THE CONTEXT
The passage relates fetal and perinatal risks to the severity of chronic hypertension and outlines blood pressure treatment and obstetric management.
Fetal and perinatal risks
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Chronic placental insufficiency makes fetal growth restriction likely, and preterm birth is high.
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In milder disease with blood pressure below 160/100 mm Hg, perinatal loss is about 10%.
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When blood pressure exceeds 160/100 mm Hg, perinatal loss increases three to four times and rises further if pre-eclampsia develops.
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The risk of placental abruption is high, with a stated range of 0.5–10%.
Management goals and preconception assessment
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Management aims to stabilize blood pressure below 160/100 mm Hg, prevent superimposed pre-eclampsia, monitor maternal and fetal wellbeing and deliver at the optimal time.
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Preconception evaluation and counseling are essential to assess the cause and severity of hypertension and the possible pregnancy outcome.
Antihypertensive treatment
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Routine antihypertensive treatment is not favored in the passage: lowering blood pressure may benefit the mother while reducing placental perfusion to the detriment of the fetus.
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Labetalol, nifedipine or hydralazine should be used when blood pressure rises beyond 160/100 mm Hg to prevent target organ damage, including stroke and renal or cardiac failure.
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For women taking these drugs before pregnancy, doses require adjustment during pregnancy, especially in midpregnancy when blood pressure tends to fall.
Obstetric and postpartum management
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In mild cases, spontaneous labor is awaited.
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In severe or complicated cases, the stated aim is to continue pregnancy to at least 34 weeks; otherwise, pregnancy is continued up to the 37th week to attain fetal maturity before delivery.
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Blood pressure control is needed for the first 24 hours postpartum.