Genetic Analysis of Recurrent Parthenogenesis: A Case Report and Literature Review

The present study reported a case of bilateral salpingectomy for an ectopic pregnancy with recurrent parthenogenesis over two fertilization (IVF) cycles. The first IVF cycle resulted in short-time fertilization. Two cleaved embryos were present after removing the cumulus cells. In the second cycle, intracytoplasmic sperm injection (ICSI) was performed directly and two 6-cell embryos were discovered again prior to the injection. Embryo biopsy, genome amplification, copy number variation (CNV) and single nucleotide polymorphism (SNP) analysis were performed on the two 6-cell embryos of the second cycle. The results of the CNV analysis indicated a genotype of 39,XX,+1,+1,+1,+1,+6q,+6q,+6q,-7p(x1),-10(x1),-13(x0),-15(x0),-17(x1),-18(x1),-19(x1),-20(x1) and the SNP analysis reported that only those chromosomes with one copy had a signal pattern similar to that obtained for an uniparental disomy. Although repeated spontaneous parthenogenesis was observed, the other metaphase II oocytes were fertilized normally after ICSI and the patient became pregnant. A literature review indicated that parthenogenesis may occur in individuals from various populations, and the patients always have a history of either recurrent miscarriages or bilateral tubal obstruction with or without ovarian/fallopian tube surgery. In certain cases, 1 pronucleus (PN) appears and cleaves later and in others, four-to six-cell embryos appear directly.