Relation between oligohydramnios and spinal flexion in the human fetus.

Background: Oligohydramnios, a severe reduction in the volume of amniotic fluid, is associated with fetal lung hypoplasia but underlying processes are unclear. Studies in sheep suggest that oligohydramnios may lead to lung hypoplasia by causing increased flexion of the fetal spine, but this has not been demonstrated in the human, which has a different uterine anatomy.

Aims: Our aims were to quantify spinal flexion in the human fetus and to determine the relationship between oligohydramnios and the degree of spinal flexion.