Hypertension in CKD Pregnancy: a Question of Cause and Effect (Cause or Effect? This Is the Question).

Chronic kidney disease (CKD) is increasingly encountered in pregnancy, and hypertension is frequently concomitant. In pregnancy, the prevalence of CKD is estimated to be about 3%, while the prevalence of chronic hypertension is about 5-8%. The prevalence of hypertension and CKD in pregnancy is unknown. Both are independently related to adverse pregnancy outcomes, and the clinical picture merges with pregnancy-induced hypertension and preeclampsia. Precise risk quantification is not available, but risks linked to CKD stage, hypertension, and proteinuria are probably multiplicative, each at least doubling the rates of preterm and early preterm delivery, small for gestational age babies, and related outcomes. Differential diagnosis (based upon utero-placental flows, fetal growth, and supported by serum biomarkers) is important for clinical management. In the absence of guidelines for hypertension in CKD pregnancies, the ideal blood pressure goal has not been established; we support a tailored approach, depending on compliance, baseline control, and CKD stages, with strict blood pressure monitoring. The choice of antihypertensive drugs and the use of diuretics and of erythropoiesis-stimulating agents (ESAs) are still open questions which only future studies may clarify.