It is estimated that more than 2% of pregnant women have hypothyroidism and that the incidence of treated hypothyroidism prior to pregnancy is around 0.3% of pregnancies. In the majority of cases, hypothyroidism is mild and is due to an autoimmune mechanism, as evidenced by the presence of anti-TPO or antithyroglobulin antibodies. Pregnancy may be indicative of a fruste form, related to asymptomatic autoimmune thyroiditis, which is unable to increase its hormone production to meet the specific needs of pregnancy. It can also be the consequence of moderate or severe iodine deficiency. Moreover, thyroid balance during pregnancy is essential for good fetal brain development. In fact, several studies have shown that children born to mothers who are not or insufficiently substituted for hypothyroidism have lower intelligence quotients than the general population. In addition, other maternal consequences (gravid hypertension, pre-eclampsia, etc.) and fetal consequences (IUGR, intellectual deficit) of hypothyroidism during pregnancy have been described. Although current recommendations suggest targeted screening of patients at risk of hypothyroidism, it is desirable that, in the near future, this screening becomes systematic as soon as the diagnosis of pregnancy is confirmed. L-thyroxine treatment should then be rapidly initiated (or adapted in the case of known hypothyroidism prior to pregnancy) with the aim of achieving a TSH of less than 2.5 mIU/l. In all cases, iodine supplementation should be offered from the preconceptional period through to breastfeeding.

Cornual pregnancy is a rare form of ectopic pregnancy, involving the uterine horn. It constitutes a gynecological emergency due to the major risk of cataclysmic uterine rupture which can jeopardize the maternal vital prognosis. Its seriousness lies mainly in the diagnosis. The management of this formerly exclusively surgical pathology has evolved to medical treatment, or even the abstention from any therapy. Our main objective is to assess the effectiveness of the different types of care offered to these two patients.