risks of preterm birth, cesarean delivery, low birth weight, low Apgar scores, transfer to the neonatal .... the cord insertion site (arrow) to the edge of the placenta.
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Clinical Letters
Velamentous Cord Insertion With Variable Umbilical Cord Doppler Changes The umbilical cord usually inserts centrally into the placental disk. In approximately 1% to 2% of singleton pregnancies, velamentous cord insertion occurs, with insertion of the cord into the membranes beyond the margin of the placenta. Velamentous cord insertion is associated with risks of preterm birth, cesarean delivery, low birth weight, low Apgar scores, transfer to the neonatal intensive care unit, and perinatal death.1 We present a case of early-onset fetal growth restriction with intermittent abnormal umbilical cord Doppler findings in a patient who was subsequently discovered to have velamentous cord insertion. A 31-year-old woman, gravida 3, para 2, presented for her first sonographic examination at 18 weeks’ gestation by her last menstrual period, at which time the fetus measured 11 days behind. Follow-up at 22 weeks by the last menstrual period revealed a worsening lag of 3 weeks and oligohydramnios. The workup included amniocentesis for karyotype and assessment of viral infection. The karyotype returned as 46,XX, and the infectious workup results were negative. The patient elected for expectant management with serial sonographic examinations for growth, serial Doppler examinations of umbilical artery waveforms, and antenatal testing in the third trimester. By 30 weeks’ gestation, the fetus measured 4 weeks behind, and umbilical artery Doppler assessment revealed elevated systolic-to-diastolic (S/D) ratios (4.79–5.97) as well as pulsatile flow in the umbilical vein (Figure 1A). Close follow-up was recommended. A follow up Doppler examination 1 week later showed normal S/D ratios (1.9– 2.9; Figure 1B).2 At that time, the placental cord insertion was noted to be velamentous (Figure 1, C–E). Although the J Ultrasound Med 2014; 33:2037–2046
fetal size remained less than the 5th percentile for gestational age, there was adequate interval growth, normal subsequent umbilical cord Doppler findings, and an otherwise reassuring fetal status for the remainder of the pregnancy. An elective repeat cesarean delivery was performed at 37 weeks’ gestation, and the patient delivered a female neonate weighing 1815 g with normal cord blood gases and Apgar scores of 7 and 8 at 1 and 5 minutes, respectively. On manual removal of the placenta, a velamentous umbilical cord insertion was confirmed (Figure 1F). The neonate was initially hospitalized for feeding difficulties and low birth weight but was discharged in stable condition on day 19 of life with no evidence of infection or genetic or anatomic malformations. Placental pathologic findings were notable for the velamentous cord, placental weight less than the 10th percentile, and an intervillous thrombus of less than 1% of the placental volume. In the absence of abnormal genetic, anatomic, or infectious abnormalities, the fetal growth restriction and intermittent abnormal Doppler findings were attributed to the velamentous cord. Velamentous cord insertion occurs in 1.5% of singleton gestations, and the 2013 American Institute of Ultrasound in Medicine practice guideline for the performance of obstetric ultrasound examinations recommend that “the placental cord insertion site should be documented when technically possible.”3 Fetal growth restriction (eg, estimated fetal weight
