Pregnancies following pre-conception diagnosis of common aneuploidies by fluorescent in-situ hybridization

Chromosomal aneuploidies contribute considerably to the lowpregnancy rate in in-vitro fertilization (IVF). The objectiveof this experimental work was to explore the possibility ofdetecting common aneuploidies in oocytes by polar body sampling.The study included 45 infertile patients of advanced maternalage participating in an IVF programme. The first polar bodywas removed prior to fertilization or both the first and secondpolar bodies were removed after fertilization and studied byfluorescent in-situ hybridization (FISH) using chromosome-specificprobes for chromosomes X, 18 and/or 13/21. Of 155 oocytes withFISH results, 36 demonstrated chromosomal abnormalities. Of119 oocytes predicted to be free from aneuploidy of chromosomesX, 18 and/or 13/21, 72 were normally fertilized, cleaved andtransferred in 23 treatment cycles, which resulted in two healthydeliveries and three ongoing pregnancies confirmed to be unaffectedby chorionic villous sampling. The method may appear usefulfor the detection of oocytes with common chromosomal aneuploidiesin IVF patients of advanced maternal age. chromosomal aneuploidies/fluorescent in-situ hybridization/human first and second polar bodies/pre-conception/preimplantation genetic diagnosis