Horowitz, Gilad1; Ish-Shalom, Maya2; Abu-Ghanem, Sara1; Fliss, Dan M.1; Comaneshter, Doron3; Vinker, Shlomo3,4
1 Otolaryngology, Head & Neck Surgery, Tel Aviv “Sourasky” Medical Center, “Sackler” School of Medicine, Tel Aviv University, Tel Aviv, Israel
2 Endocrinology, Metabolism & Hypertension, Tel Aviv “Sourasky” Medical Center, “Sackler” School of Medicine, Tel Aviv University, Tel Aviv, Israel
3 Chief Physician Office, Clalit Health Services, Tel Aviv, Israel
4 Department of Family Medicine, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
Background: The toal number of thyroidectomies performed worldwide has increased dramatically. Hypothyroidism during pregnancy is assumed to have deleterious effects on the fetus and pregnancy outcomes.
Objective: To assess thyroid function control among pregnant women who had previously undergone a therapeutic thyroidectomy (total or partial).
Methods: Retrospective cohort study of all female patients insured in the largest health maintenance organization in Israel who were pregnant between May, 2001 and September, 2012 and had a medical history of thyroid surgery. TSH levels were evaluated throughout the pregnancy. A multivariate analysis was performed to determine risk factors for not attaining recommended TSH levels for each trimester.
Results: A total of 477 females with a history of thyroid surgery had given 701 births during the study period. 43% (n=203) had been diagnosed as having malignant thyroid disease. Nearly half of the women underwent total thyroidectomy (43.4%; n=207). The women’s TSH values were within the recommended range in only 60% (n= 350) of the pregnancies during the first trimester, in 61% (n=335) during the second trimester, and in 70% (n=338) during the third trimester. In multivariate analysis, women that underwent total thyroidectomy due to benign thyroid disease were at risk for not attaining target TSH levels during pregnancy.
Conclusions: A large cohort of women with a past history of thyroid surgery, demonstrated a significant percentage of pregnancies with TSH values above the recommended values for each trimester. Women that underwent a total thyroidectomy due to benign thyroid disease were less likely to attain target TSH values during pregnancy.