Objective: To determine the effects of maternal left lateral, right lateral, and supine positions during labor on fetal oxygen saturation measured by pulse oximetry.
Methods: Fetal oxygen saturation measured by pulse oximetry was obtained in 15 laboring women randomly and successively adopting left lateral, supine, and right lateral positions for 10 minutes each. Repeated measures analysis of variance was used for statistical analysis.
Results: Changes in fetal oxygen saturation were observed in different maternal positions. The supine position was associated with a lower fetal oxygen saturation than the left lateral position. One supine hypotensive syndrome occurred and was associated with a drop in fetal oxygen saturation.
Conclusion: Maternal supine position during labor is associated with a lower fetal oxygen saturation than the left lateral position.