Thanks for your question on HCM. I advice you to consult pulmonologist befire planning pregnancy and get done 1. HRCT thorax 2. PFT (pulmonary function test). Both these investigations are needed to know about extent of the disease and functions of the lung. If only small part of lung is involved and PFT is good in terms of lung capacity and reserve than no need to worry much. She can be pregnant before fear. But if large part of lung is involved and lung functions are highly compromised than pregnancy can be dangerous. So better to consult pulmonologist and discuss in depth about these. You can also give her respiratory vaccines like pneumpcoccal and influenza before pregnancy to prevent future lung infections. Because respiratory infection is the most common cause for hemoptysis (blood in sputum).