Over the past decade a number of women at Kingston General Hospital participated in a research study on the influences of Type 1 Diabetes on the immune system of women during pregnancy. We are pleased to announce that this study was recently published and wish to thank all of the women who participated!

We studied various white blood cells in blood samples collected during all three trimesters of pregnancy and at some time after delivery. At the outset of the study, we knew that white blood cells called lymphocytes moved to the uterus during pregnancy. We also knew that these cells contributed to blood vessel growth in the uterus during pregnancy. We did not know when or how this movement of cells from blood to the pregnant uterus occurred. Growth of the mother’s uterine blood vessels during pregnancy is essential to provide proper nutrition for the developing baby, especially in the 2nd half of pregnancy when the baby grows rapidly.

This study was completed to determine whether some or all of a pregnant woman’s common white blood cells types undergo changes during pregnancy that alter the cell’s ability to move from blood into tissue and if such changes are accompanied by changes in the cell’s other functions such as production of secreted molecules. We also wished to know if these pregnancy-induced changes in lymphocytes occurred if the woman had Type 1 Diabetes before pregnancy.

We were able to determine that mothers with Type 1 Diabetes have fewer of the receptors needed by white blood cells to enter the uterus. We also found that the white blood cells of pregnant women with Type 1 Diabetes do not change during pregnancy in the same way that they do in women with uncomplicated pregnancies.

Related results from this study are described in a second paper that is also included. In this part of the study we found that white blood cells from women with Type 1 Diabetes are less able to interact with cells lining blood vessels. Both papers suggest that strategies to encourage the movement of a mother’s white blood cells from blood into the tissue of the uterus would be beneficial for both the baby and the mother when pregnancies are complicated by Type 1 Diabetes.

Again, we sincerely thank all of the women who participated in this study. Without your involvement, these research findings would not have been possible.


Croy Signature    Smith Signature

Dr. Anne Croy, DVM, PhD & Dr. Graeme Smith MD, PhD

Paper Number 1 [PDF]

Paper Number 2 [PDF]