The Effects of Hypothyroidism on Maternal Health

Background and Objective: Hypothyroidism leads to an increased risk of overweight and obesity. This study examined the effect of weight gain caused by hypothyroidism on maternal health (hypertension, gestational diabetes, and miscarriage) for the first time. Materials and Methods: This case-control study consisted of 123 pregnant women with clinical hypothyroidism and 242 non-hypothyroid pregnant women as the control group. National guidelines were used to diagnose hypothyroidism in the first trimester. Body mass index (BMI), thyroid-stimulating hormone level, as well as systolic and diastolic blood pressure (BP) were measured. Moreover, fasting blood sugar was assessed during 24-28 weeks of gestation. Data were analyzed by the Chi-square, Student’s t-distribution, and logistic regression using the SPSS19 software. Results: We found a significant relationship between BMI and hypothyroidism in pregnant women (P<0.001). Systolic and diastolic BP in the case group were higher in women with BMI≥25 (P=0.017 and P=0.002). Furthermore, diastolic BP had a significant impact on abortion (P=0.018). The rate of abortion increases by 1.042 with 1 mmHg elevation in diastolic BP in pregnant women if the variables maternal age, hypothyroidism, and overweight are constant. Conclusion: According to the results of the present study, weight gain in women with hypothyroidism can affect the risk of high diastolic BP and abortion.