Sirenomelia in a monoamniotic twin: a case report
Mohamed N Akl1, Abdelaziz A Saleh
1Department of Obstetrics and Gynecology, Michigan State University, Hurley Medical Center, Flint, Michigan 48503, USA. maklmd@aol.com
The Journal of Reproductive Medicine
|April 1, 2006
Summary
Sirenomelia, a rare congenital fusion of lower limbs, can be diagnosed early in twin gestations without oligohydramnios. This absence of amniotic fluid allows fetal movement, improving prenatal diagnosis and infant respiratory outcomes.
Area of Science:
- Perinatology
- Medical Genetics
- Congenital Malformations
Background:
- Sirenomelia is a rare congenital malformation involving fusion of the lower extremities, typically associated with renal agenesis and absent bladder.
- Oligohydramnios, a common complication, usually manifests early in pregnancy for affected fetuses.
Observation:
- A case of sirenomelia in one twin of a dichorionic-diamniotic twin gestation was diagnosed prenatally at 18 weeks.
- The affected infant, born at 34 weeks, exhibited good respiratory condition and survived for 5 days, succumbing to nonpulmonary causes.
Findings:
- Absence of oligohydramnios in monoamniotic twins facilitates fetal movement, enhancing ultrasound visualization of organs.
- Early prenatal diagnosis of sirenomelia is aided by the absence of oligohydramnios, allowing for better management strategies.
Implications:
- The lack of oligohydramnios in monoamniotic twins may improve the respiratory status of infants with sirenomelia, potentially delaying mortality.
- This case highlights the importance of considering twin gestation and amniotic fluid status in the prenatal diagnosis and management of sirenomelia.
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