Objectives To examine the outcome of fetuses diagnosed with short femur length at the time of the routine anomaly scan.

Methods This was a retrospective review of 58 pregnancies referred to fetal medicine department with fetal femur length below the 3^rd centile between gestations 18-22 weeks at Heart of England NHS Foundation Trusts. The time period was from August to July 2010[36months]. The patients with Multiple pregnancies and with PPROM <20weeks were excluded. The policy of first trimester NT screening

was not in place during the study period.

Results Out of the 58 cases identified, 9 were excluded. Detailed ultrasound examination showed associated fetal abnormalities in 29 out of 49 cases, leaving 20 cases of isolated short femur.

IUGR with abnormal uterine artery Doppler findings and delivery before 37 weeks occurred only in 3 cases.

75% had constitutionally small babies. There was no association with PET, PTL. IUD.

Those with normal UAD were at low risk for these complications.

Conclusions The findings of isolated short femur at 18-24 weeks is unlikely to be due to aneuploidy. Severe IUGR associated with high mortality occurs in 40% making Uterine Artery Doppler evaluation a useful tool.

Detailed ultrasound examination is essential, as 50% of cases in our study had other anomalies. Once isolated, UAD helps in triaging the cases.