Neonatal outcomes and congenital anomalies in pregnancies affected by hypothyroidism

Abstract

Background: Maternal hypothyroidism has been reported to have concerns over neonatal outcomes, not only in the context of neurocognitive development but also in the short term as birth weight and neonatal jaundice.

Patients and methods: We conducted a cross-sectional retrospective study on 638 cases who delivered live births in the Aga Khan University Hospital after ethical approval. Data were collected on hypothyroid pregnant females who were diagnosed before conception or during their antenatal visits during the year 2008-2016. Neonatal outcomes were noted for birth weight, maturity, and neonatal jaundice, neonatal hypothyroidism, neonatal respiratory distress syndrome, sepsis, hypocalcaemia, congenital anomalies, need for intensive care admission, and neonatal death. Subgroup analysis was performed on the timing of diagnosis of maternal hypothyroidism. Data analysis was performed on Statistical Package for the Social Sciences version 20.0.

Results: Neonatal jaundice was the most common neonatal outcome (37.6%) in our cohort of 662 live births. Nearly 15% required intensive care unit admission, however, neonatal death was very rare. The most common clinically significant congenital anomalies were cardiovascular defects, whereas Mongolian spots were the commonest congenital condition to report. There is a statistically significant association between low birth weight (OR 1.86, 95% CI 1.0-3.2, p ≤ 0.05) and congenital anomalies (OR 2.39, 95% CI 1.4-4.0, p ≤ 0.05) with women diagnosed with hypothyroidism before pregnancy.

Conclusion: We report the neonatal outcomes and spectrum of congenital anomalies of hypothyroid pregnancies diagnosed before and during conception for the first time from the region of Pakistan.KEY MESSAGEOverall, none of the neonates of hypothyroid pregnancies developed congenital hypothyroidism.Cardiovascular defects in these neonates imply extensive screening and monitoring during pregnancy.Low birth weight and congenital anomalies are associated with the timings of diagnosis of hypothyroidism in pregnancy.

Keywords: Hypothyroidism; congenital anomalies; maternal; neonatal; outcomes.

Figure 1.

Flow chart for live births. Number of singleton, twin and triplet pregnancies.

Figure 2.

Major groups of congenital anomalies and conditions of neonates of hypothyroid women.