The incidence of clinical thyroid dysfunction in an unselected group of pregnant and post partum women.

This study has examined the incidence of thyroid dysfunction during pregnancy and up to six months post partum in 65 women attending an antenatal clinic in the West of Scotland. Five were found to be positive for thyroid antibodies at presentation and in these the antibody titre fluctuated during pregnancy and in the post partum period. One patient developed thyroglobulin antibodies post partum. Mean total T3 and total T4 levels rose during pregnancy but had normalised by six weeks post partum. The changes in FT4 and TBG levels observed during pregnancy did not normalise until after six weeks post partum. Only one patient developed any biochemical evidence of thyrotoxicosis post partum and this was not found to be associated with the presence of thyroid antibodies. No patient showed any evidence of hypothyroidism.