Final answer:
Excessive fundal height can be caused by polyhydramnios, multiple pregnancies, and large fetuses. Conditions such as gestational diabetes and macrosomia can contribute to an overly large fetus and consequently, a higher fundal height.
Step-by-step explanation:
Excessive fundal height, which is the measurement from the top of the uterus to the pubic bone, can be caused by several factors in pregnancy. One possible cause is excessive amniotic fluid, known as polyhydramnios. This condition can occur when the fetus is unable to swallow or absorb enough fluid, resulting in an accumulation of amniotic fluid. Another possible cause is multiple pregnancies, such as twins or triplets, which can lead to larger than average fundal height. Lastly, an overly large fetus, which may be caused by conditions such as gestational diabetes or macrosomia, can also result in fundal height exceeding expectations.
For example, a fetus with uncontrolled gestational diabetes may receive excessive glucose from the mother, causing it to grow at a faster rate than normal. This can lead to a larger than expected fundal height measurement.