Ultrasound femur length as a means of assessing gestational age amongst Nigerians.

Foetal femur length values have been established with ultrasound amongst Nigeria pregnant women between 14-40 weeks of gestation. The growth of the femur describes an asymptotic curve similar to the one for biparietal diameter. A linear mathematical model was found suitable to describe the relationship between the femur length and gestational age and our values have been compared with those obtained from similar previous studies. The value of femur length data in gestational age assessment foetal weight estimation, and in the identification of foetal limb deformities is discussed.