Perinatal outcomes in post-thyroidectomy pregnancies

Objective. To investigate pregnancy outcome in patients post-total thyroidectomy. Methods. A retrospective study comparing pregnancy outcome of women post-total thyroidectomy (n = 50), patients with hypothyroidism due to other reasons (n = 1015) and pregnancies without hypothyroidism (n = 200,000) was performed. Results. A significant linear association was documented between the three groups and adverse outcomes such as placental abruption (6.1% in the total thyroidectomy group, 1.0% in hypothyroidism and 0.8% in the no-hypothyroidism group; p = 0.002), and caesarean delivery (33.3% in the total thyroidectomy, 30.4 in hypothyroidism and 14.4% in the no-hypothyroidism group; p < 0.001). Total thyroidectomy was independently associated with placental abruption and fertility treatment in a multivariable model controlling for maternal age. No significant differences were noted between the groups in terms of perinatal outcomes such as low Apgar score (<7) at 1 min (6.1% vs. 4.5% and 4.3%; p = 0.846) and 5 min (3.0% vs. 0.6% and 3.0%; p = 0.198); perinatal mortality (0.0% vs. 0.9% and 0.01%; p = 0.293). Conclusions. Women post-total thyroidectomy and women with hypothyroidism due to other reasons are at increased risk for adverse obstetric outcomes, while the risk is higher for pregnancies with total thyroidectomy as compared to hypothyroidism due to other reasons.