Fetal surgery is a procedure performed on an unborn baby (fetus) in the uterus (in utero) to help improve the long-term outcome of children with specific birth defects. Because these defects often worsen as a fetus develops, fetal surgery done by a team of experts focuses on treating and improving the conditions before birth.

Comprehensive health centers that have fetal surgery expertise and experience can treat many birth defects in utero, including:


Methods for treating these conditions at highly specialized health care centers with fetal surgery expertise include:

  • Fetoscopic endoluminal tracheal occlusion (FETO) for severe CDH
  • In utero open or fetoscopic repair of myelomeningocele, the most severe form of spina bifida
  • Open fetal surgery for SCT resection
  • Open fetal surgery to remove CCAM of the lung
  • Shunt placements
  • Fetal vesicoamniotic shunt (VAS) and fetal cystoscopy for bladder obstruction
  • Fetoscopic laser ablation for TTTS and TAPS
  • Bipolar cord coagulation for TRAP sequence
  • Radiofrequency ablation for fetal tumors
  • Ex utero intrapartum treatment (EXIT)
  • Fetal cardiac intervention
  • Intrauterine blood transfusion
  • Serial amnioinfusions for bilateral renal agenesis and complex renal diseases

Why it's done

Before a baby is born, early intervention using fetal surgery can treat life-threatening birth defects and improve outcomes in some cases. For example, if a baby has been diagnosed before birth with spina bifida, surgeons might perform open fetal surgery or a less invasive procedure using a fetoscope.


Potential risks of the procedure — both the risks to you and those to the unborn baby — should be explained by the doctor. These risks include rupture of the uterus after surgery (uterine rupture), fetal death, operative complications, early labor and potential failure to treat the birth defect.


When done by fetal surgery experts in select babies, this early intervention can have better results than surgery after delivery. This means that children with spina bifida, for example, may be significantly less disabled as they go through life than they would have been if they had surgery after birth.

Clinical trials

Explore Mayo Clinic studies of tests and procedures to help prevent, detect, treat or manage conditions.

Fetal surgery care at Mayo Clinic

March 24, 2021
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