Which Conditions May Be Treated With Fetal Surgery? Spina Bifida, TTTS and Diaphragmatic Hernia

The anatomy scan is supposed to be the fun appointment. Twenty weeks, a grainy profile, a guess about whose nose the baby has. Then the sonographer goes quiet, measures the same spot three times, and says she would like a specialist to take a look. Later that night, in a hospital parking garage or at a kitchen table, someone types a question they never expected to ask: what conditions does fetal surgery treat, and is this one of them?

The honest answer is shorter than most people expect. Operating on a baby who is still inside the uterus is a young field with a narrow list of proven uses, and a longer list of situations where it is studied, offered selectively, or not offered at all. Three conditions anchor that list: open spina bifida, twin-to-twin transfusion syndrome, and severe congenital diaphragmatic hernia.

This explainer walks through each one, what the procedures actually involve, what the evidence shows and does not show, and the questions worth bringing to the team who knows your pregnancy.

What conditions does fetal surgery treat? The honest short list

Fetal surgery means any procedure performed on a baby, the placenta, or the umbilical cord before birth, while the pregnancy continues afterward. That definition covers everything from a needle passed through the abdomen under ultrasound guidance to an open operation on the uterus itself.

Three conditions carry the strongest evidence and make up most of the work done in specialist centers. Open spina bifida, where part of the spinal cord and nerves develop outside the protective bones of the spine, can be closed before birth. Twin-to-twin transfusion syndrome, a complication of identical twins sharing one placenta, can be treated by sealing the abnormal vessels that let one twin pump blood into the other. Severe congenital diaphragmatic hernia, where a hole in the muscle separating chest from abdomen lets organs push up and crowd the lungs, can be managed with a temporary airway balloon that encourages lung growth. Mayo Clinic describes these as the main established indications.

A second tier exists. Lower urinary tract obstruction, large lung lesions, certain tumors at the base of the spine, amniotic bands wrapped around a limb, and severe fetal anemia are sometimes treated before birth, usually when the alternative is loss of the pregnancy or loss of an organ. These are offered case by case, and the evidence behind them is thinner.

What fetal surgery does not treat is also worth saying plainly. It does not address chromosomal conditions such as Down syndrome, most heart defects, cleft lip, clubfoot, or the many findings that are better managed after a safe delivery. If your search started with a scan result, the first useful question is whether your baby’s finding is on the short list at all, and that is a question for a maternal-fetal medicine specialist, not a search engine.

How fetal surgery actually works: three ways to reach a baby before birth

Picture the uterus as a sealed room with a sleeping occupant, a water supply, and a power cable. Every fetal procedure has to get through the wall without triggering the room to empty early. That single problem shapes how all three approaches are built.

The gentlest route is a needle. Guided by continuous ultrasound, a fine needle passes through the abdominal wall and uterus to reach a vessel in the umbilical cord or a fluid-filled space. This is how fetal blood transfusion for severe anemia is done, and how a small drainage tube, called a shunt, can be placed to relieve a blocked bladder or a fluid-filled lung lesion. Local anesthetic and sometimes light sedation are used, and the pregnant person usually goes home the same day or the next.

The middle route is fetoscopy. A fetoscope is a telescope a few millimeters wide, passed through a small port into the amniotic sac, giving the surgeon a camera view and a channel for instruments such as a laser fiber or a balloon catheter. Twin-to-twin laser treatment and the airway balloon for diaphragmatic hernia both use this approach, and some centers also close spina bifida this way. Regional anesthesia, similar to an epidural, is common.

The most invasive route is open fetal surgery. Under general anesthesia, which also relaxes the uterus and reaches the baby through the placenta, the surgeon makes an abdominal incision, opens the uterus, exposes only the part of the baby that needs repair, operates, and closes the uterus in layers. Medicines that quiet uterine contractions, known as tocolytics, are given around the operation. This is the traditional method for spina bifida closure, and it is the approach studied in the landmark NIH-funded trial discussed below.

Each step up in access brings more precision and more risk, which is why the condition, not preference, decides the route.

Fetal surgery for spina bifida: what closing the defect early can and cannot change

Spina bifida happens in the first weeks of pregnancy, when the neural tube that becomes the brain and spinal cord fails to close fully. The most serious open form, myelomeningocele, leaves a sac of nerves and cord exposed on the baby’s back. According to MedlinePlus, the resulting nerve damage can affect walking, bladder and bowel control, and often comes with fluid buildup in the brain, called hydrocephalus, linked to a downward shift of the hindbrain known as Chiari II malformation.

The idea behind prenatal repair is simple. The exposed cord keeps getting injured by amniotic fluid and friction as the pregnancy continues, and the leak of spinal fluid through the defect is thought to drive the hindbrain shift. Close the back early, and you may limit both. Open repair is typically performed before 26 weeks of pregnancy, per Mayo Clinic, though the exact window varies between centers.

The evidence comes mainly from the Management of Myelomeningocele Study, a randomized trial funded by the NIH. As reported by the National Institute of Child Health and Human Development, babies repaired before birth were less likely to need a shunt to drain brain fluid in their first year, roughly 4 in 10 compared with roughly 8 in 10 of those repaired after birth, and were more likely to walk without aids at 30 months. The hindbrain shift also improved more often.

Those benefits came at a cost that the same trial made clear. Prenatal repair increased preterm birth, with average delivery around 34 weeks, raised the risk of the uterine scar thinning or opening, and committed the mother to cesarean delivery in that pregnancy and future ones. Prenatal repair does not restore normal nerve function below the defect, and many children still need bracing, catheterization, or later orthopedic care. It shifts the odds; it does not rewrite the diagnosis.

Twin to twin transfusion laser surgery: sealing the shared vessels

Identical twins who share a single placenta, called monochorionic twins, almost always share some blood vessels across it. Usually the flow balances out. In twin-to-twin transfusion syndrome, it does not. One twin, the donor, steadily loses blood volume, makes little urine, and ends up with almost no amniotic fluid, pressed against the uterine wall. The other, the recipient, is overloaded, produces excess fluid, and strains its heart. Johns Hopkins Medicine notes that this affects roughly 10 to 15 percent of monochorionic twin pregnancies, and that without treatment advanced cases often end in the loss of one or both twins.

Laser treatment targets the cause rather than the symptoms. Through a fetoscope placed into the recipient’s sac, the surgeon maps the vessels running across the placental surface, identifies every connection that crosses between the twins, and seals each one with laser energy. Excess fluid is drained at the end. The procedure is usually done between about 16 and 26 weeks, when the vessels can be reached and the twins are still too young to be delivered safely, as Mayo Clinic describes.

The alternative older approach, repeatedly draining fluid from the recipient’s sac, relieves pressure but leaves the vessel connections open. Randomized evidence summarized by Johns Hopkins favors laser treatment for survival and for brain outcomes in the surviving twins, which is why it is now the standard offer for moderate to severe stages.

Laser treatment is not risk-free. Membranes can rupture early, labor can start, the procedure can miss a small connection and the syndrome can recur or reverse, and one twin may still be lost despite a technically complete treatment. Staging by ultrasound, including whether the donor’s bladder is visible and how blood flows in the cord, helps the team decide whether to intervene now, watch closely, or deliver.

FETO procedure for diaphragmatic hernia: a balloon that buys the lungs time

The diaphragm is the dome of muscle that separates the chest from the abdomen. In congenital diaphragmatic hernia, part of it never forms, and the stomach, bowel, and sometimes liver slide up into the chest during pregnancy. MedlinePlus Genetics puts the frequency at about 1 in 2,500 newborns. The hole itself is repairable after birth. The real danger is what the crowding does beforehand: the lungs on the affected side, and often both sides, stay small and their blood vessels stay stiff, a combination called pulmonary hypoplasia and pulmonary hypertension.

Fetoscopic endoluminal tracheal occlusion, shortened to FETO, works on a quirk of fetal physiology. Unborn lungs constantly make fluid that drains out through the windpipe. Block the windpipe temporarily, and that fluid builds up, stretches the airways, and stimulates growth. Through a fetoscope passed into the baby’s mouth and down the trachea, the surgeon inflates a small detachable balloon. The balloon is typically placed in the late second or early third trimester and removed a few weeks later, before delivery, by a second fetoscopic procedure or by needle puncture, so the baby can breathe at birth.

This is the newest of the three established indications, and the evidence is still maturing. A multicenter randomized trial in babies with severe left-sided hernias, where the lung-to-head ratio on ultrasound predicted very poor outcomes, found improved survival to discharge with FETO, alongside a higher rate of preterm birth. For moderate cases, the benefit was less clear. Mayo Clinic describes FETO as reserved for the most severe cases for exactly this reason.

Two practical points matter. The balloon has to come out, which means the family needs to stay close enough to a capable center for the removal and for an emergency removal if labor starts early. The hernia itself is still repaired after birth, usually within the first days of life once the baby’s breathing and circulation are stable.

Which other conditions are sometimes treated before birth?

Beyond the three headline conditions, a handful of situations occasionally lead to intervention before birth. Each is rarer, the evidence is weaker, and the offer depends heavily on the individual scan findings.

• Lower urinary tract obstruction. A blockage below the bladder, most often in male babies, backs urine up into the kidneys and leaves too little amniotic fluid for the lungs to develop. A small shunt placed from the bladder to the amniotic sac can relieve pressure. It can restore fluid and protect the lungs, but it does not reliably prevent kidney damage that has already begun.
• Large lung lesions. Fluid-filled cysts in the lung, grouped under the term congenital pulmonary airway malformation, can be drained with a shunt if they grow large enough to compress the heart. Many shrink on their own, so most are simply watched.
• Sacrococcygeal teratoma. A tumor at the base of the spine can steal so much blood flow that the baby’s heart fails. Reducing its blood supply, or in rare cases open removal of the external part, is attempted when heart failure is developing and delivery is too early.
• Amniotic band syndrome. Strands of membrane can wrap around a limb or the cord. Cutting the band fetoscopically may save a limb that is losing blood flow.
• Twin reversed arterial perfusion. One twin without a functioning heart is perfused by the other; sealing the shared cord protects the healthy twin.
• Severe fetal anemia. Blood transfusion through the umbilical vein under ultrasound is well established for anemia from antibodies or infection and is the oldest fetal procedure still in routine use.

Some conditions sit firmly in the research column, including fetal heart valve procedures for critical aortic stenosis. If your baby’s finding is in this group, ask directly whether the proposed procedure is standard, selective, or experimental, and how many cases the center has managed.

Who is usually offered fetal surgery, and who is asked to wait

Eligibility is the point where hope meets criteria, and the criteria exist because fetal surgery asks a healthy person to accept real risk on behalf of someone else. Teams apply them carefully.

For spina bifida, the trial reported by the NIH set the template that most centers still follow. The defect needs to be an open myelomeningocele at a level where repair is expected to help, there must be evidence of the hindbrain shift, the baby’s chromosomes should be normal, and there should be no other major anomaly. The pregnancy must be a singleton. Timing matters: repair is usually done before 26 weeks, after which the balance tips toward waiting for birth.

For twin-to-twin transfusion syndrome, the deciding factor is stage. Early stage disease, where both twins still have a visible bladder and normal cord blood flow, is often watched with scans every week or two, because some cases stabilize. Progression to loss of the donor’s bladder, abnormal flow patterns, fluid buildup in a twin, or signs of heart strain usually prompts laser treatment, provided the gestational age is within the treatable window.

For diaphragmatic hernia, the severity measured on ultrasound and MRI, mainly the size of the remaining lung and whether the liver has moved into the chest, determines whether FETO is discussed. Babies with moderate findings are generally not offered the balloon because the added preterm birth risk is harder to justify.

Across all three, reasons to wait or decline include a short or already-opening cervix, placenta positioned over the entry site, maternal conditions that make surgery or the required medicines unsafe, body habitus that limits access, and gestational age outside the window. Being asked to wait is not a judgment. Often it reflects that delivery followed by standard newborn surgery carries equal or better odds for that particular baby.

Spina bifida, TTTS and CDH compared: a side-by-side summary

The three established indications differ in almost every practical way: what is wrong, who is operated on, how the surgeon gets in, and what is left to do after birth. Seeing them together makes the differences easier to hold in mind.

Feature	Open spina bifida	Twin-to-twin transfusion syndrome	Severe congenital diaphragmatic hernia
What is wrong	Spinal cord exposed through a defect in the back; associated hindbrain shift and fluid on the brain	Unbalanced blood flow between identical twins through shared placental vessels	Hole in the diaphragm; abdominal organs in the chest; underdeveloped lungs
Target of the procedure	The baby’s back	The placenta	The baby’s windpipe
Usual technique	Open uterine surgery; fetoscopic closure at some centers	Fetoscopic laser sealing of vessels	Fetoscopic balloon placement, later removal
Typical window	Before 26 weeks (Mayo Clinic)	About 16 to 26 weeks (Mayo Clinic)	Late second to early third trimester, balloon removed before delivery
Main aim	Reduce need for a brain shunt; improve motor outcome	Stop the transfusion; protect survival and brain development of both twins	Stimulate lung growth before birth
Strength of evidence	Randomized trial (NIH-funded MOMS)	Randomized trial plus long experience	Randomized trial, severe cases only; still maturing
Delivery implications	Cesarean required after open repair, in this and future pregnancies	Delivery mode decided on usual obstetric grounds	Planned delivery at a center able to remove balloon and support breathing
Surgery still needed after birth	Usually no back closure; some still need a shunt	No procedure specific to TTTS	Yes, repair of the diaphragm in the first days of life

One pattern stands out. In two of the three, the operation is not really on the baby at all but on the placenta or airway, and the invasiveness for the pregnant person is lower. Open spina bifida repair remains the exception, and its lifelong obstetric consequences are the reason it draws the most careful counseling.

What are the risks of fetal surgery for the pregnant person and the baby?

Fetal surgery is unusual in medicine because one patient has nothing to gain physically and everything to risk. Ethical practice depends on saying that out loud, and the risks fall into predictable groups.

For the pregnancy, the dominant concern is preterm birth. Any breach of the amniotic sac raises the chance that membranes leak or rupture early, that labor starts, or that the thin inner membrane separates from the outer one. The NIH-reported spina bifida trial found that most babies in the prenatal repair group were born before 37 weeks, and preterm birth carries its own risks for breathing, feeding, and brain development, which partly offsets the gains of the repair. Fetoscopic procedures breach a smaller area, but membrane rupture remains their most common complication.

For the person carrying the pregnancy, open surgery brings the risks of any major abdominal operation: bleeding, infection, blood clots, reactions to anesthesia, and a longer recovery. The medicines used to relax the uterus can cause fluid to collect in the lungs. The uterine incision is placed in the body of the uterus rather than the lower segment used for most cesareans, which is why it is more prone to thinning or opening, and why labor is avoided in all later pregnancies. Placental problems in future pregnancies are also more likely.

For the baby, risks include bleeding, injury during the procedure, worsening of the condition despite treatment, and death. In twin procedures, loss of one twin can harm the survivor through sudden blood shifts, which is one of the reasons laser sealing is preferred over simply draining fluid.

Emotional risk deserves a line of its own. Families often describe the wait between scan and decision as the hardest stretch. Counseling, peer support, and time with a social worker are part of good care, not extras.

What the days and weeks after fetal surgery usually look like

Recovery depends on the route in. After a needle procedure, most people rest for a day and resume ordinary activity with a follow-up scan within a week or two. After a fetoscopic laser or balloon procedure, a hospital stay of one to a few nights is typical, with scans to confirm fluid levels, membrane integrity, and the baby’s heart function before discharge. After open spina bifida repair, the stay is longer, commonly around four to seven days, with intravenous and then oral uterine-relaxing medicines, pain control, and close monitoring for contractions. These ranges reflect what Mayo Clinic and large centers describe as usual, and individual plans vary.

The weeks that follow share a theme: reduced activity and frequent surveillance. Many teams ask the pregnant person to remain within easy reach of the center for the rest of the pregnancy, to avoid heavy lifting, long standing, and sexual intercourse, and to attend ultrasound checks every week or two. After open repair, the scans track amniotic fluid, the thickness of the uterine scar, and the baby’s growth and hindbrain. After laser treatment, they watch for recurrence of the transfusion and for anemia in either twin. After FETO, they measure lung growth and plan the balloon removal.

Some symptoms are expected. Mild cramping, incision soreness, fatigue, and a feeling of tightness are common in the first week. Contractions that come in a regular pattern, fluid leaking, or bleeding are not expected, and the next section covers what to do about them.

Pacing matters for the household as much as the patient. Partners often take on driving, childcare, and work adjustments for months, and families frequently need a temporary place to live near the center. Asking the team early about social work support, lodging programs, and what restrictions actually mean day to day prevents a lot of friction later.

What happens at delivery, and does fetal surgery replace surgery after birth?

Fetal surgery changes the delivery plan more than most families anticipate, and it rarely removes the need for newborn care.

After open spina bifida repair, delivery is by planned cesarean, usually around 37 weeks if the pregnancy has reached that point, and labor is avoided because the scar on the body of the uterus can open under contractions. The baby’s back is typically already closed, so the newborn operation that would otherwise happen in the first days of life is usually not needed. A proportion of children still develop hydrocephalus that needs a shunt, as the NIH-reported trial showed, and all need a lifelong team covering neurosurgery, urology, orthopedics, and rehabilitation. Future pregnancies are managed as high risk with early cesarean delivery.

After laser treatment for twin-to-twin transfusion, delivery timing and mode follow the usual rules for twins sharing a placenta, which generally means planned birth in the late preterm or early term range with continuous monitoring. The twins are examined for anemia, heart function, and, in the months afterward, brain development. No further procedure specific to the syndrome is required.

After FETO, the choreography is tightest. The balloon must be out before the first breath. If it has already been removed electively, delivery proceeds at a center able to provide advanced breathing support, including extracorporeal membrane oxygenation, a machine that oxygenates blood outside the body when the lungs cannot. If labor starts with the balloon in place, the team removes it urgently, sometimes during a cesarean while the baby remains attached to the placenta. The diaphragm is then repaired after birth once the baby is stable, often within the first week.

The thread through all three: fetal surgery is a chapter, not the whole story, and the newborn team is part of the plan from the first consultation.

What people often get wrong about fetal surgery

A field that appears in headlines but touches few families attracts myths. Correcting the common ones is part of informed consent.

Myth: fetal surgery fixes the condition. It does not. Spina bifida repair closes the defect but cannot regrow damaged nerves. Laser treatment stops the transfusion but cannot undo heart or brain injury that has already happened. FETO grows lungs that are still smaller than normal. The evidence shows improved odds, not restored anatomy.

Myth: it is always better to operate early. For many findings, including most lung lesions and early-stage twin-to-twin transfusion, watching is the evidence-based choice because the condition often stabilizes and intervention adds risk without clear benefit.

Myth: the baby is taken out and put back. In open repair, only the part of the baby needing surgery is brought to the uterine opening, and the baby stays attached to the placenta throughout. Fetoscopic procedures do not open the uterus at all.

Myth: a cesarean afterward is optional. After open uterine surgery it is not. The incision site makes labor unsafe in that pregnancy and future ones.

Myth: if a center offers it, the evidence must be solid. Evidence quality varies enormously across indications. A randomized trial supports spina bifida repair and laser treatment; FETO has trial support only for severe cases; several other procedures rest on case series.

Myth: declining fetal surgery is giving up. Postnatal surgery remains the standard route for spina bifida and diaphragmatic hernia, and many families choose it after weighing the maternal risks. That is a legitimate, evidence-supported decision.

Myth: the pregnant person is just the environment. They are a patient undergoing major surgery with lifelong consequences, and their health is weighed equally in every recommendation.

Questions to ask your care team

Consultations about fetal surgery are long, dense, and emotionally loaded, and most people remember a fraction of what was said. A written list helps. These questions are drawn from what families most often wish they had asked.

• Is my baby’s condition one where fetal surgery has randomized trial evidence, selective use, or only early research behind it?
• What specifically do the scans show about severity, and how does that place my baby relative to the cases studied?
• Do I meet the eligibility criteria, and if not, which factor is the barrier and could it change with time?
• What is the expected outcome with standard care after birth, so I can compare like with like?
• What are the risks to me in this pregnancy and in future pregnancies, including the chance of preterm birth and the need for cesarean delivery?
• How many of these procedures does this team perform each year, and what are its own complication rates?
• What will the first week and the following months look like for me, and how close to the center will I need to stay?
• What signs should make me call immediately, and who answers that call at night?
• What newborn care will still be needed, and will the same team follow my child after birth?
• If I decline or am not eligible, what does the care plan for the rest of the pregnancy and delivery look like?
• Is there a social worker, psychologist, or peer family I can speak with before deciding?
• How long do I have to decide, and can I take the information home first?

Two habits make these conversations work better. Bring a second person whose only job is to take notes, and ask the team to write down the numbers they quote so you can look at them again without the pressure of the room. A good team welcomes both.

When to call your doctor

Fetal procedures put the membranes and the uterus under strain, and the complications that matter most announce themselves early. The team that performed the procedure will give specific instructions; these red flags apply after any fetal procedure and also during the watchful weeks before one.

Call the number you were given immediately, or go to the nearest emergency department if you cannot reach them, for any of the following:

• Fluid leaking from the vagina, whether a gush or a steady trickle, which may mean the membranes have ruptured
• Vaginal bleeding of any amount
• Contractions or abdominal tightening that come regularly, more than four to six in an hour, or that become painful
• Severe or worsening abdominal pain, especially pain concentrated over the incision or the uterus
• Fever, chills, or a feeling of being unwell, which may signal infection in the uterus or wound
• A noticeable decrease in the baby’s movements once you have reached the stage where you feel them regularly
• Redness, swelling, discharge, or separation at the incision site
• Shortness of breath, chest pain, or coughing up frothy sputum, which can indicate fluid in the lungs linked to uterine-relaxing medicines
• Pain, swelling, or warmth in one calf, which can indicate a blood clot
• Severe headache, visual disturbance, or sudden swelling of the face and hands

For twin pregnancies under surveillance, a sudden increase in abdominal size, breathlessness when lying flat, or new pelvic pressure can signal rapid fluid buildup and should prompt a same-day call. For pregnancies with a balloon in place, any sign of labor is an emergency, because the balloon must be removed before birth.

No symptom is too small to report when the stakes are this high. Teams would far rather field a call that turns out to be nothing than miss the one that matters.

What matters most when weighing fetal surgery

If one principle should guide a family through this, it is that fetal surgery is a trade, and the terms of the trade differ for every condition. Spina bifida repair trades a lower chance of a brain shunt and a better chance of walking for a near-certain preterm birth and a uterus that will always need cesarean delivery. Laser treatment for twin-to-twin transfusion trades a small procedural risk for a large survival advantage in a condition that is often fatal untreated, which is why it is the least agonizing of the three decisions. FETO trades added preterm risk for lung growth in babies whose outlook without it is poor, and only in those babies.

The quality of the trade depends on honest numbers. Ask for them from the trial literature and from the team’s own experience, and notice when a figure is quoted without a source. The evidence described here comes from randomized trials reported by the NIH and summarized by Mayo Clinic, Johns Hopkins, and the NHS, and even that evidence has limits: follow-up into school age is still accumulating, and outcomes in the trials came from high-volume centers with strict criteria.

The decision also belongs to the right people. The specialist team brings the evidence, the eligibility assessment, and the surgical skill. The family brings their values about risk, about future pregnancies, about distance from home, and about what a good outcome means to them. Neither side can make the decision alone, and a team that pushes rather than informs is a reason to ask for a second opinion.

Finally, remember that the list of conditions is short because the field is honest about what it can prove. That restraint is a feature. It means that when fetal surgery is offered, it is offered because the evidence, not the technology, says it may help.

Frequently asked questions

What conditions does fetal surgery treat most often?

The three most established indications are open spina bifida, twin-to-twin transfusion syndrome, and severe congenital diaphragmatic hernia. Spina bifida is closed before birth, twin-to-twin transfusion is treated by laser sealing of shared placental vessels, and diaphragmatic hernia is managed with a temporary airway balloon. Other conditions, such as bladder outlet obstruction, large lung lesions, and severe fetal anemia, are treated in selected cases where the evidence is thinner and the decision is more individual.

Is fetal surgery for spina bifida better than surgery after birth?

It depends on what is being measured. The NIH-funded randomized trial found prenatal repair reduced the need for a brain shunt and improved the chance of walking independently at 30 months, but it also increased preterm birth and uterine scar complications and requires cesarean delivery in all future pregnancies. Neither option restores lost nerve function. Which balance is better for a specific family is a decision made with a maternal-fetal medicine team after eligibility assessment.

How does twin to twin transfusion laser surgery work?

A thin telescope called a fetoscope is passed through the abdomen into the amniotic sac of the overloaded twin. The surgeon locates every blood vessel that crosses between the twins on the placental surface and seals each one with laser energy, then drains excess fluid. This stops the one-way transfer of blood that was starving one twin and overloading the other. Johns Hopkins Medicine notes it is preferred over repeated fluid drainage for moderate to severe stages.

What is the FETO procedure for diaphragmatic hernia?

FETO stands for fetoscopic endoluminal tracheal occlusion. Through a fetoscope guided into the baby’s mouth and windpipe, a small balloon is inflated to block the airway temporarily. Lung fluid that would normally drain out builds up and stimulates the lungs to grow. The balloon is removed a few weeks later, before birth. A randomized trial supported its use in severe left-sided cases; the hernia itself is repaired after birth once the baby is stable.

What are the risks of fetal surgery?

The leading risk is preterm birth, driven by early rupture of membranes or labor. For the pregnant person, open surgery adds bleeding, infection, clots, anesthesia reactions, fluid in the lungs from uterine-relaxing medicines, and a uterine scar that can thin or open. For the baby, risks include injury, bleeding, worsening of the condition, and death. In twin procedures, loss of one twin can harm the other. Risks are lower with fetoscopic and needle procedures but never zero.

Does fetal surgery mean I need a cesarean?

After open fetal surgery, yes. The incision is made in the body of the uterus rather than the lower segment, and labor could cause it to open, so planned cesarean delivery is required in that pregnancy and every future one. After fetoscopic laser treatment for twin-to-twin transfusion or a needle procedure, the uterus is not opened and delivery mode is decided on the usual obstetric grounds. After FETO, delivery is planned at a center able to remove the balloon and support breathing.

Can every baby with spina bifida have fetal surgery?

No. Centers generally follow criteria set by the NIH-funded trial: an open myelomeningocele with evidence of hindbrain shift, normal chromosomes, no other major anomaly, a single pregnancy, and gestational age before about 26 weeks. Maternal factors such as a short cervix, placenta over the surgical site, certain medical conditions, or body habitus that limits access can also rule it out. Babies who do not qualify are repaired after birth, which remains standard care.

Is there a complete list of conditions fetal surgery treats?

There is no single fixed list, because indications shift as evidence accumulates and some procedures remain experimental. The established core is spina bifida, twin-to-twin transfusion syndrome, and severe diaphragmatic hernia. A selective tier includes lower urinary tract obstruction, large lung lesions, sacrococcygeal teratoma, amniotic band syndrome, twin reversed arterial perfusion, and severe fetal anemia. Heart valve procedures are largely research. Ask the team which category your baby’s finding falls into.

How long is the hospital stay after fetal surgery?

It varies with the procedure. Needle procedures usually involve a day of observation. Fetoscopic laser or balloon procedures typically mean one to a few nights for scans and monitoring. Open spina bifida repair usually requires around four to seven days, with uterine-relaxing medicines and close monitoring for contractions, based on what large centers such as Mayo Clinic describe. Afterward, most teams ask the pregnant person to stay near the center with scans every week or two.

Will my baby still need surgery after birth?

Often, yes. After prenatal spina bifida repair the back is usually closed, but some children still need a shunt for hydrocephalus and most need ongoing specialist care. After FETO, the diaphragm must still be repaired in the first days of life. After laser treatment for twin-to-twin transfusion, no further procedure for the syndrome is needed, though the twins are monitored closely. Fetal surgery is one chapter in a longer care plan, not a replacement for newborn care.

References

• MedlinePlus: Spina Bifida
• MedlinePlus Genetics: Congenital diaphragmatic hernia
• NHS: Spina bifida

This article is for general information only and is not a substitute for professional medical advice. Please consult a qualified doctor about your individual situation.