Gestational hypertension

The exact etiology of gestational hypertension remains unknown. It is thought that insulin resistance may mediate the clinical onset of hypertension in pregnancy.[6]Innes KE, Wimsatt JH, McDuffie R. Relative glucose tolerance and subsequent development of hypertension in pregnancy. Obstet Gynecol. 2001 Jun;97(6):905-10. http://www.ncbi.nlm.nih.gov/pubmed/11384694?tool=bestpractice.com

The pathophysiology of gestational hypertension is not completely understood. Blood pressure is usually elevated in pregnancy because of upregulation of the renin-angiotensin-aldosterone system, but this is balanced by a drop in the systemic vascular resistance (SVR) and cardiac output. In women with gestational hypertension, the SVR remains low but cardiac output tends to increase.[7]Vidaeff AC, Carroll MA, Ramin SM. Acute hypertensive emergencies in pregnancies. Crit Care Med. 2005 Oct;33(suppl 10):S307-12. http://www.ncbi.nlm.nih.gov/pubmed/16215352?tool=bestpractice.com

It is unclear whether gestational hypertension and preeclampsia represent distinct pathologies or are varying aspects along a single pathophysiologic spectrum.[8]Wolf M, Sandler L, Jimenez-Kimble R, et al. Insulin resistance but not inflammation is associated with gestational hypertension. Hypertension. 2002 Dec;40(6):886-91. https://www.ahajournals.org/doi/10.1161/01.HYP.0000042085.65467.9F http://www.ncbi.nlm.nih.gov/pubmed/12468574?tool=bestpractice.com

American College of Obstetrics and Gynecology (ACOG) practice bulletin 222​[1]American College of Obstetricians and Gynecologists. ACOG practice bulletin no. 222: gestational hypertension and preeclampsia. Jun 2020 [internet publication]. https://www.acog.org/clinical/clinical-guidance/practice-bulletin/articles/2020/06/gestational-hypertension-and-preeclampsia http://www.ncbi.nlm.nih.gov/pubmed/32443077?tool=bestpractice.com ​

• Gestational hypertension is defined as a systolic blood pressure (BP) of 140 mmHg or more or a diastolic BP of 90 mmHg or more, or both, on two occasions at least 4 hours apart after 20 weeks' gestation in a woman with previously normal BP.

• Hypertension in pregnancy is considered severe if the systolic BP level reaches 160 mmHg or the diastolic BP level reaches 110 mmHg, or both. If faced with severe hypertension, the diagnosis may need to be confirmed within a shorter interval (minutes) than 4 hours, to facilitate timely antihypertensive therapy. These women should be diagnosed with preeclampsia with severe features.

• Gestational hypertension is diagnosed if hypertension without proteinuria or severe features develops after 20 weeks' gestation and BP levels return to normal in the postpartum period.

• Gestational hypertension has similarities with preeclampsia; the management of gestational hypertension and that of preeclampsia without severe features is similar in many aspects, and both require enhanced surveillance.

• All hypertensive disorders of pregnancy, including gestational hypertension, are associated with adverse pregnancy outcomes and long-term risk of cardiovascular disease.

See Pre-eclampsia.

See also HELLP syndrome.