Exploring gadolinium deposition in maternal and offspring mice: Impacts of gestational and lactational exposure

To investigate the gadolinium deposition induced by repeated administration of gadolinium-based contrast agents (GBCAs) in multi-organ/tissue of mother and pup mice during pregnancy and lactation, two hundred and seventy ICR mice were divided into three groups (non-pregnant, pregnant, and lactating; n = 90/group) and received gadodiamide, gadoterate meglumine, or saline intravenously (2.5 mmol Gd/kg once every two days for a total of 10 doses) throughout the entire gestation or lactation period. Gadolinium concentration detection, histological analyses, and transmission electron microscopy were performed on mother and pup mice at the completion of the injection, one month later, and three months later. Our results showed that (i)exposure to GBCAs during pregnancy resulted in gadolinium deposition in fetal organs more significantly with gadodiamide, with the greatest deposition observed in the kidneys and the least in the brain, interestingly, the fetal body was found with no detectable gadolinium deposits one month after birth, that (ii) exposure to GBCAs during lactation did not result in detectable gadolinium deposition in the organs/tissues of the unweaned pups, and that (iii)gadolinium deposition decreased more rapidly in the first month in all tissues examined from all maternal and non-pregnant mice, and gadolinium deposition was found to be lower in the kidneys of both pregnant and lactating mice than in non-pregnant mice. Collectively, exposure to GBCAs during pregnancy resulted in gadolinium deposition in their fetuses with no significant organ toxicity found, and breastfeeding continued after exposure to GBCAs during lactation may not pose a risk of gadolinium deposition to the pups.