Re: 'Single umbilical artery-right or left? Does it matter?' by Blazer et al.
We read with interest the article of Blazer et al. (1997) on the subject of single umbilical artery in the fetus. The authors report their experience with 46 cases of prenatally diagnosed single umbilical artery and state that 'this is the first prospective study of a large number of consecutive pregnancies in which the side of the existing artery was identified'. Furthermore, in their Introduction, the authors mention that they were not able to find in the peer reviewed literature a study that specifically addressed the issue of the side of a single umbilical artery and its possible implications.
We would like to refer the authors to our study entitled 'Single umbilical artery: does it matter which artery is missing?' published in the American Journal of Obstetrics and Gynecology in 1995 (Abuhamad et al., 1995). In this study, the side of the missing artery was determined prospectively in 77 fetuses with a single umbilical artery. The left artery was more commonly absent than the right one, and the presence of cytogenetic and complex abnormalities (more than one organ system) occurred exclusively in association with the absence of the left artery.
It is unclear how our report was missed by the authors' literature search, especially that it