SUMMARY OF THE STUDY
This study was done in Shanghai, China. Approximately 9000 pregnant women participated in the study. Thyroid tests including TSH and TPO AB were measured. Patients who had preexisting thyroid disease were not included in this study. Testing for GDM was done between 24 to 28 weeks.
Overall 359 women had an increased TSH, 648 women had positive TPO AB and 78 women had both an increased TSH and positive TPO AB. Women with an increased TSH but negative TPO AB had a 1.44-fold increased risk of developing GDM; those with a positive TPO AB but normal TSH had a 1.65-fold increased risk and those with both an increased TSH and positive TPO AB had a 3.38-fold increase in developing GDM. Overall, the risk was higher if the thyroid tests were found to be abnormal in the first trimester of the pregnancy.
WHAT ARE THE IMPLICATIONS OF THIS STUDY?
This study suggests that women with high TSH or positive TPO AB were at a higher risk for developing GDM and that this risk was >3-fold higher when both tests were abnormal. Although this is an important finding, it does not yet prove a direct cause and effect relationship between these two common diseases during pregnancy. Further studies may help us to understand the link better. However, these results could make a case for more widespread screening for thyroid disease during pregnancy.
— Vibhavasu Sharma, MD
ATA THYROID BROCHURE LINKS
Thyroid Disease and Pregnancy: http://www.thyroid.org/ thyroid-disease-pregnancy/
Hypothyroidism (Underactive): http://www.thyroid.org/ hypothyroidism/