title: Preimplantation genetic screening for all 24 chromosomes by microarray comparative genomic hybridization significantly increases implantation rates and clinical pregnancy rates in patients undergoing in vitro fertilization with poor prognosis.
abstract: BACKGROUND
  A majority of human embryos produced in vitro are aneuploid, especially in couples undergoing in vitro fertilization (IVF) with poor prognosis. Preimplantation genetic screening (PGS) for all 24 chromosomes has the potential to select the most euploid embryos for transfer in such cases.
  
  
  OBJECTIVE
  To study the efficacy of PGS for all 24 chromosomes by microarray comparative genomic hybridization (array CGH) in Indian couples undergoing IVF cycles with poor prognosis.
  
  
  METHODS
  A retrospective, case-control study was undertaken in an institution-based tertiary care IVF center to compare the clinical outcomes of twenty patients, who underwent 21 PGS cycles with poor prognosis, with 128 non-PGS patients in the control group, with the same inclusion criterion as for the PGS group.
  
  
  METHODS
  Single cells were obtained by laser-assisted embryo biopsy from day 3 embryos and subsequently analyzed by array CGH for all 24 chromosomes. Once the array CGH results were available on the morning of day 5, only chromosomally normal embryos that had progressed to blastocyst stage were transferred.
  
  
  RESULTS
  The implantation rate and clinical pregnancy rate (PR) per transfer were found to be significantly higher in the PGS group than in the control group (63.2% vs. 26.2%, P = 0.001 and 73.3% vs. 36.7%, P = 0.006, respectively), while the multiple PRs sharply declined from 31.9% to 9.1% in the PGS group.
  
  
  CONCLUSIONS
  In this pilot study, we have shown that PGS by array CGH can improve the clinical outcome in patients undergoing IVF with poor prognosis.
authors.affiliation: Center of IVF and Human Reproduction, Institute of Obstetrics and Gynaecology, Sir Ganga Ram Hospital, New Delhi, India.
authors.forename: Gaurav
authors.initials: G
authors.lastname: Majumdar
authors.affiliation: Center of IVF and Human Reproduction, Institute of Obstetrics and Gynaecology, Sir Ganga Ram Hospital, New Delhi, India.
authors.forename: Abha
authors.initials: A
authors.lastname: Majumdar
authors.affiliation: Cytogenetics Laboratory, Center of Medical Genetics, Sir Ganga Ram Hospital, New Delhi, India.
authors.forename: Meena
authors.initials: M
authors.lastname: Lall
authors.affiliation: Center of Medical Genetics, Sir Ganga Ram Hospital, New Delhi, India.
authors.forename: Ishwar C
authors.initials: IC
authors.lastname: Verma
authors.affiliation: Amity Institute of Molecular Biology and Genomics, Amity University, Noida, Uttar Pradesh, India.
authors.forename: Kailash C
authors.initials: KC
authors.lastname: Upadhyaya
keywords: Array comparative genomic hybridization; clinical outcomes; embryo selection; in vitro fertilization; preimplantation genetic screening