Spatiotemporal changes in the uterus during non-labor contractions

Motivation: Uteroplacental perfusion can be temporarily compromised by non-labor uterine contractions. Goal(s): We performed a quantitative, image-based analysis of the spatiotemporal uterine, myometrium, and placental changes associated with non-labor contractions. Approach: The temporal volumetric changes in the uterus and myometrium, and their correlation with changes in placental volume and T2*, were determined. We also compared volume and T2* changes in placental cotyledons to the surrounding interstitial spaces. Results: Consistent volume decreases in the uterus and myometrium were observed together with decreases in placental volume and T2*. Significantly more deformation and faster decreases in T2* were observed in placental cotyledons compared to the interstitial spaces. Impact: Non-labor contractions consistently correlate with placental volume and T2* decreases with faster changes in cotyledons. Contractions likely eject maternal blood out of the placenta resulting in transient hypoxic stress. Imaging contractions may provide insight into hypoxic stress for the fetus.