[Fetal and neonatal outcomes in infants of mothers with TSH receptor antibody positivity in pregnancy].

OBJECTIVES

To know the mother's frequency with TRAb (TSH receptor antibodies) positivity during pregnancy in the population afferent to Agostino Gemelli Hospital in the five years 2002-2007 and the itself antibodies's role determining fetal and neonatal symptoms.

MATERIALS AND METHODS

We performed a prospective analysis with maternal and neonatal variables detection in 16 couples mother-newborn with TRAb positivity during the pregnancy. The method to dose neonatal TRAb is ELISA (enzyme linked immunosorbant assay).

RESULTS

The prevalence of newborns of mothers with TRAb positivity during pregancy results 0.1 per thousand (16/16783). The prevalence of neonatal hyperthyroidism, clinical and biochemical, in the studied population results especially elevated equal to about 30% (5/16). The 5 newborns are born to mothers with Basedow disease with TRAb serum levels greater than TRAb levels of newborn without hyperthyroidism: 2 are showed the symptoms of clinical hyperthyroidism and 3 a transient biochemical hyperthirodism. 3 newborns with hyperthyroidism among 5 are born to mother undergo thyroidectomy with L-tiroxina teraphy during the pregnancy. Then the newborns of thyroidectomized mothers also many years before the pregnancy must be considered high risk of developing neonatal hyperthyroidism because of long-lasting persistence of mother's TRAb. The neonatal hyperthyroidism, clinical and biochemical, appears later in newborns of mothers using antithyroid drugs. The pharmacological treatment of neonatal hyperthyroidism was difficult to standardize and highly individualized.

CONCLUSIONS

Although the neonatal hyperthyroidism is a very rare disease it is essential to apply specific protocol assistance, both during pregnancy and the neonatal period, in the presence of maternal TRAb positive for the risk of serious cardiovascular complications.