A survey was posted to 27 women with acute porphyria about complications and outcome of pregnancy. Fifteen women returned the completed questionnaire and the pregnancies were characterised depending on the timing of diagnosis of porphyria. Four women were diagnosed with porphyria before the first pregnancy, five during a pregnancy and six after pregnancy. Five women were diagnosed with porphyria from family studies and the remaining ten were diagnosed when they presented with acute symptoms. There were a total of 33 pregnancies and 23 live births. Four women reported symptoms associated with porphyria during pregnancy. Two women received treatment with haem arginate during pregnancy with one of them having haem arginate therapy weekly with no adverse effect either to her or the baby. One woman had acute pain and skin symptoms during pregnancy but was not diagnosed until after delivery, and another reported acute symptoms during pregnancy. There were no differences, compared to the general population, between birth weight and miscarriage rate, and there were few obstetric complications with only one patient having pre-eclampsia at 37 weeks gestation. These results show that pregnancy is typically uncomplicated in acute porphyria, and that problems are more likely if the porphyria has not been diagnosed previously. We found that administration of haem arginate during pregnancy is safe and its continuous use during pregnancy has no detrimental effect on the outcome of pregnancy.