Maternal-Fetal Medicine · Prenatal Counseling

Duodenal Atresia

Polyhydramnios & Suspected Down Syndrome

Trisomy 21 Association Polyhydramnios Surgical Repair Available

Normal Duodenal Anatomy

Normal stomach and duodenal anatomy diagram

Normally, fluid passes from the stomach into the first part of the small intestine, called the duodenum, and then continues through the bowel.

This pathway is what allows swallowed amniotic fluid to move through the baby's digestive tract before birth.

Duodenal Atresia Before Surgery

In duodenal atresia, the duodenum is blocked. Fluid can collect in the stomach and the first part of the duodenum.

This is why ultrasound may show a "double bubble" and why extra amniotic fluid, or polyhydramnios, can develop.

Duodenal Atresia After Surgery

Duodenal atresia after surgical repair showing reconnected bowel

After birth, pediatric surgeons connect the open ends of the bowel so milk can pass through.

Babies usually need time in the NICU while the intestine starts working and feeding gradually increases.

Pathophysiology

What Is Duodenal Atresia?

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Definition

Congenital complete closure of the duodenal lumen — the first part of the small bowel.

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Ultrasound Sign

Classic "double bubble" — dilated stomach + proximal duodenum filled with fluid.

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Fluid Mechanism

Blockage prevents fetal swallowing absorption → amniotic fluid accumulates (polyhydramnios).

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Incidence

Approximately 1 in 5,000–10,000 live births. Surgical correction is highly effective.

Prenatal Ultrasound Finding

The "Double Bubble" Sign

Two fluid-filled structures separated by the atretic segment. Pathognomonic for duodenal obstruction on prenatal ultrasound.

Maternal-Fetal Risk

Polyhydramnios: Why It Matters

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Preterm Labor

Uterine overdistension increases risk of preterm contractions and PROM.

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Malpresentation

Excess fluid allows fetal movement, increasing risk of breech or transverse lie.

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Monitoring

Serial ultrasounds to track amniotic fluid index (AFI) and maximum vertical pocket.

Genetic Considerations

Down Syndrome Association

~40%

of duodenal atresia cases
associated with Trisomy 21

High

prevalence of congenital
heart defects in both conditions

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Recommended Testing

Amniocentesis for karyotyping & chromosomal microarray if not yet performed.

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Fetal Echocardiography

Mandatory — congenital heart defects are prevalent in both Down syndrome and duodenal atresia.

Counseling Framework

Key Counseling Domains

Domain	Clinical Action	Priority
Prenatal Monitoring	Serial ultrasounds for AFI; monitor for preterm labor	Ongoing
Genetic Confirmation	Amniocentesis for karyotype & microarray	Prompt
Cardiac Evaluation	Fetal echocardiogram — mandatory	Prompt
Delivery Planning	Tertiary center with Level III/IV NICU & pediatric surgery	Planned
Family Counseling	Genetics consult; social work support	Supportive

Postnatal Management

Care Sequence After Birth

Immediately at Birth

Gastric decompression — Replogle or NG tube to continuous suction; prevents emesis and aspiration.

Hours 1–24

IV fluids for resuscitation; correct electrolyte imbalances. Postnatal echocardiogram to evaluate cardiac anatomy.

Once Medically Stable

Surgical repair — duodenoduodenostomy (bypass) or web resection. Not a Day 1 emergency; cardiac clearance takes priority.

Postoperative

Gradual enteral feeds; NICU monitoring. Duration depends on associated anomalies and prematurity.

Prognosis & Outcomes

Long-Term Outlook

>90%

long-term survival for
isolated duodenal atresia

Cardiac

anomaly severity is the
primary prognostic driver

High

surgical success rate
for bowel repair

Surgical repair of the bowel obstruction is highly effective. Overall prognosis is primarily determined by the presence and severity of associated cardiac anomalies and complications of prematurity.

Our Commitment to Your Family

You Are Not Alone in This

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Close Monitoring

Serial ultrasounds and specialist visits throughout your pregnancy.

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Expert Team

MFM, neonatology, pediatric surgery, genetics, and cardiology — coordinated care.

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Open Dialogue

Questions are always welcome. We will revisit your care plan at every visit.

ACOG · SMFM · Evidence-Based Prenatal Counseling | Atlanta Perinatal Associates