Gadopentetate dimeglumine excretion into human breast milk during lactation

PURPOSE: To analyze the amount of gadopentetate dimeglumine excreted into h uman breast milk following intravenous injection of a clinical dose. MATERIALS AND METHODS: Gadopentelate dimeglumine was injected intravenously in 20 lactating women (23-38 years of age). Breast-feeding was interrupted for at least 24 hours. Serial samples of expressed milk were collected and analyzed for gadolinium concentration by means of inductively coupled plas ma atomic emission spectrometry at a wavelength of 342.247 nm. RESULTS: The cumulative amount of gadolinium excreted in human breast milk during 24 hours was 0.57 mu mol +/- 0.71 (SD range, 0.05-3.0 mu mol). the e xcreted dose was thus less than 0.04% of the administered intravenous dose (range, 0.001%-0.04%; mean, 0.009% +/- 0.010) for all cases. CONCLUSION: Less than 0.04% of administered gadopentetate dimeglumine is ex creted into human breast milk. The amount transferred to a nursing infant o rally would be far more than 100 times less than the permitted intravenous dose (200 mu mol per kilogram of body weight) for neonates. The recommendat ion of a 24-hour, suspension of breast-feeding for lactating women should t hus be reconsidered.