title: Risk of recurrence of fetal chromosomal aberrations: analysis of trisomy 21, trisomy 18, trisomy 13, and 45,X in 1,076 Japanese mothers.
abstract: OBJECTIVE
  To evaluate the risk of recurrence of fetal chromosomal aberrations in women who had offspring with numeric chromosomal abnormalities.
  
  
  METHODS
  This collaborative study consisted of 1,076 Japanese women with a history of offspring with trisomy-21, -18, -13, or 45,X. Second-trimester amniocenteses were performed, resulting in 1,248 fetal karyotypes that were analyzed with reference to prior offspring karyotypes and maternal age.
  
  
  RESULTS
  Of the 842 women with trisomy-21 offspring, 10 conceived another such fetus. In 2 women with 3 or more such offspring, parental mosaicism of trisomy-21 was suspected. The incidence of recurrence of trisomy-21 increased with age, and significantly exceeded the incidence of trisomy-21 fetuses in the general population. None of the 170 women with trisomy-18 offspring, and none of the 46 women with trisomy-13 offspring, had another such fetus. Of the 18 women with 45,X offspring, 1 with mos 45,X/46,XX had another such fetus.
  
  
  CONCLUSIONS
  The risk of recurrence of trisomy-21 is affected by maternal age and parental germline mosaicism. The risk of recurrence of trisomy-18 or -13 appears to be much lower than that of trisomy-21. Women who give birth to more than 1 offspring with 45,X should be examined for mos 45,X/46,XX.
authors.affiliation: Department of Obstetrics and Gynecology, Tohoku University School of Medicine, Sendai, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Uehara
authors.forename: N
authors.initials: N
authors.lastname: Yaegashi
authors.forename: T
authors.initials: T
authors.lastname: Maeda
authors.forename: N
authors.initials: N
authors.lastname: Hoshi
authors.forename: S
authors.initials: S
authors.lastname: Fujimoto
authors.forename: K
authors.initials: K
authors.lastname: Fujimori
authors.forename: K
authors.initials: K
authors.lastname: Yanagida
authors.forename: M
authors.initials: M
authors.lastname: Yamanaka
authors.forename: F
authors.initials: F
authors.lastname: Hirahara
authors.forename: A
authors.initials: A
authors.lastname: Yajima
mesh_terms: D000328:Adult; D000649:Amniocentesis; D044466:Asian People / Q000235:genetics*; D002882:Chromosomes, Human, Pair 13; D002887:Chromosomes, Human, Pair 18; D004314:Down Syndrome / Q000235:genetics*; D005260:Female; D005817:Genetic Counseling; D006801:Humans; D007564:Japan / Q000453:epidemiology; D007621:Karyotyping; D008423:Maternal Age; D009030:Mosaicism; D010375:Pedigree; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D012008:Recurrence; D012189:Retrospective Studies; D012307:Risk Factors; D014314:Trisomy / Q000235:genetics*; D014960:X Chromosome