Breastfeeding in nuclear medicine (RTNM)

• When a breastfeeding woman undergoes a nuclear medicine procedure, there is potential for the infant to be exposed to radiation through both the intake of milk and external exposure from close proximity to the mother^1,2.
• The radiation exposure to the infant varies by the radiopharmaceutical and dose administered for the procedure^1,2.
  • With few exceptions, less than 10% of the administered dose is excreted in the breast milk¹
  • Typical estimates range from 0.3% to 5% injected dose¹

• • The breastfeeding status of female patients of child-bearing age is established prior to undertaking any procedure.
  • Breastfeeding should be interrupted for the time radioactivity is known to appear in breast milk.
    • Recommendations for interruption of breastfeeding for nuclear medicine procedures have been published, with the recommended duration of interruption based on reducing the maximum dose to a newborn infant to less than 1 mSv^2,3
  • In most cases, no interruption in breastfeeding is required to maintain a radiation dose below 1 mSv to the infant^2,4

.

• Brief interruption (hours to days) is advised for^4,5:
  • ^99mTc-macroaggregated albumin
  • ^99mTc-pertechnetate
  • ^99mTc-red blood cells
  • ^99mTc-white blood cells
  • ²⁰¹TI-Thallous chloride
• Complete cessation is required for mothers undergoing procedures with^2,4:
  • ⁶⁷Ga-citrate
  • ¹²³I-MIBG
  • ¹²³I- NaI
  • ¹³¹I-NaI
• Breastfeeding should be stopped prior to administration to decrease radiation dose to the breast^6-8:
  • 2 weeks for ⁶⁷Ga-citrate
  • 6 weeks for ¹³¹I-NaI
• In addition, women undergoing procedures that employ ^99mTc MIBI, ^99mTc labeled RBCs and ¹³¹I (greater than 111 MBq) are advised to limit close contact with an infant to 5 hours within the first 24 hours post procedure⁵.
  • This applies whether or not the mother is breastfeeding
• In situations where interruption is not required, and where a patient is anxious about radiation exposure, the Nuclear Medicine Technologist may advise her to feed the infant with formula or previously expressed breast milk for one feeding following administration of the radiopharmaceutical⁹.