Foetal biometry in polyhydramnios: Does femur length fall behind?

Area of Science:

• Obstetrics and Gynecology
• Fetal Medicine
• Maternal-Fetal Medicine

Background:

• Polyhydramnios, characterized by excessive amniotic fluid, can impact fetal development.
• Understanding fetal growth patterns in polyhydramnios is crucial for accurate diagnosis and management.

Purpose of the Study:

• To identify specific fetal growth patterns in singleton pregnancies complicated by polyhydramnios.
• To analyze pregnancy outcomes in relation to observed fetal growth features.

Main Methods:

• Evaluation of 108 singleton pregnancies with polyhydramnios.
• Analysis of changes in biparietal diameter (BPD), abdominal circumference (AC), and femur length (FL) percentiles from the second to third trimester.
• Comparison of growth features between overgrown and non-overgrown fetal groups.

Main Results:

• A significant increase in BPD and AC percentiles was observed from the second to third trimester (p = 0.023 and 0.05, respectively).
• A significant decrease in FL percentiles was noted in the third trimester compared to the second (p = 0.006).
• In overgrown fetuses (n=52), a lower FL/BPD ratio was found (p < 0.001), with more cases below 71 (p = 0.05), without evidence of skeletal dysplasia.

Conclusions:

• Polyhydramnios is associated with distinct fetal growth alterations, including increased BPD and AC, and decreased FL percentiles.
• Overgrown fetuses in polyhydramnios exhibit shorter femur lengths and lower FL/BPD ratios, independent of skeletal dysplasia.