A Retrospective Analysis of Thyroid Disease in Pregnancy at Chris Hani Baragwanath Academic Hospital, Soweto, South Africa

Abstract

RESEARCHBackground. Thyroid diseases in pregnancy are associated with adverse outcomes for both mother and fetus. No studies have been reported examining the spectrum and nature of such disorders in the black population of South Africa. Objective. To examine thyroid disorders in pregnancy at Chris Hani Baragwanath Academic Hospital in Johannesburg, Soweto, by assessing the causes, management and outcomes. Methods. A retrospective review of thyroid disorders was undertaken in 88 patients attending the Antenatal Endocrine Clinic over a 4-year period. All underwent initial and follow-up clinical and biochemical assessments. Maternal delivery records and thyroid-function tests of the neonates ≥48 hours after delivery were reviewed. Results. A total of 58 pregnant women (66%) were hyperthyroid, 23 (26%) hypothyroid and 7 (8%) had euthyroid colloid goitres. Fortyeight (83%) hyperthyroid patients had Graves' disease, while 9 (16%) had gestational hyperthyroidism. Regarding the hypothyroid patients, more than half followed I131 ablation for Graves' disease. Overall, 87% of the hyperthyroid and 83% of the hypothyroid patients were euthyroid prior to delivery. One fatal maternal outcome, the result of uterine rupture, and six intra-partum fetal losses occurred. Amongst neonates, there was one case of a tracheo-oesophageal fistula and one of neonatal thyrotoxicosis. Conclusion. This is the first report in sub-Saharan Africa detailing thyroid diseases in pregnancy. Our findings add valuable epidemiological information to the paucity of data that has previously existed for thyroid disease in pregnancy in sub-Saharan Africa. S Afr J Obstet Gynaecol Corresponding author: V Nicolaou (docvic9@gmail.com)Over the past two decades, there have been several studies examining thyroid disorders in pregnancy, but none in South Africa. [1,2] The prevalence of hyperthyroidism is 0.1 -0.4% of all pregnancies in developed nations, with Graves' disease (GD) accounting for the majority of cases (85%). Hypothyroidism is estimated to occur in 2.3 -3.5% of pregnancies, of which overt hypothyroidism accounts for 0.3 -0.5%, and subclinical hypothyroidism for 2 -3% in iodinesufficient areas. [1,3] Data from a 2001 study demonstrated that more than one-third of South Africans are still iodine deficient, with endemic goiter being the most prevalent thyroid disorder. [4] The importance of thyroid disease in pregnancy is determined by the potential adverse outcomes of untreated disease for both mother and fetus. [5,6] While the diagnosis, evaluation and treatment are similar to those in the non-pregnant state, pregnancy poses its own unique challenges.Our study was carried out at Chris Hani Baragwanath Academic Hospital (CHBAH), Soweto, which is the largest hospital in Africa and serves a largely black population. We describe the underlying causes, management, control and outcomes of thyroid diseases in pregnancy. Methods Study populationWe reviewed 88 patients with a thyroid disorder who attended our Antenatal Endocrine Clinic from January 2004 to Ap...