title: [Clinical analysis of 21 cases with short fetal femur in the third trimester].
abstract: Objective:To analyze the clinical features and to explore the etiology of short fetal femur during the third trimester.Methods:From January 2010 to June 2016, 21 singleton pregnancies with short fetal femur detected by ultrasonography during the third trimester were referred to the Chinese PLA General Hospital. Clinical data were collected, karyotype or single nucleotide polymorphism microarray was carried out to detect chromosomal abnormalities, and FGFR3 c.1138G>A mutation detection was carried out to detect achondroplasia (ACH) via invasive procedure, respectively. The deviation of femur length from the mean value of the gestational age in ultrasonography was expressed as theZ-score. The difference between ACH and isolated short femur (ISF, in the absence of associated structure abnormality or genetic abnormality) was then explored.Results:In the 21 fetuses, 11 had abnormal genetic test results(52%, 11/21), including 9 cases of ACH, 1 case of Ellis-van Creveld Syndrome and 1 case of Pallister-Killian syndrome. In the 10 ISF fetuses (48%, 10/21), 3 cases were fetal growth restriction, 1 was normal small for gestational age infant and 6 cases were unexplained. The medianZ-scores for 9 cases of ACH and 10 cases of ISF in the third trimester were -5.04, -3.20, respectively. The short femur in ACH was more severe than in ISF (P=0.005) in the third trimester.Conclusions:The etiology of short fetal femur is complicated, including skeletal dysplasia, chromosomal abnormality, fetal growth restriction, as well as normal variants during fetal development. Genetic test should be considered during the antenatal consultation.
authors.affiliation: Department of Obstetrics and Gynecology, Chinese PLA General Hospital, Beijing 100853, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Ren
authors.forename: Y Q
authors.initials: YQ
authors.lastname: You
authors.forename: H H
authors.initials: HH
authors.lastname: Zhou
authors.forename: L X
authors.initials: LX
authors.lastname: Wang
authors.forename: H
authors.initials: H
authors.lastname: Xu
authors.forename: R B
authors.initials: RB
authors.lastname: Li
authors.forename: S J
authors.initials: SJ
authors.lastname: Wang
authors.forename: X X
authors.initials: XX
authors.lastname: Xie
authors.forename: Y G
authors.initials: YG
authors.lastname: Meng
authors.forename: Y P
authors.initials: YP
authors.lastname: Lu
mesh_terms: D000130:Achondroplasia; D001848:Bone Diseases, Developmental / Q000000981:diagnostic imaging* / Q000235:genetics; D002869:Chromosome Aberrations; D025063:Chromosome Disorders; D002881:Chromosomes, Human, Pair 12; D005260:Female; D005269:Femur / Q000002:abnormalities* / Q000000981:diagnostic imaging* / Q000196:embryology; D047109:Fetal Development; D005317:Fetal Growth Retardation / Q000000981:diagnostic imaging* / Q000209:etiology; D005333:Fetus; D005865:Gestational Age; D006801:Humans; D007621:Karyotyping; D046228:Microarray Analysis; D020641:Polymorphism, Single Nucleotide; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D011263:Pregnancy Trimester, Third; D051498:Receptor, Fibroblast Growth Factor, Type 3 / Q000378:metabolism; D016216:Ultrasonography, Prenatal
chemical_list: C496365:FGFR3 protein, human; D051498:Receptor, Fibroblast Growth Factor, Type 3
keywords: Congenital abnormalities; Femur; Pregnancy trimester, third; Receptor, fibroblast growth factor, type 3; Ultrasonography, prenatal