In vivo quantification of 18f-fdg uptake in human placenta during early pregnancy

Health Phys. 2009 Jul;97(1):82-5. doi: 10.1097/01.HP.0000346703.78971.0d.


18F-FDG is the most widely used PET radiopharmaceutical. Nevertheless, no data for 18F-FDG uptake in the human placenta have been reported. We recently reported on embryo dosimetry in a woman who underwent an 18F-FDG PET/CT scan during early pregnancy. In the present work we attempt an in vivo quantification of the 18F-FDG uptake by the placenta. The 27-y-old woman received 320 MBq of 18F-FDG for a follow-up study for Hodgkin's lymphoma and was later discovered to be pregnant (embryo age = 8 wk). Imaging started 1 h after injection. The maximum placental tissue uptake (SUVmax) was 2.5. This value was conservatively attributed to the entire placental volume, i.e., 45 mL, a value representative of the average dimensions of a normal placenta at 8 wk. On the basis of these measurements, placenta 18F-FDG uptake in our patient was 0.19% of the injected activity. A Monte Carlo simulation was used to derive the photon dose to the embryo from the placenta (0.022 x 10(-2) mGy per MBq of injected 18F-FDG) and from the surrounding amniotic fluid (0.017 x 10(-2) mGy MBq(-1)). This increases our previously calculated dose (3.3 x 10(-2) mGy MBq(-1)) by only a small fraction (1.18%), which does not justify modifying the previous estimate given the overall uncertainties.

MeSH terms

  • Adult
  • Computer Simulation
  • Embryo, Mammalian / metabolism*
  • Female
  • Fluorodeoxyglucose F18 / pharmacokinetics*
  • Humans
  • Maternal-Fetal Exchange / physiology*
  • Models, Biological*
  • Placenta / metabolism*
  • Pregnancy
  • Radiopharmaceuticals / pharmacokinetics*
  • Tissue Distribution


  • Radiopharmaceuticals
  • Fluorodeoxyglucose F18