The Pompe Pregnancy Sub-Registry is a study designed to observe pregnant women with Pompe disease. Pompe disease is a genetic disorder that affects muscle strength and movement. The goal is to track how these women and their babies do during and after pregnancy. This study is observational, meaning doctors will watch and gather information but won't change any treatments. Women may receive standard care, which could include ERT (enzyme replacement therapy) with medicines like alglucosidase alfa or avalglucosidase alfa, but no new experimental drugs will be given.

• The study is both retrospective (looking at past data) and prospective (collecting new data going forward).
• To join, you must be enrolled in the main Pompe registry and provide consent.
• There are no exclusion criteria, so any pregnant woman with Pompe disease in the registry can participate.

Participation is encouraged for all pregnancies if you have more than one. The study aims to understand better pregnancy outcomes and infant growth in women with Pompe disease, with or without specific therapy.