HELLP syndrome occurs in approximately 1 to 8 per 1000 pregnancies.[9]Haram K, Svendsen E, Abildgaard U. The HELLP syndrome: clinical issues and management. BMC Pregnancy Childbirth. 2009 Feb 26;9:8.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2654858/?tool=pubmed
http://www.ncbi.nlm.nih.gov/pubmed/19245695?tool=bestpractice.com
In pregnancies complicated by pre-eclampsia, laboratory findings of HELLP are present in 2% to 20% of cases; in those complicated by eclampsia, HELLP is present in 10% to 30% of cases.[1]Sibai BM, Ramadan MK, Usta I, et al. Maternal morbidity and mortality in 442 pregnancies with hemolysis, elevated liver enzymes and low platelets (HELLP syndrome). Am J Obstet Gynecol. 1993 Oct;169(4):1000-6.
http://www.ncbi.nlm.nih.gov/pubmed/8238109?tool=bestpractice.com
[2]Martin JN Jr, Blake PG, Perry KG Jr, et al. The natural history of HELLP syndrome: patterns of disease progression and regression. Am J Obstet Gynecol. 1991 Jun;164(6 Pt 1):1500-9; discussion 1509-13.
http://www.ncbi.nlm.nih.gov/pubmed/2048596?tool=bestpractice.com
[10]Sibai BM. Diagnosis and management of gestational hypertension and preeclampsia. Obstet Gynecol. 2003 Jul;102(1):181-92.
http://www.ncbi.nlm.nih.gov/pubmed/12850627?tool=bestpractice.com
[11]Ducarme G, Bernuau J, Luton D, et al. Liver and preeclampsia [in French]. Ann Fr Anesth Reanim. 2010 Apr;29(4):e97-103.
http://www.ncbi.nlm.nih.gov/pubmed/20347556?tool=bestpractice.com
[12]Keiser SD, Owens MY, Parrish MR, et al. HELLP syndrome with and without eclampsia. Am J Perinatol. 2011 Mar;28(3):187-94.
http://www.ncbi.nlm.nih.gov/pubmed/20827656?tool=bestpractice.com
[13]Noubiap JJ, Bigna JJ, Nyaga UF, et al. The burden of hypertensive disorders of pregnancy in Africa: a systematic review and meta-analysis. J Clin Hypertens (Greenwich). 2019 Apr;21(4):479-88.
https://onlinelibrary.wiley.com/doi/full/10.1111/jch.13514
http://www.ncbi.nlm.nih.gov/pubmed/30848083?tool=bestpractice.com
[14]Kongwattanakul K, Saksiriwuttho P, Chaiyarach S, et al. Incidence, characteristics, maternal complications, and perinatal outcomes associated with preeclampsia with severe features and HELLP syndrome. Int J Womens Health. 2018;10:371-7.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6054275
http://www.ncbi.nlm.nih.gov/pubmed/30046254?tool=bestpractice.com
Most patients present between 27 and 37 weeks' gestation. In 15% to 30%, HELLP is either expressed postpartum or progresses postpartum.[1]Sibai BM, Ramadan MK, Usta I, et al. Maternal morbidity and mortality in 442 pregnancies with hemolysis, elevated liver enzymes and low platelets (HELLP syndrome). Am J Obstet Gynecol. 1993 Oct;169(4):1000-6.
http://www.ncbi.nlm.nih.gov/pubmed/8238109?tool=bestpractice.com
[5]Martin JN Jr, Rinehart BK, May WL, et al. The spectrum of severe preeclampsia: comparative analysis by HELLP (hemolysis, elevated liver enzyme levels, and low platelet count) syndrome classification. Am J Obstet Gynecol. 1999 Jun;180(6 Pt 1):1373-84.
http://www.ncbi.nlm.nih.gov/pubmed/10368474?tool=bestpractice.com
HELLP is more common in white people in the US than in African-Americans or Hispanics. Although advanced maternal age (>35 years) is a significant risk factor, the mean maternal age at presentation is 23 to 25 years. About 10% of patients have multiple gestations.[1]Sibai BM, Ramadan MK, Usta I, et al. Maternal morbidity and mortality in 442 pregnancies with hemolysis, elevated liver enzymes and low platelets (HELLP syndrome). Am J Obstet Gynecol. 1993 Oct;169(4):1000-6.
http://www.ncbi.nlm.nih.gov/pubmed/8238109?tool=bestpractice.com
[5]Martin JN Jr, Rinehart BK, May WL, et al. The spectrum of severe preeclampsia: comparative analysis by HELLP (hemolysis, elevated liver enzyme levels, and low platelet count) syndrome classification. Am J Obstet Gynecol. 1999 Jun;180(6 Pt 1):1373-84.
http://www.ncbi.nlm.nih.gov/pubmed/10368474?tool=bestpractice.com