Lymphangioleiomyomatosis (LAM) is a rare lung disease affecting women. Following case reports that pregnancy exacerbates LAM, patients are frequently advised to avoid pregnancy. Our objective was to determine pregnancy and health outcomes in LAM to provide better evidence with which to council patients contemplating pregnancy. We surveyed 328 women with LAM regarding pregnancy outcomes, pulmonary function, subjective and psychological functioning, quality of life, dyspnoea and fatigue. Amongst childless women the main reason not to attempt pregnancy was based on concerns about potential effects of pregnancy on LAM. Almost two thirds of patients had been pregnant, the majority before LAM was diagnosed, in whom pregnancy outcome was generally favourable. Women diagnosed with LAM (n=15) during pregnancy had high rates of pneumothorax (67%), miscarriage (7%) and premature birth (47%). The group diagnosed with LAM before or during pregnancy (n=12) had lower mean FEV(1), FVC and DLCO after pregnancy compared with those diagnosed following pregnancy or never pregnant. There were no differences in subjective or psychological functioning, quality of life, dyspnoea or fatigue scores between groups. In newly diagnosed LAM patients there was a high incidence of premature birth and pneumothorax. These adverse outcomes may be a marker of aggressive LAM.