(P27-005-25) Fetal Kidney Length Is Associated With Maternal Plasma Provitamin A Carotenoids During Pregnancy

Objectives: Despite the importance of vitamin A (retinol) in kidney development, the impact of compounds with pro-vitamin A activity (α-carotene, β-carotene, & β-cryptoxanthin) on kidney size has not been examined. This study investigates the association between maternal provitamin A carotenoid status and fetal and infant kidney measurements.

Methods: An IRB-approved study enrolled pregnant women at 18-20 weeks gestation. Fetal and Infant kidney measurements were recorded by ultrasound during anatomy scan & within 48-72 hours after birth. Maternal blood samples were collected between 24-28 weeks gestation (n=79) & at the time of delivery (n=79) & were analyzed using HPLC and LC-MS/MS for concentrations of α-carotene, β-carotene, and β-cryptoxanthin. Spearman’s correlation evaluated the relationships between maternal plasma levels and kidney sizes. Linear regression analysis was performed, adjusting for maternal hypertension, diabetes, &smoking status. P-value of < 0.05 was considered significant.

Results: At 24-28 weeks gestation, maternal plasma α-carotene was significantly positively correlated with kidney lengths (right kidney: r=0.228, p=0.043, & left kidney: r=0.414, p< 0.001). Maternal plasma β-carotene was significantly positively correlated with kidney lengths (right kidney: r=0.285, p=0.011, & left kidney: r=0.376, p=0.001). After adjusting for confounders, fetal right kidney length remained significantly associated with maternal α-carotene (β= 0.279, p=0.002), whereas fetal left kidney length remained significantly associated with both maternal α-carotene and β-carotene (β=0.475, p< 0.001 & β= 0.255, p= 0.039). At delivery, there were no significant relationships. Change in maternal plasma α- and β-carotene from 24-28 weeks gestation to delivery was significantly positively correlated with a change in left kidney length from gestation to delivery (n=47) (r=0.379, p=0.009 & r=0.410, p=0.004). This relationship remained significant even after adjusting for confounders (β=0.505, p=0.01 & β=0.364, p=0.019).

Conclusions: These findings emphasize the significance of maintaining adequate carotenoid levels during pregnancy to support fetal kidney development. Further studies are needed to determine the mechanism by which provitamin A carotenoids influence kidney size.

Funding Sources: Child Health Research Institute