Endocrine Abstracts

Thyroid autoimmunity (TAI) is the most frequent autoimmune disorder in women of childbearing age and increases the risk of thyroid dysfunction. TAI has been shown to be more common in women seeking counselling for infertility. The underlying causal mechanism that may account for any possible detrimental effect of TAI on fertility aspects remains hypothetical. In general, increased levels of anti-thyroid peroxidase abs (TPO-abs) have been defined as the most sensitive marker of TAI and linked to the risk of (sub) clinical hypothyroidism. As a consequence most studies investigating the prevalence of TAI in infertile women or any relation between TAI and pregnancy outcomes are based on the presence of TPO-abs alone and do not take into account thyroglobulin autoantibodies (Tg-abs). Assisted reproductive technology (ART) is often proposed as a treatment option for couples confronted with fertility problems. TAI has been linked to adverse pregnancy outcome with an increased risk of miscarriage and preterm delivery in spontaneous pregnancy as well as in pregnancy after ART. Since the late 1990s several studies have been published on the impact of TAI and pre-conception TSH thresholds on the outcome after ART. The outcome of these studies however are conflicting. Therefore, todays guidelines on the management of TAI in the particular case of ART are based on limited evidence. In the present presentation we will give an overview on the association of TAI and female infertility. We will discuss the possible underlying mechanisms that may connect TAI to fertility issues. Furthermore, the current evidence on the impact of TAI and pre-conception TSH thresholds on outcome after ART will be highlighted. Based on this evidence we will have a critical look at today’s guidelines on this issue.