May all your femurs be long!

Perinatal outcomes after sonographic detection of isolated short femur in the second trimester

“…A short femur length is likely to be a normal variant and is more frequent among certain ethnic groups. 3 Some studies have reported that fetuses of Asian mothers have shorter femurs and those of black mothers have longer femurs compared with fetuses of white mothers. 17 These ethnic differences were not confirmed by other studies.…”

“…Short femur has been associated with fetal growth restriction at the time of the US diagnosis. 1,2 However, a short femur is likely to be a normal variant in a constitutionally small fetus, especially when it is an isolated finding 3 ; however, it may be associated with skeletal dysplasia 4 or could be a marker of aneuploidy. [5][6][7][8] Some studies have reported the association of short femur in the second-trimester US examination with the subsequent delivery of a small-for-gestational age (SGA) neonate, lowbirth-weight (LBW) neonate, and intrauterine growth restriction (IUGR).…”

Midtrimester Isolated Short Femur Length as a Predictor of Adverse Pregnancy Outcome

“…Specifically, in the absence of anatomical or chromosomal malformations, isolated short FL has been associated with intrauterine growth restriction (IUGR), being small for gestational age (SGA) [2,3,9,10,11,12,13,14,15]and preeclampsia [11,16]. Short FL may also be explained constitutionally by ethnic origin and due to inaccurate dating [17,18,19]. …”

Association of midtrimester short femur and short humerus with fetal growth restriction

“…In most affected fetuses with achondroplasia, most commonly nonlethal skeletal dysplasia, obvious limb shortening is not apparent until the early third trimester, at which time sonography often reveals additional findings. Severe skeletal dysplasia is usually suspected on the basis of markedly shortened bones . In fetuses previously screened for aneuploidy and with no evidence of skeletal dysplasia, short femur or humerus may be a normal variant; however, some studies have suggested an association between short femur and FGR …”