In cases of recurrent attacks of acute porphyria during pregnancy, prophylactic administration of heme arginate should be considered. Clinical and biochemical monitoring of the disease and a close collaboration with a porphyria expert center are crucial. Acute intermittent porphyria (AIP) is the most common of the acute hepatic porphyrias, with a European prevalence reported to be approximately 5.4:1 000 000. 1 Acute intermittent porphyria has a low clinical penetrance, and the incidence of overt disease in European countries is estimated to be 0.13:1 000 000. 1 Symptoms rarely develop before puberty 2 and include episodic acute attacks of neurovisceral pain, peripheral neuropathy, hyponatremia, autonomic nervous system dysfunction which, if untreated, can be life-threatening. Women are far more likely than men to have clinical manifestations of the disease, and they are usually more seriously affected. 3,4 Symptoms are associated with endogenous or exogenous fluctuations in progesterone levels-intake of contraceptives, pregnancy, during the luteal phase of their menstrual cycle, when progesterone levels are increased. 3 Pregnancy involves a unique and unprecedented increase in estrogen and progesterone levels and those hormonal changes can trigger disease manifestations in women with AIP. In the past, pregnancy was associated with a significant morbidity for women with AIP 5,6 and there still are numerous