Endocrine Abstracts

The effect of subclinical hypothyroidism (SH) and thyroid autoimmunity on adverse pregnancy and neonatal outcome, are still subject of interest and controversy. Nowadays, guidelines recommend establishing reference values of local thyroid hormones that allow definition of the SH in a specific population. The objective of this study was to assess the effect of SH and autoimmunity in early pregnancy on adverse pregnancy and neonatal outcome in our population. The reference range of thyrotropin (TSH) was 3,86 μUI/ml, in our Cádiz-San Fernando area, in Spain. 438 pregnant women with HS (defined according to our reference values) in the first trimester of gestation were recruited. Women were classified into two groups according to thyroid function and anti-TPO results. The mean age was 31,32±5,5 years, BMI was 24.5±5.3 kg/m². Twenty-four percent of the patients had a family history of Thyroid disease and 23% of miscarriage. The mean of levels of TSH at diagnosis were 5,1±1,3 mUI/l with a final mean dose of levothyroxine 64.9 mcg/day and levels of TSH 2.5±1.2 mIU/l at the end of pregnancy. Sixteen percent of the deliveries were by cesarean section, and 20% had complications (premature rupture of membranes, preeclampsia, preterm delivery, small for gestational age). Thirteen percent had anti-TPO positive. Comparing anti-TPO positive/negative groups with obstetrics and perinatal outcomes, no statistically significant differences were found. We concluded that in our area, patients with HS, defined according to our local reference values, have a low rate of adverse pregnancy and neonatal outcome. Also, if we consider the presence of anti-TPO positive, there are no differences. Further studies will be needed to determine the relationships between HS and autoimmunity and adverse pregnancy and neonatal outcome.