First Birth after Sperm Selection through Discontinuous Gradient Centrifugation and Artificial Insemination from a Chromosomal Translocation Carrier

Introduction. Balanced chromosomal carriers, though usually healthy, are confronted with recurrent spontaneous abortions and malformations in the offspring. Those are related to the transmission of an abnormal, chromosomally unbalanced genotype. We evidenced that the proportion of unbalanced spermatozoa can be significantly decreased through a sperm preparation process called discontinuous gradient centrifugation (DGC). We therefore started offering intrauterine inseminations with this procedure to couples with a male translocation carriers. Case Presentation. We report the case of a 37-year-old man carrying a t(3;10)(q25;p13) reciprocal translocation. He and his partner had had trouble conceiving for ten years and had four spontaneous abortions. DGC in this patient decreased the proportion of unbalanced spermatozoa from 63.6% to 52.3%. They were therefore offered intrauterine insemination with DGC, which eventually led to the birth of a healthy female child carrying the paternal translocation. Conclusion. We showed that translocation carriers could be offered intrauterine inseminations with DGC. Before this, the only two options were natural conception with prenatal diagnosis and termination of chromosomally unbalanced fetuses or preimplantation genetic diagnosis, which is a much heavier and costly procedure. We are currently offering this option through a multicentric program in France, and this is the first birth originating from it. 1. Introduction The prevalence of chromosomal translocation carriers is about 1/500 in the general population. Although these translocations are usually balanced and associated to a normal phenotype, they can lead to recurrent abortions and malformations in the offspring through the fertilization of a genetically unbalanced gamete [1]. Indeed, chromosomal translocation carriers present with a certain proportion of unbalanced gamete, spermatozoa, or oocytes, which varies between patients and which can be evaluated in male patients through fluorescent in situ hybridization (FISH) performed on spermatozoa [2]. However, there is presently no way of selecting chromosomally balanced spermatozoa prior to fertilization. No association has been shown between chromosomal content and cell morphology [3]. However, unbalanced spermatozoa have been shown to have a higher apoptosis rate than their balanced counterpart in Robertsonian and reciprocal translocations as well as in pericentric inversions [4]. This led our team to evaluate the effect of discontinuous gradient centrifugation (DGC) on the proportion of unbalanced spermatozoa.