The prevalence of asthma among pregnant females is increasing. Asthma is one of the most common chronic medicalconditions that cause complications in pregnancy. There is evidence that asthma can adversely impact on pregnancy outcomes,and conversely that pregnancy may result in a change in the clinical status of a female with asthma. The aim this study was toknow prevalence of asthma exacerbation in pregnancy and the effects to infant and maternal in Sanglah General Hospital. Thisstudy is retrospective study to medical record of pregnancy patients delivery at Sanglah General Hospital. In this study we found1959 pregnancy patients and prevalence of asthma exacerbation was 0.71% (14 asthmatic patients) Proportion of pathologicdelivery, pre-eclampsia and congenital malformations of the fetus was lower in asthmatic group than in group without asthmabut not signi! cant. The mean of birth weight was lower in asthma group than in group without asthma (3107.14 ± 521.78 grams: 3306.70 ± 366.21 grams) p = 0.05 95%CI (-399.14 ? 0.012). The conclusion this study is prevalence of asthma exacerbationson pregnant females in Sanglah General Hospital was 0.71%. Birth weight both in pregnant females with asthma and pregnantfemales without asthma was in normal limit but trend was lower in pregnant females with asthma than pregnant females withoutasthma.