With symmastia, your breasts cross the midline of the chest. Your breasts or breast implants appear to merge, leaving no space between them.

If you have symmastia, your cleavage may present as:

  • an empty web of skin between your breasts
  • a web of skin, fat, and other tissue between your breasts
  • an abnormal arrangement of collagen fibers in the breast tissue

There are two types of symmastia. The first is congenital, meaning you’re born with it. This type is very rare.

The second is iatrogenic, or acquired. This type is a complication of breast surgery, but it’s also quite rare.

Symptoms are mainly cosmetic. But acquired symmastia can sometimes cause discomfort or pain in the breasts.

Keep reading to learn more about what causes symmastia and when to consider treatment.

It isn’t clear what causes congenital symmastia.

Acquired symmastia is usually a complication of breast reconstruction or augmentation surgery, particularly when it involves oversized implants.

Following breast augmentation surgery, constant pressure or too much dissection of the midline can cause a capsular pocket to develop. When this happens, one or both implants can shift out of place and drift toward the center of your chest.

Although you might notice this right after your surgery, it’s possible that it won’t become obvious until postsurgical swelling goes down.

You may be more likely to develop symmastia if:

  • your surgeon used implants that are too big or too wide for your body
  • you have preexisting deformities of the chest wall
  • your implants were positioned incorrectly or using poor technique

The only potential remedy for either form of symmastia is surgery.

Congenital symmastia

Treatment of congenital symmastia is complicated. Because it’s so rare, there are few case reports for doctors to review. It’s not as simple as performing traditional breast reduction surgery because it’s not a problem of size, but of structure.

In the case of congenital symmastia, it’s important to put off surgery until your breasts have reached maturity and your weight is fairly stable.

Though it’s difficult, congenital symmastia can sometimes be effectively treated with a combination of liposuction, skin fixation to sternum, and postoperative intermammary compression.

Just before the procedure, your surgeon will carefully mark your skin for guidance during surgery. Then you’ll be given general anesthesia and a breathing tube.

Removal of excess tissue between the breasts can be accomplished through surgical resection or with liposuction.

An incision will be made where your breasts meet your chest. The actual surgical procedure from there will vary according to the particulars of your symmastia.

After surgery, you may be required to wear a compression bra for several months. This is a special type of bra that creates compression in the midline while supporting the breasts.

Acquired symmastia

Acquired symmastia is easier to correct than congenital symmastia. The technique will vary depending on the positioning of your breasts and implants and how your inner tissues have healed.

Surgery will likely involve removing scar tissue, repairing the pocket, and repositioning or replacing implants, potentially with a smaller-sized implant. Permanent internal sutures will help hold breasts and implants in the proper position.

Complications of any surgery may include a bad reaction to anesthesia, bleeding, and infection at the surgical site. This particular surgery can also lead to:

  • asymmetrical breasts
  • irregularities in contouring
  • scarring

Symmastia may not pose any risks to your health.

But if you’ve had breast reconstruction or breast implants, it’s important to consult with your surgeon as soon as possible. A thorough evaluation can help determine if there are additional problems that need to be addressed. If breast implants continue to shift, it may make symmastia more pronounced and harder to correct later on.

No two cases of symmastia are exactly alike, and surgery to repair it differs from person to person.

The first thing to consider is whether corrective surgery is medically necessary. That’s why you should begin with a thorough medical evaluation. If surgery isn’t medically necessary, it’s a question of cosmetics.

If the appearance of your breasts bothers you a great deal or it’s becoming a quality of life issue, it’s worth investigating your options so you can make an educated decision.

First, consult with your previous surgeon to learn more about why it happened in the first place. Then:

  • Get a second opinion, or maybe even a third.
  • Speak with surgeons who have performed this type of corrective surgery before. Find out why they recommend a particular technique and what their success rate is.
  • Ask questions about what you can expect during recovery and what the potential risks are.
  • Check with your health insurer to see if you’re covered for this procedure.

Symmastia can be successfully treated. But the decision to have corrective surgery is an intensely personal one. Once you get a few professional opinions, you’ll be in a better position to decide what’s right for you.