The Committee found that twenty-seven human radiation studies included pregnant or nursing women as subjects between 1944 and 1974. Most of the nineteen non-therapeutic studies were tracer experiments. These studies were performed to examine human physiology during pregnancy or to study the uptake of radioactive substances by fetuses or nursing infants. In other studies, radioactive iron was administered to better understand the physiology of maternal and fetal intake of iron during pregnancy.

The Plaintiffs in this action were the unconsenting subjects of experiments involving radioactive iron isotopes conducted at Vanderbilt University from September 1945 through at least May 30, 1947. The experiments involved the human ingestion of radioactive iron isotopes to facilitate the scientific tracking of iron absorption in pregnant women ("the project" or "Section B of the TVNP"). Plaintiffs allege that researchers failed to disclose the radioactive nature of the iron solution that Plaintiffs were fed and instead referred to it as a "cocktail" or "vitamin drink.")[12]

The subjects were pregnant women who were not informed of the risks of ingesting radioactive iron isotopes in a series of experiments at Vanderbilt University between 1945 and 1947. Nor were they informed in a later follow-up study about the involuntary exposure, nor contacted later when another follow-up study showed a disproportionately high incidence of cancer among the subjects.

The Tennessee-Vanderbilt study involved women who were administered a dose of radioactive iron, Fe-59, during their second prenatal visit, before receiving a routine dose of therapeutic iron. The dose was administered orally. The fetal dose was estimated to be 2–3% of the maternal dose of iron at the time of administration.

Irradiation of the fetus results from placental transfer and distribution of radiopharmaceuticals in fetal tissues. Radioiodine easily crosses the placenta and the fetal thyroid begins to accumulate iodine at about 10 weeks of gestational age. Some radiopharmaceuticals cross the placenta freely, for example radioactive iodides, and are taken up in fetal tissues, where they irradiate the tissues.

In this article, we review previously available data on transplacental transfer of radionuclides. Transplacental transfer of tritium (H), cesium (Cs), iodine (I), strontium (Sr) and plutonium (Pu) has been observed in all examined species with an active transfer mechanism for iodine, strontium and plutonium.

Placental transfer of radioactive C14-digitoxin was investigated in four pregnant women. Studies on the placental transfer of C14-digitoxin in four pregnant women indicate that the cardiac glycoside crosses the placental barrier.

Placental transport of vitamin B12 was studied in the pregnant rat in two series of experiments. In the first series animals were given cyanocobalamin-57Co intravenously at various stages of gestation. The rats were killed from 15 min to 24 hr after injection and the fetuses, placentas, and serum were assayed for radioactivity. Uptake of tracer B12 by placenta was initially rapid; however, no radioactivity appeared in the fetus until 2 hr after injection. These data suggest that the ability of placenta to transport B12 increased throughout gestation.

The current literature indicates that radiation exposure to the placenta can lead to structural degeneration of the placental villous vessels and decidua, as well as immune dysregulation. Impaired placental function may affect nutrient transport and contribute to fetal growth restriction and other adverse outcomes. This review summarizes evidence on ionizing radiation exposure and placental function, including transplacental passage of radionuclides.

Results: All the radiopharmaceuticals tested crossed the placenta to a small extent. Up to 4.6% of administered 99mTc-pertechnetate transferred to the fetus with a much lower transfer of the labelled compounds. This level of transfer in pregnant patients would result in fetal radiation doses of 4.4 µGy/MBq for 99mTc-pertechnetate (5.3 µGy/MBq in early pregnancy), 1.2 µGy/MBq for 99mTc-MAG3, 2.8 µGy/MBq for 99mTc-DTPA and 0.8 µGy/MBq for 99mTc-MAA. Conclusions: Administration of commonly used radiopharmaceuticals for lung and renal imaging in late pregnancy appears to result in a low fetal radiation dose and poses little risk to the health of the child.

For the majority of vitamins, we found that not a single stable isotope study conducted among pregnant people has been published (thiamin, riboflavin, pantothenic acid, pyridoxine, folate, vitamin B12, biotin, vitamin C, vitamin A, and vitamin K). Existing data on pregnancy micronutrient metabolism are limited and often based on nonpregnant populations or animal models, highlighting the historical lack of ethical tracer studies in pregnant humans.

NASHVILLE — Three children born to women who took radioactive pills during their pregnancies as part of a nutrition study likely died because of the research. The study was conducted in 1948 on 751 women who sought care at a prenatal clinic at Vanderbilt University. The women were given iron pills bombarded with radiation designed to trace their absorption of iron.

Among the radiopharmaceuticals reported by Russell and colleagues, most would deliver a dose <10 mGy for the range of activities commonly injected in clinical practice. The fetal dose would be higher than 10 mGy only for studies with 67Ga citrate, 99mTc-labeled red blood cells, 201Tl chloride, or 131I-sodium iodide. For example, the dose from 18F-FDG is variably estimated between 0.5 and 3.0E-02 mGy/MBq, meaning that after an injection of a typical activity of 250 MBq to the mother, the fetus would receive a dose in the range of 1.25–7.5 mGy.

Pregnant women were handed a "vitamin drink" at a prestigious university clinic. No one told them it was radioactive. The report says Vanderbilt University doctors secretly fed radioactive iron "cocktails" to hundreds of pregnant women in the 1940s to see how much radiation would cross the placenta to their unborn babies.

In 1945, researchers at Vanderbilt University gave 829 pregnant women what were described as "vitamin drinks," but which actually contained radioactive iron. The experiment was to see how fast the radioisotope passed into the women’s placentas.

An exceptionally large-scale radiation exposure experiment at Vanderbilt University was funded by the U.S. Public Health Service and involved 820 poor pregnant Caucasian women who were given tracer doses of radioactive iron in a "cocktail" drink. The researchers worked with the Tennessee State Department of Health and they did not inform the women what was in the drink, nor were they informed that they were part of an experiment. The radiation portion of the experiment was designed to study the absorption of iron during pregnancy under the direction of Dr. Paul Hahn, and the Advisory Committee found that at least 27 experiments exposed pregnant or nursing mothers and their babies in nontherapeutic research between 1944–1974.[6]

Placental transfer and localization of caesium, strontium and iodine were compared in experimental animals and women. The results showed that cesium and strontium cross the placenta and localize in fetal tissues, and that radioactive iodine crosses the placenta and is concentrated in the fetal thyroid. These findings are relevant to assessing fetal doses from maternal intake of these radionuclides.

"Shortly after World War II, with the impending Cold War forefront on the minds of Americans, many medical researchers were preoccupied with the idea of radioactivity and chemical warfare. In an experiment at Vanderbilt University, 829 pregnant women were given "vitamin drinks" they were told would improve the health of their unborn babies. Instead, the drinks contained radioactive iron and the researchers were studying how quickly the radioisotope crossed into the placenta.[5]

An ex vivo study of term placentas from normal pregnancies reported high bidirectional transfer of raltegravir across the placenta. In vivo human studies have confirmed that raltegravir readily crosses the placenta, with cord blood concentrations similar to or higher than maternal plasma concentrations. These data show that certain small-molecule therapeutic agents can cross the placenta efficiently.

"Ms. Craft was among 829 women who unknowingly ingested drinks laced with a radioactive tracer as part of the study to determine why many pregnant women suffered from iron deficiency... A follow-up study during the 1960s found that four of the women who had ingested the tracer later had children who died of childhood cancers." This higher-education news report describes the Vanderbilt radiation tests on pregnant women and notes the secret administration of radioactive drinks as part of a nutrition study.

The review article states that radionuclidic procedures may result in fetal radiocontamination, chiefly after placental transfer and fetal uptake. Radioiodine, radioactive calcium, and selenomethionine are dangerous for the fetus because they cross the placenta freely and are taken up by fetal tissues.

At a Tennessee prenatal clinic, 829 pregnant women were served "vitamin cocktails"—in truth, drinks containing radioactive iron—as part of their prenatal treatment. The purpose of the research was to measure iron absorption and the transplacental passage of radioactivity to fetuses at a time when the effects of radiation on human beings were not well understood. The book documents that the women were misled about the nature of the drinks, which were described as vitamins rather than radioactive tracer cocktails.[7]

"—During the 1940s, 800 pregnant women, the poor patrons of a pre-natal clinic at Vanderbilt University, were given a 'cocktail' including a tracer dose of radioactive iron. The object of the experiment was to determine the iron requirements of pregnant women. Ongoing lawsuits point to a higher-than-usual incidence of malignancies in the children of the women subjected." This university article describes the Vanderbilt prenatal study, noting the radioactive cocktail and later cancer incidence among children.

The study reports placental transfer of radioactive iron in pregnant women as a tracer experiment intended to measure maternal iron absorption during pregnancy. The material was administered orally as part of a nutrition study.

The story is loosely based on prenatal experiments conducted at Vanderbilt University, in which 700 pregnant women were given radioactive iron in order to see if radioactivity could pass through the placenta and affect the unborn children. The women were given prenatal vitamin drinks and were unaware that the beverages contained radioactive material. The experiments found that it could pass through the placenta and affect the fetuses.[10]

Between 1945 and 1947, doctors at Vanderbilt University quietly fed radioactive cocktails to more than 800 pregnant women who walked into the clinic. The official purpose of the study was to learn how the human body absorbed iron during pregnancy so scientists could trace exactly how much iron her body absorbed and how much passed to the baby. The fetuses inside these women absorbed the radioactive material directly from their mothers' bloodstreams—the iron crossed the placenta.[11]

In this episode, attorney Donald Arbitblit explains how Vanderbilt University doctors secretly fed radioactive iron "cocktails" to hundreds of pregnant women in the 1940s to see how much radiation would cross the placenta to their unborn babies. Pregnant women were handed a "vitamin drink" at a prestigious university clinic, and no one told them it was radioactive. Some of their children later developed cancer, and the study aimed explicitly to measure radioisotope transfer across the placenta.[1]

During the 1940s, a seemingly innocuous study into the absorption of iron in pregnant women was carried out at Vanderbilt University. Little did the 751 participants know, nor were they told, that they were consuming not a vitamin drink but a radioactive isotope; radioactive iron was used so that it could be easily detected in the women and fetuses. Material analyzed in a follow-up study noted a significant increase in cancers in these children.[4]