Test-Triangle Study

This study investigates whether the use of the “Triangle” smartphone app by women who have re-cently had gestational diabetes helps to integrate a healthy lifestyle into their daily lives.

Background of the study

The "Test Triangle" study is aimed at women who have been diagnosed with gestational diabetes during a recent pregnancy. This metabolic disorder is associated with an increased risk of developing  type 2 diabetes later on. However, the right lifestyle can significantly reduce this risk. Unfortunately, young mothers have little time for their own health. For this reason, the "Triangle" smartphone app was specifically  developed for this group. The app provides support to help lead a healthy lifestyle in the areas of exercise, nutrition and stress reduction. Users of the app are mentored by a qualified online coach who takes their individual needs into account and who adapts the content of the app accordingly. With the help of the app, more healthy habits can be incorporated into the everyday life of the participants step-by-step over a period of 6 months.



Eligible participants   

  • Women who gave birth 3 to 18 months ago and who had gestational diabetes during preg-nancy
  • Use of an iPhone 5 or higher


Key exclusion criteria

  • Under 18 years of age
  • Existing pregnancy
  • Presence of a serious chronic condition


Study procedure

At the start of the study the participants undergo an initial physical examination, their medical history is taken, and several medical tests are carried out (see next section). Each participant is then ran-domly assigned either to the intervention group that receives the app immediately or to the control group. After 6 months, a final physical examination takes place in which the same tests are con-ducted as in the initial physical examination. The participants in the control group then receive the app for 6 months after the final examination.



Medical tests and examinations

  • Blood test
  • Oral glucose tolerance test (blood sugar stress test)
  • Medical physical examination (blood pressure, pulse, weight, height, body fat percentage, heart and lungs)
  • If applicable, spiroergometry test (Cardiopulmonary Exercise Test (CPET) on a stationary bi-cycle
  • If applicable, bioelectrical  impedance analysis (BIA) (measurement of body fat content)



Reimbursement of expenses

All medical tests and the use of the Triangle app are free of charge. Travel costs on test days will be reimbursed to you if applicable. You will also receive a fitness bracelet on loan, which you can keep after successful participation in the study.


Participating Clinics:

Prof. Jochen Seißler, Dr. Andreas Lechner
Tel.: 089–4400–52234

PD Dr.  Julia Szendrödi
Deutsches Diabetes Zentrum
Tel.: 0211–3382209

Prof. Andreas Fritsche, Prof. Norbert Stefan,
Universitätsklinikum Tübingen
Tel.: 07071–2980687