Fundal height

Fundal height, or McDonald's rule, is a measure of the size of the uterus used to assess fetal growth and development during pregnancy.

When a tape measure is unavailable, finger widths are used to estimate centimeter (week) distances from a corresponding anatomical landmark.

However, landmark distances from the pubic symphysis are highly variable depending on body type.

In clinical practice, recording the actual fundal height measurement from the palpable top of the uterus to the superior edge of the pubic symphysis is standard practice beginning around 20 weeks gestation.

Measuring the fundal height can be an indicator of proper fetal growth[1] and amniotic fluid development.