Incidence, characteristics, maternal complications, and perinatal outcomes associated with preeclampsia with severe features and HELLP syndrome

Figures & data

Table 1 Characteristics of the preeclamptic women at baseline

Characteristics	N=213
Age – yearsa	29.0±6.1
Age group – n (%)
<20 years	19 (8.9)
20–34 years	161 (75.6)
≥35 years	33 (15.5)
Median pre-pregnancy BMI (IQR) – kg/m^2	21.9 (20.0–25.8)
BMI category – n (%)
<18.5 (under weight)	29 (14.0)
18.5–24.9 (normal weight)	119 (57.5)
25–29.9 (pre-obese)	36 (17.4)
≥30 (obesity)	23 (11.1)
Median gestational weight gain (IQR) – kg	14.7 (10.2–9.1)
Nulliparous – no (%)	106 (49.8)
In vitro fertilization method – n (%)	4 (1.9)
Multiple pregnancy – n (%)	11 (5.2)
History of previous preeclampsia – n (%)	11 (5.2)
Family history of hypertension in first-degree relative – n (%)	47 (22.6)
Underlying medical conditions
Connective tissue diseaseb – n (%)	10 (4.7)
Preexisting and type I diabetes mellitus – n (%)	9 (4.2)
Kidney diseases – n (%)	6 (2.8)

Notes:

a Values are mean ± SD.

b Connective tissue diseases are the systemic lupus erythematosus and antiphospholipid syndrome.

Abbreviations: BMI, body mass index; IQR, interquartile range.

Table 2 Diagnosis and delivery characteristics of the preeclamptic women

Characteristics	N=213
Diagnosis – n (%)
Preeclampsia with severe feature	107 (50.2)
Nonsevere feature preeclampsia	90 (42.3)
HELLP	16 (7.5)
Gestational age at diagnosis (completed week) – n (%)
GA <34 (early-onset PE)	58 (27.2)
GA ≥34 (late-onset PE)	155 (72.8)
Gestational age at delivery (completed week) – n (%)
GA <28 weeks	16 (7.5)
GA 28–<34 weeks	30 (14.1)
GA 34–<37 weeks	51 (23.9)
GA ≥37 weeks	116 (54.5)
Route of delivery – n (%)
Primary cesarean section	139 (65.3)
Repeated cesarean section	21 (9.9)
Vaginal delivery	47 (22.1)
Operative vaginal delivery	6 (2.8)
Nonreassuring fetal status – n (%)	34 (16)

Abbreviations: HELLP, hemolysis, elevated liver enzyme levels, and low platelet levels; GA, gestational age; PE, preeclampsia.

Table 3 Comparisons of characteristics between nonsevere preeclampsia versus preeclampsia with severe features and HELLP syndrome

Characteristics	Nonsevere feature preeclampsia (N=107)	Preeclampsia with severe features and HELLP (N=106)	p-value
Advanced maternal age – n (%)a	12 (11.2)	21 (19.8)	0.086
Median pre-pregnancy BMI (IQR) – kg/m^2	22.4 (20.3–26.6)	21.6 (19.6–24.8)	0.017
Median gestational weight gain (IQR) – (kg)	17 (12.1–20.0)	13 (9.0–18.2)	0.008
Nulliparous – n (%)	56 (52.3)	50 (47.2)	0.5363
In vitro fertilization method – n (%)	2 (1.9)	2 (1.9)	>0.999
Multiple pregnancy – n (%)	7 (6.5)	4 (3.8)	0.367
History of previous preeclampsia – n (%)	6 (5.7)	5 (4.8)	0.769
Family history of hypertension in first-degree relative – n (%)	21 (20.0)	26 (25.2)	0.366
Underlying medical conditions	10 (9.5)	15 (14.2)	0.335
Connective tissue diseaseb – n (%)	4 (3.7)	6 (5.7)	0.529
Preexisting and type I diabetes mellitus – n (%)	4 (3.7)	5 (4.8)	0.734
Kidney diseases – n (%)	2 (1.9)	4 (3.8)	0.423
Median gestational age at diagnosis	37 (36–39)	34 (29–37)	<0.001
Early-onset preeclampsia (,34 weeks)	12 (11.2)	46 (43.4)
Late-onset preeclampsia ($34 weeks)	95 (88.8)	60 (56.6)
Median gestational age at delivery (weeks)	37 (37–39)	35 (30–37)	<0.001
<28 weeks	1 (0.9)	15 (14.2)
28–<34 weeks	5 (4.7)	25 (23.6)
34–<37 weeks	19 (17.8)	32 (30.2)
≥37 weeks	82 (76.6)	34 (32.1)
Primary cesarean section – n (%)	64 (59.8)	75 (70.8)	0.135
Oligohydramnios – n (%)	26 (24.3)	59 (55.7)	<0.001
Nonreassuring fetal status – n (%)	15 (20.0)	19 (22.9)	0.437
Fetal growth restriction – n (%)	25 (23.4)	64 (60.4)	<0.001
Mean birth weight (g)c	2,747.9 (768.2)	1,858.7 (861.1)	<0.001

Notes:

a Advanced maternal age is age of women 35 years or older.

b Connective tissue diseases are the systemic lupus erythematosus and antiphospholipid syndrome.

c Values are mean ± SD. Data presented as median (25th–75th percentile) because data are not in normal distribution, on the basis of the Wilcoxon rank-sum test result.

Abbreviations: BMI, body mass index; HELLP, hemolysis, elevated liver enzyme levels, and low platelet levels; IQR, interquartile range.

Table 4 Comparison of maternal complications between nonsevere preeclampsia versus preeclampsia with severe features and HELLP syndrome

Characteristics	Nonsevere feature preeclampsia (N=107)	Preeclampsia with severe features and HELLP (N=106)	p-value
Postpartum hemorrhage – n (%)	11 (10.3)	10 (9.4)	0.836
Blood transfusion – n (%)	1 (0.9)	12 (11.3)	0.013
Placental abruption – n (%)	0 (0)	3 (2.8)	–
Heart failure – n (%)	0 (0)	1 (0.9)	–
ICU admission – n (%)	1 (0.9)	7 (6.6)	0.062

Note: Postpartum hemorrhage defined as estimated blood loss $500 mL.

Abbreviations: HELLP, hemolysis, elevated liver enzyme levels, and low platelet levels; ICU, intensive care unit.

Table 5 Comparison of neonatal complications between nonsevere preeclampsia versus preeclampsia with severe features and HELLP syndrome

Characteristics	Nonsevere feature preeclampsia (N=114)	Preeclampsia with severe features and HELLP (N=110)	p-value
Low birth weight – n (%)	40 (35.1)	81 (74.6)	<0.001
Birth asphyxia – n (%)	5 (4.4)	20 (18.2)	0.001
NICU admission – n (%)	8 (7.0)	34 (30.9)	<0.001
Resuscitation – n (%)	18 (15.8)	47 (42.7)	<0.001
Stillbirth – n (%)	0 (0)	3 (2.7)	–
Intrapartum death – n (%)	3 (2.6)	7 (6.4)	0.190

Notes: Birth asphyxia defined as Apgar score <7 at 5 minutes. Low birth weight defined as birth weight <2,500 g.

Abbreviations: HELLP, hemolysis, elevated liver enzyme levels, and low platelet levels; NICU, neonatal intensive care unit.