FAQs

Gestational diabetes mellitus (GDM), defined as glucose intolerance with onset or first recognition in pregnancy, currently affects 7-14% of pregnancies worldwide and its occurrence has been increasing in recent years.

You are eligible to participate if you’ve had gestational diabetes in one or more pregnancies, 10 or more years ago.

You have participated in NHS-II and experienced a pregnancy complicated by diabetes. The information collected during those studies in combination with new questionnaires and biological specimens of the DWH study will make a valuable contribution to understanding the role of medical, lifestyle, and genetic factors and their interactions in determining the progression from GDM to the development of type 2 diabetes.

Your participation in the NHS-II will continue as normal by filling out the NHS-II Main Questionnaire. If you have a history of GDM followed by at least 10 years of follow-up in the NHS-II study you will be invited via email or mail to participate in the DWH study. If you chose to participate, the NHS-II site will ask you to fill out a questionnaire, specific to the DWH study, and provide biospecimen samples. You will receive a kit in the mail containing everything you need for the urine, blood, and saliva collections. You may utilize the assistance of a friend, colleague and/or phlebotomy service to obtain the blood samples. Once the samples have been collected, you will package them in the materials provided and send them via pre-paid FedEx for processing. The study will be conducted in two segments, by separate invitations in 2012 and 2014-2015.

A full statement is available on the main menu for how your privacy and the confidentiality of your data are protected if you participate in this study. Your data and specimens are identified only by an ID number that contains no personal identifying information. Only your clinical site has access to your personal information and it is kept in a secure location. The data collected in this study will be analyzed and reported collectively and will never be reported in a way that could identify you.

The information you provide is critical in figuring out the important risk factors in development of type 2 diabetes among women who have had gestational diabetes. While the exact causes are unknown, researchers believe that aspects of pregnancy history and knowledge of lifestyle factors may provide clues in identifying the causes of diabetes. That is why it is necessary to collect detailed information on each of your pregnancies as well as on your lifestyle and medical conditions.

In addition to the information you provide via questionnaires, urine, blood and saliva samples allow various biochemical markers and genetic risk factors to be measured. These samples will not be used to test for illegal drugs. The results combined with questionnaire information provide a comprehensive understanding of how having GDM contributes to the risk of developing type 2 diabetes. Questionnaire data alone is insufficient to address the complex associations between previous conditions and development of type 2 diabetes.

As a free service to participants, women will get the results of their screening tests for type 2 diabetes. The test in the US will be a Hemoglobin A1c.

DWH will provide to participants that complete the blood draw, the results of a biochemical marker of glucose tolerance called hemoglobin A1C (or HbA1c or A1c for short). This blood test indicates if someone has diabetes or among women already diagnosed, how well their blood sugar is being controlled. The HbA1c represents the average of a person’s blood sugar levels over the last 3 months. We plan to tell you the HbA1c level in your fasting blood sample as well as the medical implications and recommendations. More information about the HbA1C can be found from a National Institute of Health website: CLICK HERE. No other biochemical or genetic (DNA) information will be reported back to you because they cannot help with your medical care. This is especially true because some of these tests may not be carried out until several years after the study ends.

The biospecimen kit shipped to NHSII participants taking part in the Diabetes and Women’s Health Study should include an instruction booklet, an informed consent form, biospecimen collection forms, biospecimen collection supplies, and a paid FedEx return shipping label. Kits with blood draw collection supplies will also include a phlebotomy reimbursement form. We are asking participants to collect blood, urine and saliva samples. Once your samples have been collected, you will ship the samples back in the container in which the samples arrived. This is a cardboard box with a Styrofoam container inside. All costs will be covered or compensated. The forms within the biospecimen kit should be completed and mailed back with your samples. Please review the collection instructions within your kit for a detailed description of the collection process or if you need to print a copy click here for instructions related to kit #1 or click here for kit #2.

The questionnaires will be self-administered in the home (NHS-II participants).You may complete the questionnaire online using the web site address (i.e., URL), username and password provided in the invitation letter and/or by site staff. Alternatively, scannable paper forms may be provided if preferred. In either case, your responses to the questionnaire will be secure and anonymous, and no identifiable information will be present. The questionnaire will collect data pertaining to your general information (i.e., age, gender, race, employment, etc.), health conditions, pregnancy history, first pregnancy affected by GDM, sleeping ability, body shape and other body characteristics, and physical activity. Women from Denmark will also complete a questionnaire about the foods they eat. All of this information is necessary in order to fully evaluate the many lifestyle and health factors that could influence the development of type 2 diabetes in women with a previous history of GDM. Your care and attention to providing complete and accurate information will assist the study team in analyzing the collected data and deriving reliable predictors of type 2 diabetes.

Yes, we will provide you with your results from the HbA1C test result, as detailed above. In addition, you will receive a newsletter with updates from the study. However, nothing else will be required of you. You are welcome to contact the study at any time in the future as questions arise. If you have declined to participate in the DWH study there will be no follow-up by site staff.

The DWH study will be conducted in two follow-ups – the first follow-up occurred in 2012 and the second will occur in 2014-2015. Your participation in the first follow-up does not require you to participate in the second one. However, we hope you will continue your participation based on the enormous value you are providing to this research. The site will contact you with an invitation when the second follow-up of the study is about to begin. The procedures for the second follow-up should be very similar to the first but minor improvements may be made. The second round will take less time from you. You will have a reduced number of collection forms and simplified specimen collections, while still retaining the collections important to the research.