Secondary causes of hypertension in pregnancy
| Aetiology | Clinical assessment in pregnancy | Diagnosis and management in pregnancy |
|---|---|---|
| Coarctation | Upper limb hypertension Radio-/brachiofemoral delay Systolic murmur from associated bicuspid aortic valve Turner’s syndrome phenotype | Echo/MRI |
| Chronic kidney disease | Symptoms: oedema, arthralgia, rash, hair loss, visible haematuria, recurrent UTI and family history Renal bruit Urine dip Quantification of proteinuria Serum creatinine Kidney ultrasound for morphology and symmetry | >2+ blood or protein on urine dip warrants further assessment uACR >8 mg/mmol and uPCR >30 mg/mmol are abnormal in pregnancy Creatinine >77 μmol/L is abnormal in pregnancy6 Imaging of renal vasculature usually delayed until postpartum, provided safe blood pressure control can be achieved ACEi and ARB contraindicated due to fetotoxicity |
| Hyperaldosteronism / Conn’s syndrome | Hypokalaemia Treatment resistance | Gestational increases in renin and aldosterone prevent accurate interpretation Formal diagnosis usually delayed until postpartum, provided safe blood pressure control can be achieved Spironolactone contraindicated due to anti-androgenic fetal effects Limited data on the use of amiloride and eplerenone in pregnancy |
| Cushing’s syndrome | Phenotype: thin skin, bruising, striae, fat distribution, proximal weakness, elevated plasma glucose/early diagnosis of GDM | Phenotype overlaps with normal pregnancy Gestational increase in cortisol prevents accurate interpretation Formal diagnosis usually delayed until postpartum, provided safe blood pressure control can be achieved |
| Phaeochromocytoma/paraganglioma | Headache, sweating, tachycardia, anxiety Episodic hypertension | Urine and plasma metanephrine concentrations unaffected by pregnancy. Non-contrast MRI MIBG contraindicated due to placental transfer; maternal benefit of alpha-blockade outweighs risk; labetalol has insufficient alpha-blockade in isolation |
| Hyperparathyroidism | Nausea/hyperemesis, constipation, low mood, polyuria Serum calcium and PTH | Significant maternal (pancreatitis, kidney injury, nephrolithiasis, pre-eclampsia) and fetal (miscarriage, intrauterine death) risks warrant early diagnosis and support definitive surgical treatment in pregnancy |
ACEi = angiotensin converting enzyme inhibitor; ARB = angiotensin receptor blocker; Echo = echocardiography; GDM = gestational diabetes mellitus; MIBG = radioactive iodine metaiodobenzylguanidine; MRI = magnetic resonance imaging; PTH = parathyroid hormone; uACR = urinary albumin:creatinine ratio; uPCR = urinary protein:creatinine ratio; UTI = urinary tract infection.