- 1 in 100 pregnancies.
- Visualization of only one artery around the fetal bladder.
- Chromosomal abnormalities, mainly trisomy 18, 13 and triploidy, are found in 5% of cases.
- Fetal growth restriction (<5th percentile) occurs in 10% of cases. Stillbirth, usually in association with growth restriction is twice as common as in the general population.
- Abnormalities affecting cardiovascular, skeletal, gastrointestinal, genitourinary and central nervous systems, are found in 20% of cases.
- Detailed ultrasound examination.
- Fetal karyotyping in non-isolated cases.
- Serial scans at 28, 32 and 36 weeks’ gestation to assess fetal growth and well-being.
- Standard obstetric care and delivery.
- In isolated cases the prognosis is normal.
- Isolated: no increased risk of recurrence.
- Part of trisomies: 1%.