Beyond the lungs: Alpha-1 antitrypsin's potential role in human gestation.

Alpha-1 antitrypsin (AAT) is an acute-phase protein with strong inhibitory activity towards proteolytic enzymes, mainly elastase but also trypsin, chymotrypsin and thrombin. The biological role of the protein and the effects of its deficiency have been subjects of scientific research for years, yet in many areas our knowledge remains incomplete. Alpha-1 antitrypsin deficiency (AATD), a defect in AAT synthesis and functionality, is one of the most frequently inherited genetic disorders among Caucasian populations. Its severe form is characterized by very low serum levels of AAT, and it most often affects the lungs (causing early-onset emphysema or chronic obstructive lung disease (COPD)) and/or liver (leading to jaundice and liver cirrhosis in children and adults). However, little is known about other possible clinical consequences of AAT deficiency. We discuss AAT's potential role in mechanisms regulating human fertility and gestation, with a particular emphasis on the clinical context and on indications for AATD diagnostic testing.