Headaches in Pregnancy - Podcast Version 0:00 / 0:00 1x 0.25x 0.5x 0.75x 1x 1.25x 1.5x 1.75x 2x Headaches are a very common presenting complaint in pregnancy, with over a third of women affected. Similar to the non-pregnant population primary headaches account for most cases, however at least a third of gravid headaches are secondary to other pathologies. Fortunately, the majority of these have benign causes like viral infection and sinusitis but due to the significant morbidity and mortality associated with certain conditions in pregnancy all cases should be taken seriously, and recognition of red flags is key. Primary headaches in pregnancy Most headaches in pregnant women have no sinister underlying pathology, and migraine and tension-type headache are the most prevalent diagnoses in early pregnancy (it is worth nothing that migraines pre-pregnancy are a risk factor for hypertension and pre-eclampsia). Primary headaches peak in women of reproductive age anyway due to the impact of hormones, however 75% of women who experience benign headaches pre-pregnancy find they reduce in the antenatal period. However, it is important to note that previously diagnosed primary headache disorders can present with different symptoms in pregnancy so all need to be fully assessed. Secondary headaches in pregnancy Hypertensive Pre-eclampsia and eclampsia The presentation is variable but most commonly a worsening bilateral pulsatile headache, which can affect one or more scalp areas. Pain can be worse with exercise and doesn’t improve with mild analgesics. Visual disturbance may be present, along with other signs of end organ damage or seizures. Due to the heterogenous presentation any woman over 20 weeks gestation presenting with a headache should have a blood pressure measurement and urine dip to rule out pre-eclampsia. Posterior reversible encephalopathy syndrome A clinical phenomenon comprising a progressive headache, reduced consciousness, visual disturbance, seizures, vomiting and focal neurology. Women usually have a concomitant gravid hypertensive disorder or renal failure, and the syndrome is accompanied by a characteristic MRI appearance which can persist beyond the resolution of symptoms. Vascular Ischaemic stroke Around a third of strokes have transient headache as a presenting feature, but neurological signs are much more common and allow easier recognition. Diagnosis and treatment are similar to non-pregnant stroke patients although pregnancy is a relative contraindication to thrombolysis so a senior MDT decision is required. Subarachnoid haemorrhage As in non-pregnant patients SAH is characterised by a thunderclap headache, vomiting and loss of consciousness. Risk of SAH is around 20 times higher in the postnatal period compared to the general population. Cerebral venous sinus thrombosis There is no specific pattern of symptoms for CVT, which is caused by blockage of blood draining from the cerebral sinuses, mostly commonly patients present with diffuse worsening headaches but not exclusively. Usually patients also have focal neurology, signs of raised intracranial pressure or subacute encephalopathy. The other risk factors for VTE still apply in the pregnant population and are assessed at set times throughout pregnancy so should be taken into account when considering CVT. Patients with suspected CVT should urgent CT or MR angiography and treated with anticoagulants. Reversible cerebral vasoconstriction syndrome Commonly a recurrent, sudden, severe headache starting in the first week postnatally and triggered by exercise, sexual intercourse, straining or strong emotion. Cervical artery dissection A rare diagnosis which most commonly occurs due to pressure in labour and is accompanied by a sudden severe unilateral headache. Space-occupying lesions Brain neoplasms must be at least 1cm in size to cause mass effect symptoms, and certain types can enlarge in pregnancy, meaning this may be when a woman presents with signs of intracranial hypertension. The most common primary brain tumours diagnosed in pregnant women are pituitary adenomas, meningiomas and glial tumours. Although much rarer, pregnancy-associated tumours like choriocarcinoma can also metastasise to the brain, causing pain, dizziness and visual loss. Red Flags Researchers have studied primary and secondary headaches to try and find strong differentiating factors, however this has proven difficult. It is thought that unilateral headaches are more likely to be benign but features which are common in primary headaches, such as visual and sensory disturbance, can also occur with more sinister causes. Therefore, a thorough history and examination, including a full neurological examination, along with basic investigations (blood pressure, urinalysis, bloods, fundoscopy) are key to identifying women who need further investigations. Specific to pregnant patients: Rapid onset (reaches peak within 5 minutes) or very severe No headache history pre-pregnancy or new type of headache Varies with posture Wakes the patient from sleep Triggered by exertion Third trimester Hypertension Proteinuria Deranged blood results – LFTs, platelets Common to the pregnant and non-pregnant populations: Fever New neurological symptoms Signs of raised intracranial pressure – nausea, papilloedema Comorbidities – cancer, HIV, pituitary disorders, VTE risk factors Investigations to consider when suspecting significant pathology CT or MRI head – CT head commonly first line as more readily available and the fetal risk from a maternal CT head is actually quite low. Iodinated contrast can affect the foetal thyroid so should be avoided if possible – if it cannot be avoided a heel prick test of the baby’s thyroid function should be done after delivery. CT or MR angiography Carotid artery ultrasound Lumbar puncture EEG D-dimers are usually avoided in pregnancy as they can be raised due to changes in the coagulation pathways – occasionally can be useful to rule out thrombotic conditions in patients presenting with an isolated headache but not a common investigation General management of headache in pregnancy Management heavily depends on the suspected underlying cause Conservative – minimise triggers, physical activity, regular sleeping patterns, healthy diet, acupuncture, yoga Analgesia – paracetamol is the safest option in pregnancy, with codeine and tramadol as second-line options. NSAIDs are generally avoided in pregnancy due to the risk of early miscarriage and premature closure of the ductus arteriosus, however there are some circumstances in which they are used before 32 weeks but this decision should only come from a senior clinician after discussion with the patient. Prophylaxis – propranolol is first-line for migraine prevention with amitriptyline as an alternative Key points Headaches are very common in pregnancy and most are benign but the significant consequences of certain conditions mean all patients should have thorough history and examination Migraine, with or without aura, and tension-type headaches are the commonest forms of primary headache Viral infections are the most frequent secondary headache but other important diagnoses to consider include hypertensive disorders of pregnancy, stroke, cerebral venous thrombosis, intracranial haemorrhage and space-occupying lesion Early imaging if a sinister cause is suspected is vital for treatment to be most effective References (1) Raffaelli, B., Siebert, E., Körner, J. et al. Characteristics and diagnoses of acute headache in pregnant women – a retrospective cross-sectional study. J Headache Pain 18, 114 (2017). (2) Sandoe, C.H., Lay, C. Secondary Headaches During Pregnancy: When to Worry. Curr Neurol Neurosci Rep 19, 27 (2019). (3) Negro A, Delaruelle Z, Ivanova TA, et al. Headache and pregnancy: a systematic review. J Headache Pain. 2017;18(1):106. (4) Hamilton K. Secondary Headaches During Pregnancy and the Postpartum Period. Practical Neurology. May 2020 (5) Wiles R, Hankinson B, Benbow E, Sharp A. Making decisions about radiological imaging in pregnancy BMJ 2022; 377 :e070486 doi:10.1136/bmj-2022-070486 Frequent questions What are the most common types of headaches experienced during pregnancy? Most headaches in pregnant women are classified as primary headaches, with migraine and tension-type headaches being the most prevalent. While these headaches are often benign, they can present differently during pregnancy, necessitating thorough assessment. What are the red flags associated with headaches in pregnant women? Red flags include sudden onset severe headaches, headaches that worsen with posture, or those that disrupt sleep. Additional concerning signs are hypertension, proteinuria, and new neurological symptoms, which warrant immediate evaluation. How can pre-eclampsia present in pregnant women experiencing headaches? Pre-eclampsia commonly manifests as a worsening bilateral pulsatile headache, often accompanied by visual disturbances and signs of end organ damage. Any woman over 20 weeks gestation presenting with a headache should have her blood pressure and urine checked to rule out this condition. What is the significance of secondary headaches in pregnancy? Secondary headaches can indicate serious underlying conditions, such as hypertensive disorders, stroke, or cerebral venous sinus thrombosis. Although many headaches are benign, it is crucial to investigate any secondary causes to ensure appropriate management. What conservative management strategies are recommended for headaches during pregnancy? Conservative strategies include minimising headache triggers, maintaining regular sleep patterns, and engaging in healthy activities like yoga and acupuncture. Paracetamol is the safest analgesic option, while other medications should be used cautiously and under medical supervision. Rate This Article