title: Robertsonian translocations: an overview of a 30-year experience in a single tertiary medical center in Taiwan.
abstract: BACKGROUND
  Advanced maternal age (AMA) is the most frequent indication for amniocentesis in predicting balanced reciprocal translocations, and abnormal ultrasound findings are indications in predicting unbalanced reciprocal translocations; however, to date, no studies have focused on Robertsonian translocations.
  
  
  METHODS
  A retrospective review was conducted on 16,749 pregnant women who underwent midtrimester amniocentesis between January 1981 and December 2010. Robertsonian translocations were identified in 39 cases.
  
  
  RESULTS
  The percentage of Robertsonian translocations in all amniocentesis cases was 0.23% (39/16,749); 31 were balanced and eight were unbalanced. De novo abnormality occurred in 17 cases, or in 43.6% of all Robertsonian translocations. The two major indications for amniocentesis with a diagnosis of Robertsonian translocations were AMA (41.0%, n = 16) and a parent with abnormal karyotypes (18.0%, n = 7). The highest percentage of Robertsonian translocations was found in parents with abnormal karyotypes (2.8%, 7/252), but neither of the indications were clearly superior for detecting de novo Robertsonian translocations.
  
  
  CONCLUSIONS
  Although AMA is an indication for amniocentesis in approximately two-fifths of cases with Robertsonian translocations, the indication of parent with abnormal karyotypes was more likely to lead to the detection of non-de novo Robertsonian translocations, suggesting that parents with abnormal karyotypes need careful prenatal consultation.
authors.affiliation: Department of Obstetrics and Gynecology, Taipei Veterans General Hospital, Taipei, Taiwan, ROC.
authors.forename: Yi-Wen
authors.initials: YW
authors.lastname: Chang
authors.forename: Ling-Chao
authors.initials: LC
authors.lastname: Chen
authors.forename: Chih-Yao
authors.initials: CY
authors.lastname: Chen
authors.forename: Chang-Ching
authors.initials: CC
authors.lastname: Yeh
authors.forename: Ling-Yi
authors.initials: LY
authors.lastname: Cheng
authors.forename: Yu-Ling
authors.initials: YL
authors.lastname: Lai
authors.forename: Yung-Yung
authors.initials: YY
authors.lastname: Cheng
authors.forename: Wen-Hsun
authors.initials: WH
authors.lastname: Chang
authors.forename: Kuan-Chin
authors.initials: KC
authors.lastname: Wang
authors.forename: Wai Hou
authors.initials: WH
authors.lastname: Li
authors.forename: Pi-Lin
authors.initials: PL
authors.lastname: Sung
authors.forename: Chia-Ming
authors.initials: CM
authors.lastname: Chang
authors.forename: Ming-Jie
authors.initials: MJ
authors.lastname: Yang
authors.forename: Ming-Shyen
authors.initials: MS
authors.lastname: Yen
authors.forename: Kuan-Chong
authors.initials: KC
authors.lastname: Chao
authors.forename: Peng-Hui
authors.initials: PH
authors.lastname: Wang
mesh_terms: D000649:Amniocentesis; D005260:Female; D006801:Humans; D059785:Karyotype; D011247:Pregnancy; D012189:Retrospective Studies; D013624:Taiwan; D014178:Translocation, Genetic