We report on a 35-year-old woman who presented at 36 weeks of gestation with headaches and arterial hypertension. She was discharged after ruling out pre-eclampsia. The next day she returned with worsening headaches and an onset of Horner’s syndrome. A magnetic resonance (MR) angiography showed extensive dissection of the right-sided internal carotid artery. Anticoagulation and antihypertensive therapies were initiated after delivery of the baby by caesarean. The patient recovered fully. Headache in pregnancy is not always due to pre-eclampsia. Carotid artery dissection (CAD) is a rare but severe cause of headache that typically presents with neck pain and focal neurologic symptoms. Once the diagnosis is established, an immediate treatment should be started in order to minimise damage, especially ischaemic lesions.