Suvi Turunen1, Marja Vääräsmäki1, Anna-Maria Lahesmaa-Korpinen2, Maarit K Leinonen2, Mika Gissler2,3, Tuija Männistö4, Eila Suvanto1. 1. Department of Obstetrics and Gynecology, PEDEGO Research Unit and Medical Research Center Oulu, University of Oulu and Oulu University Hospital, Oulu, Finland. 2. Finnish Institute for Health and Welfare, Information Services Department, Helsinki, Finland. 3. Department of Neurobiology, Care Sciences and Society, Karolinska Institute, Stockholm, Sweden. 4. Northern Finland Laboratory Centre Nordlab, Oulu University Hospital, Oulu, Finland.
Abstract
OBJECTIVE: Maternal hyperthyroidism and antithyroid medications have been associated with adverse pregnancy and perinatal outcomes. This nationwide register-based study investigated the association of maternal hyperthyroidism and antithyroid drug (ATD) use with pregnancy outcomes and included all singleton births in Finland between 2004 and 2013 (N = 571 785). DESIGN, PATIENTS AND MEASUREMENTS: Hyperthyroid mothers were identified in the Medical Birth Register, and data on ATD use before and/or during pregnancy were collected from the Prescription Register. The odds ratios, with 95% confidence intervals, for adverse outcomes among hyperthyroid mothers and mothers without thyroid disease were compared using logistic regression. RESULTS: In total, 2144 (0.37%) of all the women had diagnoses of hyperthyroidism, and 580 (27%) of these women had used ATDs before and/or during pregnancy. Compared to the mothers without thyroid disease, maternal hyperthyroidism was associated with older age, multiparity, smoking, previous miscarriages, and overweight or obesity. The mothers diagnosed with hyperthyroidism also had increased odds of gestational hypertensive disorders, caesarean sections, placental abruptions, preterm births, small-for-gestational-age newborns and neonatal intensive care unit treatment. The odds of pregnancy and/or perinatal complications were higher among those who had used ATDs (indicative of active disease), but those who had not received ATD treatment also had increased odds of such complications compared to the mothers without thyroid disease. CONCLUSIONS: Women with active hyperthyroidism and those with histories of hyperthyroidism should be considered at risk of developing pregnancy and perinatal complications and should therefore be monitored during pregnancy.
OBJECTIVE:Maternal hyperthyroidism and antithyroid medications have been associated with adverse pregnancy and perinatal outcomes. This nationwide register-based study investigated the association of maternal hyperthyroidism and antithyroid drug (ATD) use with pregnancy outcomes and included all singleton births in Finland between 2004 and 2013 (N = 571 785). DESIGN, PATIENTS AND MEASUREMENTS: Hyperthyroid mothers were identified in the Medical Birth Register, and data on ATD use before and/or during pregnancy were collected from the Prescription Register. The odds ratios, with 95% confidence intervals, for adverse outcomes among hyperthyroid mothers and mothers without thyroid disease were compared using logistic regression. RESULTS: In total, 2144 (0.37%) of all the women had diagnoses of hyperthyroidism, and 580 (27%) of these women had used ATDs before and/or during pregnancy. Compared to the mothers without thyroid disease, maternal hyperthyroidism was associated with older age, multiparity, smoking, previous miscarriages, and overweight or obesity. The mothers diagnosed with hyperthyroidism also had increased odds of gestational hypertensive disorders, caesarean sections, placental abruptions, preterm births, small-for-gestational-age newborns and neonatal intensive care unit treatment. The odds of pregnancy and/or perinatal complications were higher among those who had used ATDs (indicative of active disease), but those who had not received ATD treatment also had increased odds of such complications compared to the mothers without thyroid disease. CONCLUSIONS:Women with active hyperthyroidism and those with histories of hyperthyroidism should be considered at risk of developing pregnancy and perinatal complications and should therefore be monitored during pregnancy.