Pulmonary hypertension (PH) is reported to he a contraindication to bronchoscopic lung biopsy (BLB) because of the risk of uncontrolled hemorrhage. A prospective double-blinded study was designed to determine this risk in 50 patients with interstitial lung disease (ILD) with no clinical or radio-graphic evidence of PH who underwent BLB at Brooke Army Medical Center, a 450-bed teaching hospital. Before BLB. patients undentent Doppler flow echocardiography to determine pulmonary artery (PA) pressures and the size of the right atrium and right ventricle PH was defined as a systolic PA pressure >30 mmHg or evidence of right-sided chamber enlargement if no PA pressure could be determined. Overt bleeding during BLB was measured and additional blood loss was quantitated by comparing the hematocnts of the bronchial washings and the peripheral blood. Blood loss (in mL) was defined as: minimal. ≤10: mild. 11–25; moderate. 26–50; and severe. >50. Twenty-eight patients had no echocardiographic evidence of PH; only I had mild hemorrhage Twenty-two patients had evidence of PH; I patient had moderate hemorrhage. There was no significant difference (p = 0.9) in bleeding between the two groups; patients with PH had a mean blood loss of 2.0 ± 6.2 mL and patients without PH had a mean blood loss of 1.8 ± 3.8 mL. These data reveal that latent PH was present in 44% of our patients undergoing BLB for ILD but there was no increase in bleeding complications in this group.