ModifiedAmbetter NevadaPolicy CP.MP.129

Fetal Surgery in Utero for Prenatally Diagnosed Malformations

Defines medical necessity criteria, coding implications, and exclusions for in‑utero fetal surgery procedures for specific prenatally diagnosed fetal malformations for members of Ambetter Nevada (Centene-affiliated plans). Affects providers performing fetal interventions and those requesting authorization.

Policy Summary

PayerAmbetter Nevada

PolicyFetal Surgery in Utero for Prenatally Diagnosed Malformations

Policy CodePolicy CP.MP.129

Change TypeMaterial revisions to criteria and coding

Effective Date

Next Review Date

Key ActionObtain prior authorization and note that repeat in‑utero fetal surgery procedures require secondary review by the plan.

SourceLink

POLICY UPDATE CHANGES

Added 'D. Placement of a thoraco-amniotic shunt for pleural effusion with or without secondary fetal hydrops' to criteria set I.

Criteria for myelomeningocele (I.G) updated to require confirmation of hindbrain herniation on fetal MRI and specified gestational age window 19 0/7 to 25 6/7 weeks and singleton pregnancy.

Added FETO criteria for CDH: severe left-sided CDH, observed-to-expected lung-to-head ratio <25%, gestational age ≤ 30 weeks.

Removed specific degree requirement for severe kyphosis and removed prior maternal BMI contraindication for myelomeningocele criteria.

Added CPT code 59072 (fetal umbilical cord occlusion) to coding list.

7Medically necessary indications listed

19–25wMyelomeningocele GA window

<25%o/e LHR threshold for FETO

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Medically Necessary Indications and Coverage Guidance

Medically Necessary Indications

Covered when the specific indication AND the listed subcriteria are met

I.A Sacrococcygeal teratoma (SCT)

Fetuses with high-risk SCT and hydrops developing at a gestational age earlier than appropriate for delivery and neonatal care (e.g., 28–32 weeks gestation)
Contraindications absent: Does not have any of the following contraindications: Type III or IV Altman-type tumors; severe placentomegaly; maternal cervical shortening.

I.B Lower urinary tract obstruction: Lower urinary tract obstruction without multiple fetal anomalies or chromosomal abnormalities: urinary decompression via vesico-amniotic shunting.

I.C CPAM and extralobar BPS: Congenital pulmonary airway malformation (CPAM) and extralobar bronchopulmonary sequestration (BPS) with high-risk tumors: resection of malformed pulmonary tissue, or placement of a thoraco-amniotic shunt.

I.D Pleural effusion with/without hydrops: Placement of a thoraco-amniotic shunt for pleural effusion with or without secondary fetal hydrops.

I.E Twin-twin transfusion syndrome (TTTS)

Option 1: Amnioreduction.
Option 2: Fetoscopic laser ablation, with or without amnioreduction, when pregnancy is between 16 and 26 weeks gestation.16–26 weeks

I.F TRAP sequence: Twin-reversed-arterial-perfusion (TRAP) sequence: ablation of anastomotic vessels of the acardiac twin (e.g., laser or radiofrequency ablation).

I.G Myelomeningocele repair

Singleton pregnancy.
Upper boundary of myelomeningocele located between T1 and S1.
Evidence of hindbrain herniation confirmed on fetal MRI.
Gestational age between 19 0/7 weeks and 25 6/7 weeks.19 0/7–25 6/7 weeks
Exclusions: None of the following are present: severe kyphosis; risk of preterm birth (e.g., short cervix or previous preterm birth); placental abruption; previous hysterotomy in the active uterine segment.

I.H FETO for CDH

Severe left-sided congenital diaphragmatic hernia (CDH).
Severe pulmonary hypoplasia defined as an observed-to-expected lung-to-head ratio (o/e LHR) of less than 25%.o/e LHR <25%
Gestational age ≤ 30 weeks.≤30 weeks

Open or endoscopic fetal surgery is not supported for a number of specific fetal conditions because current evidence and clinical guidance do not demonstrate benefit or acceptable risk profiles for those indications. Examples listed in the policy include surgery for heart block, procedures to relieve pulmonary valve or aortic obstruction, and interventions for tracheal atresia or stenosis. Other unsupported procedures explicitly named are repair of cleft lip and palate, in‑utero stem cell transplantation, in‑utero gene therapy, and the amnioexchange procedure for gastroschisis. These exclusions reflect the policy’s intent to limit in‑utero surgical interventions to indications with sufficient evidence and established clinical protocols.

The policy states that current evidence does not support use of in utero fetal surgery for several listed indications. Specifically, fetal surgery is considered unsupported for surgery for heart block, pulmonary valve or aortic obstruction, tracheal atresia or stenosis, cleft lip and palate, in‑utero stem cell transplantation, in‑utero gene therapy, and amnioexchange for gastroschisis. This reflects the plan’s review of available literature and consensus that these procedures lack sufficient proven benefit to merit coverage as medically necessary.

This clinical policy is provided as a medical necessity guide to assist in coverage decisions and administration of benefits; it is not a contract and does not guarantee payment or clinical outcomes. Coverage determinations remain subject to the member’s applicable coverage documents, including evidence of coverage, certificates, and contracts, as well as state and federal requirements and Health Plan‑level administrative policies. The Health Plan may change, amend, or withdraw this clinical policy at any time, and providers must confirm plan‑level prior authorization and other administrative requirements before proceeding with care.

Referenced Procedure and Billing Codes

Referenced CPT CodesCPT

59001	Amniocentesis; therapeutic amniotic fluid reduction (includes ultrasound guidance).
59076	Fetal shunt placement, including ultrasound guidance.
59897	Unlisted fetal invasive procedure, including ultrasound guidance, when performed.
59072	Fetal umbilical cord occlusion, including ultrasound guidance

Referenced HCPCS S‑codesHCPCS

S2401	Repair, urinary tract obstruction in the fetus, procedure performed in utero.
S2402	Repair, congenital cystic adenomatoid malformation in the fetus, procedure performed in utero.
S2403	Repair, extralobar pulmonary sequestration in the fetus, procedure performed in utero.
S2404	Repair, myelomeningocele in the fetus, procedure performed in utero.
S2405	Repair of sacrococcygeal teratoma in the fetus, procedure performed in utero.
S2409	Repair congenital malformation of fetus, procedure performed in utero, not otherwise classified.
S2411	Fetoscopic laser therapy for treatment of twin-to-twin transfusion syndrome.

Observed-to-expected lung-to-head ratio (o/e LHR)

Observed-to-expected lung-to-head ratio (o/e LHR)<25%

Use in FETO for severe left-sided CDHRequired threshold for severe pulmonary hypoplasia is o/e LHR <25%

Gestational age relevanceo/e LHR threshold applied when gestational age is ≤30 weeks for FETO candidacy

Gestational age for myelomeningocele repair

Myelomeningocele repair gestational age window19 0/7 to 25 6/7 weeks

Singleton pregnancy requirementProcedure criteria require singleton pregnancy in addition to GA window

Authorization, Documentation, and Claims Guidance

Prior Authorization

Prior Authorization and Secondary Review

Prior authorization is required for in-utero fetal surgery procedures. Providers must obtain plan-level authorization prior to scheduling or performing these services. Repeat in-utero fetal surgery procedures require secondary review by the Health Plan before authorization will be considered.

Repeat procedures require secondary review
Obtain prior authorization before scheduling

Prior Authorization

Prior Authorization and Medical Necessity

This clinical policy is a guide to medical necessity and does not itself guarantee coverage. Providers must confirm specific plan-level prior authorization requirements and benefit coverage with the member's Health Plan prior to providing services.

Policy provides medical necessity criteria but is not a guarantee of payment
Verify member benefits and authorization requirements with the Health Plan

Background on Maternal-Fetal Surgery

Maternal‑fetal surgery encompasses both open fetal surgery and fetoscopic (minimally invasive) approaches, and these interventions carry significant maternal and fetal risks. They are generally performed at specialized fetal therapy centers with multidisciplinary teams because procedures can increase the risk of maternal morbidity and frequently result in prematurity or other neonatal complications. Indications for intervention vary by anomaly and gestational age; for some conditions (for example, severe congenital diaphragmatic hernia or myelomeningocele) specific imaging findings and gestational age windows are required to consider intervention. Given the complexity and evolving evidence base, repeat procedures require secondary review and the policy emphasizes that only interventions supported by sufficient evidence and clear criteria are considered medically necessary.

Procedural Definitions

Open fetal surgery

DefinitionOpen fetal surgery involves performing a hysterotomy, partially exteriorizing the fetus to expose and correct the abnormality, then returning the fetus to the uterus to continue development until delivery.

Indication severityConsidered when the fetal condition is life threatening and the intervention is felt to be the only option for fetal survival.

Setting requirementShould be offered only at facilities with specialized expertise, multidisciplinary teams, and intensive care capabilities.

Fetoscopic (minimally invasive) fetal surgery

DefinitionFetoscopic (minimally invasive) fetal surgery uses small fiberoptic telescopes and instruments introduced through small uterine openings to correct congenital malformations without major incisions or removing the fetus from the womb.

Clinical advantage