Two-dimensional sonographic assessment of maximum placental length and thickness in the second trimester: a reproducibility study.

Objectives: To determine the most reproducible method for the sonographic measurement of placental length.

Methods: A prospective study of women with singleton pregnancies who underwent sonographic measurement of placental dimensions during mid-gestation. Two sonographers independently determined placental length using three different approaches (linear, curve-linear and panoramic) and placental thickness.