Conjoined twins can be diagnosed using standard ultrasound as early as the end of the first trimester. More-detailed ultrasounds and echocardiograms can be used about halfway through pregnancy to better determine the extent of the twins' connection and the functioning of their organs.

If an ultrasound detects conjoined twins, a magnetic resonance imaging (MRI) scan may be done. The MRI may provide greater detail about where the conjoined twins are connected and which organs they share. Fetal MRI and fetal echocardiography assist with planning for care during and after pregnancy.


Treatment of conjoined twins depends on their unique circumstances — their health issues, where they're joined, whether they share organs or other vital structures, and other possible complications.

Monitoring during pregnancy

If you're carrying conjoined twins, you should be closely monitored throughout your pregnancy. You'll likely be referred to a maternal and fetal medicine doctor who specializes in high-risk pregnancy. You may also be referred to other specialists such as:

  • Pediatric surgeons
  • Pediatric urologists
  • Pediatric orthopedic surgeons
  • Plastic surgeons
  • Pediatric cardiologists
  • Pediatric cardiovascular surgeons
  • Neonatologists

Your doctors and others on your health care team learn as much as possible about your twins' anatomy, functional capabilities and prognosis to form a treatment plan for your twins.


A C-section is planned ahead of time, often two to four weeks before your due date.

After your conjoined twins are born, they're fully evaluated. With this information, you and your health care team members can make decisions regarding their care and whether separation surgery is appropriate.

Separation surgery

Separation surgery is an elective procedure done usually a year or more after birth to allow time for planning and preparation. Sometimes an emergency separation may be needed if one of the twins dies, develops a life-threatening condition or threatens the survival of the other twin.

Many complex factors must be considered as part of the decision to pursue separation surgery. Each set of conjoined twins presents a unique set of considerations due to variations in anatomy. Issues include:

  • Whether the twins share vital organs, such as the heart
  • Whether the twins are healthy enough to withstand separation surgery
  • Odds of successful separation
  • Type and extent of reconstructive surgery needed for each twin after separation
  • Type and extent of functional support needed after separation
  • What challenges the twins face if left conjoined

Recent advances in prenatal imaging, critical care and anesthetic care have improved outcomes in separation surgery. After separation surgery, pediatric rehabilitation services are crucial to assist with appropriate skill development through physical, occupational and speech therapies.

If surgery isn't an option

If separation surgery isn't possible or if you decide not to pursue the surgery, your team can help you meet the medical care needs of your twins.

If the circumstances are grave, medical comfort care — such as nutrition, fluids, human touch and pain relief — is provided.

More Information

Coping and support

Learning that your unborn twins have a major medical issue or life-threatening condition can be devastating. As a parent, you struggle with difficult decisions for your conjoined twins and the uncertain future. Outcomes can be difficult to determine, and conjoined twins who survive sometimes face tremendous obstacles.

Because conjoined twins are rare, it may be difficult to find supportive resources. Ask your health care team if medical social workers or counselors are available to help. Depending on your needs, ask for information on organizations that support parents who have children with significant physical conditions or who have lost children.

Preparing for your appointment

If you're pregnant with conjoined twins, you'll be referred to a team of specialists to help guide you and create a treatment plan for your twins. Here's some information to help you get ready and what to expect from your doctor.

What you can do

Before your appointment:

  • Consider taking a family member or friend along. Sometimes it can be hard to remember all the information provided during an appointment. Someone who comes with you may remember something that you missed or forgot.
  • Make a list of questions to ask your doctor. List your questions from most to least important to make the most of your appointment time.

Some basic questions to ask your doctor include:

  • What tests do my twins need?
  • Where are my twins joined and what, if any, body organs do they share?
  • What is the best treatment plan?
  • Is separation an option? What is the likely outcome with separation?
  • How many separation surgeries have you and your team performed, and how many have been successful? How does that compare with the national success rate?
  • What are the alternatives to the treatment approach that you're suggesting?
  • What specialists should be involved in the health care team?
  • Are there any other specialists I should meet with?
  • Where can I find support for my family?
  • Are there printed materials that I can have? What websites do you recommend?
  • If I choose to have more children, is there a chance they may also be conjoined?

Don't hesitate to ask other questions during your appointment.

What to expect from your doctor

Your doctor and health care team will review your conjoined twins' tests and exam results and discuss options with you. Together with your health care team, you can make decisions for your twins' treatment and care.

July 31, 2019
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