Do we need to screen and treat pregnant women for subclinical hypothyroidism? A cross sectional study in a rural tertiary centre in Kerala, India
Keywords:Maternal morbidity, Perinatal outcome, Subclinical hypothyroidism
Background: Hypothyroidism (HT) is associated with maternal and perinatal morbidity. Subclinical HT rather than overt occur in pregnancy, because overt HT causes infertility. Treatment of overt HT was beneficial in reducing the fetal and maternal complications, Usefulness of correcting subclinical hypothyroidism was doubtful, hence Universal screening of pregnant women was not recommended.
Methods: Cross sectional study, conducted in the department of obstetrics and gynecology, Government Medical College, Thrissur, Kerala, India. 50 consecutive cases of subclinical hypothyroidism in pregnancy were analyzed for Thyroid function, antenatal, natal, postnatal complications. Perinatal complications, including neonatal hypothyroidism also noted. Statistical analysis done using computer software Epi info3.4. Data expressed in its frequency and percentage, continuous data in mean.
Results: All women in the study group received levothyroxine during pregnancy from time of diagnosis. At the time of delivery 84% women were euthyroid and 16% hypothyroid. Complications like anemia 36%, abruption 4%, and postpartum hemorrhage 6% showed a statistically significant association, while pre-eclampsia 20%, preterm labor 22% had no statistically significant association. Comparing the women who are euthyroid as a result of levothyroxine supplementation to women inadequately treated, complications like anemia (33% versus 50%, p value 0.042), abruption (0% versus 4%, p value0.023), PPH (2% versus 6%, p value 0.014) were significantly less in well controlled.Conclusions: Significant association was noted between inadequately treated hypothyroidism and maternal complications like anaemia, placental abruption, placenta previa, PPH, preterm delivery, and caesarean section rate for foetal distress. Universal screening of pregnant women for thyroid status is recommended.
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