cysts can form near the hair follicles (pilar cysts) or on the top layer of the skin (epidermoid cysts). These produce thick keratin mucus. As the cysts grow larger, they can burst and release thick, yellow, foul-smelling discharge.
• Sebaceous cysts: Sebaceous cysts are less common, forming in the sebaceous glands and often becoming infected.
• Patent urachus: A rare cause for a wet and smelly belly button is a patent urachus. Urachus is an early fetal connection with the umbilical cord during development that serves as the fetal bladder until the baby's bladder becomes functional. The urachus scars up and becomes a ligament that runs from behind the navel to the top of the bladder. Rarely, this canal may remain open and urine may leak out of the navel. This condition must be corrected with a surgery.

How to clean your belly button

Gently wipe the inside of the belly button with a cotton swab dipped in saltwater or soapy water. Following a shower, use another clean, dry swab or the corner of a towel or washcloth to gently dry the insides of the belly button to remove all the moisture.

Why do some people not have a belly button?

Some people may not have a belly button for the following reasons:

• Gastroschisis: Gastroschisis is a congenital abdominal wall defect that causes a hole next to the belly button, most commonly seen on the right side. The intestine passes through the hole and develops outside the baby's body within the amniotic fluid during fetal development. In severe cases of gastroschisis, the liver and pancreas may also pass through the hole in the abdominal wall. According to the CDC, 1 out of 2000 babies is affected. Surgery is recommended immediately after birth to increase survival and lower the risk of later complications.
• Omphalocele: Omphalocele is a type of congenital abdominal wall defect where a hole is formed in the belly button. The intestines and other exposed organs are protected by a translucent, membranous sac, which shields the organs from the amniotic fluid that surrounds the infant during pregnancy. The intestines and other internal organs may extend from the abdomen into the umbilical cord during the early stages of pregnancy but usually retreat inside the abdomen by week 11. Omphalocele occurs when the organs do not return to the abdomen. According to the CDC, 1 out of every 4,200 babies in the United States is born with omphalocele. After birth, surgery is done to push back the contents inside.
• Bladder exstrophy: This is a very rare condition in which the fetal bladder is exposed outside the abdomen.
• Cloacal exstrophy: This is a relatively rare condition that occurs when a baby's bladder and a section of the intestines do not form normally and are found outside the body.

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What surgeries can affect the belly button?

Some surgical procedures may result in the loss of the belly button. In some cases, an indentation will remain where the belly button was formerly.

• Breast reconstruction with abdominal tissues: Breast reconstruction surgery performed after a mastectomy may require the use of muscles and tissue from the stomach to rebuild the breast.
• Umbilical hernia repair: An umbilical hernia occurs when there is a weakness in or around the belly button, which allows the intestines to push toward the abdominal wall and form a lump. This may lead to blood flow issues if left unchecked. Surgery is performed to open the area and push the contents back into place.
• Abdominoplasty: Also called a tummy tuck, abdominoplasty removes extra fat from the abdomen and helps to tighten weakening stomach muscles, which makes the stomach look smooth.
• Laparotomy: A laparotomy is a surgical procedure in which an incision is made in the abdominal wall, usually performed when a surgeon knows something is amiss with the abdomen but is unsure of the underlying cause or if a lot of space is needed to perform the surgery.

Can a belly button be created surgically?

A belly button can be created surgically through the following methods:

• Neoumbilicoplasty: is done to create a belly button in people who don't have one. Most techniques require creating thin flaps of skin that are held together by a suture or surgical tie sewn to deeper layers of skin called fascia. This can give the appearance of a belly button.
• Umbilicoplasty: is a surgical technique that improves or reconstructs the appearance of a belly button, which some people elect to have following a pregnancy, abdominal surgery, or liposuction.

Frequently asked questions (FAQs) about belly buttons

What is the purpose of a belly button after birth?

A belly button has no physiological function after birth. It is just the scar and remnant tissue of the umbilical cord. Umbilical cord is the nutritional and waste disposal highway between the mother's placenta and the unborn baby. The cord is severed and clamped after birth, and the stump shrivels up and falls off, typically within 4 weeks after birth, leaving a navel behind.

Why is the belly button important?

Although the belly button has no functional use, it does have some points of importance after birth. It is a useful point of entry for certain medical procedures. The umbilical cord stump may be used as a route if transfusions are required in a newborn, instead of a painful poke into a tiny infant's vein. In later life, it can be used as one of the entry points for laparoscopy to minimize surgical scars.

Belly button abnormalities may serve as an indicator for abdominal or pregnancy problems. The belly button is also a useful anatomical landmark to visually separate the abdomen into 4 quadrants. The navel plays an aesthetic role as well. Although some people may find it distasteful, there are some who find it sexually attractive, and some pierce their belly button and adorn it with jewelry.

Is the belly button connected to anything in adults?

The belly button is a surface scar on the skin tissue and is not attached to any organ beneath in adults. It is attached to the tissue known as fascia beneath, just like the rest of our skin is. The abdominal muscles and fat tissue are beneath the skin, and under these, there is another layer of membrane known as peritoneum that covers the internal organs.

After a baby is born and starts breathing, the blood flow mechanism changes. Blood flow through the umbilical veins and arteries dries up. The blood vessels closest to the navel degenerate and become part of the stomach wall and the interior parts become integrated with the body's circulatory system.

What organ is directly behind the belly button?

The intestines are the internal organs that lie directly behind the navel. The abdominal organs have a protective fat layer called the omentum draped over them. The abdominal cavity is covered by peritoneum, with the muscles, fascia, fat, and subcutaneous tissue forming the other layers beneath the skin.

What is the black stuff in my belly button?

If you have something in your belly button that looks black or dark brown, they are likely to be lint or fuzz, but could also be navel stones. Medically known as omphaloliths, navel stones may form from dead skin, sebum, hair, and other stuff in the navel, and become dry and hard to touch. These can be usually removed with tweezers. Cleaning your navel regularly can prevent accumulation of debris which can become navel stones.

Why does my belly button hurt?

Belly buttons can hurt because of an infection, cyst, or an umbilical hernia. Some women complain of unexplained belly button pain during pregnancy, which usually gets better later in pregnancy. It is not clear why this happens, but it is usually not anything serious. In some, it may be scar tissue from a previous abdominal surgery that gets stretched with the growing abdomen and causes discomfort.

What are the types of belly buttons that can't be pierced?

Although innies and outies are just normal anatomical variations, navel piercing is an advantage for innie, in an innie vs outie belly button contest. A true outie belly button cannot be pierced, because it has protruding scar tissue and scar tissues should not be pierced. The risk for any infection spreading to the internal organs is greater with an outie than an innie, because there are blood vessels in scar tissue. Only the surface skin is pierced in an innie. However, if it is an in-between navel type with a hood of skin tissue, this may be pierced.

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