C. Wenglinski ¹*, D. Thomas ²
¹Université Libre de Bruxelles, 808 route de Lennik 1070 Bruxelles, Medical school final year Student, Belgium
²Hôpitaux Iris sud, Université libre de Bruxelles 63 rue J Paquot 1050 Bruxelles, MD, Belgium
Case report
Prenatal sonographic investigation brought significant knowledge about fetal venous normal development and its abnormalities. At the sixth week of gestation, the right umbilical vein (RUV) disappears progressively and the left becomes the main duct of blood coming from the placenta. Persistance of this RUV occurs rarely, associated or not with several congenital abnormalities1.
The case we report here seems to be normal with the exception of a RUV making a fusion with the left after a distance of 1,5 cm from the placenta. This 36 years old gravida 1, para 0 healthy woman underwent a third trimester echography at gestational age of 32 weeks. The fetus was small for date, the amniotic index at 40 in favor of oligoamnios. Neither anatomical nor morphological anomaly was described. Marginal insertion of the cord was suspected as well as two nuchal cords.
At 37 weeks, the echography confirmed the slow growth in utero. At the placental end of the cord two arteries and two veins are distincly observed but after a distance of 3 cm both veins are merging together (Figure 1). Doppler flow study confirms the venous nature of this flow coming from the placenta to the ultrasound imaging probe and also in “radiant flow” technology (Figure 2a,b).A caesarean section performed at 38 +6 weeks gave birth to a healthy girl weighing 2710 gr.
The pathological examination confirms these features.
This case is very rare with duplicated umbilical veins on a short segment at their placental end associated with growth retardation. We found two case reports in the literature with persistent caudal portion of the RUV but also multiple congenital anomalies2.
A prospective study4 of 15237 echographies showed 33 cases of RUV persistence, 6 with important congenital anomalies.
Other authors have confirmed the possible association of a RUV with congenital anomalies2,4,5 including the cardiac valves, the kidney or urological system, the brain, asplenia syndrome, trisomy 18 or gastroschisis. These associations occured in isolated pregnancies, in 1-dizygote twin or 1-trizygote triplet but not in multiple monozygotic pregnancies. But normal new-borns were reported in the presence of the same cord veins anomalies3,5. Of course a complete ultrasound examination is mandatory if a RUV is discovered but this is not necessarily an ominous sign and the prognosis of the child can be very good as in our case.
Image 1: confluence of the two veins after 3,2cm. Lateral umbilical cord insertion on the placental plate.