Trimester and severity of SARS-CoV-2 infection during pregnancy and risk of hypertensive disorders in pregnancy

Figures & data

Table 1. Maternal and reproductive characteristics of SARS-CoV-2 cohort and unexposed cohort, boston medical center.

	SARS-CoV-2 Cohort n=205		Unexposed Cohort n=2776
	n	%	n	%
Maternal age (years)
<20	15	7.3	157	5.7
21–25	48	23.4	474	17.1
26–30	39	19.0	828	29.8
31–35	57	27.8	809	29.1
36+	46	22.4	508	18.3
Maternal race/Ethnicity
Non-Hispanic White	10	4.9	345	12.4
Non-Hispanic Black	47	22.9	1016	36.6
Hispanic	132	64.4	1027	37.0
Asian	7	3.4	107	3.9
Unknown	9	4.4	281	10.1
Gravidity
1	54	26.3	771	27.8
2	50	24.4	738	26.6
≥3	101	49.3	1267	45.6
Parity
0	78	38.1	1069	38.5
1	56	27.3	884	31.8
2	42	20.5	517	18.6
≥3	29	14.1	306	11.0
Pre/Early pregnancy (<20 weeks) body mass index (kg/m^2)^a
Underweight/normal (<25 kg/m^2)	38	22.6	519	35.2
Overweight (25–29.9 kg/m^2)	59	35.1	445	30.2
Obese (≥30 kg/m^2)	71	42.3	511	34.6
Missing	37		1301
Tobacco smoking
Current	2	1.0	138	5.0
Former	13	6.3	264	9.5
Never	185	90.2	2374	85.5
Unknown	5	2.4	58	2.1
Insurance
Public	174	84.9	2162	77.9
Private	28	13.7	533	19.2
Other/Unknown	3	1.5	81	2.9
Other medical conditions
Pre-existing or gestational diabetes	29	14.2	275	9.9
Chronic hypertension	16	7.8	111	4.0
Chronic asthma	16	7.8	103	3.7
Delivery/Infant Characteristics
Mode of delivery
Cesarean section	69	33.7	983	35.4
Vaginal delivery	135	65.9	1793	64.6
Preterm birth (< 37 weeks)	27	13.2	299	10.8
Multiple birth	5	2.4	52	1.9

^aPercent calculated excluding patients with missing BMI from the denominator.

Table 2. Crude and adjusted risk ratios and 95% confidence intervals for SARS-CoV-2 infection and hypertensive disorder of pregnancy overall and by subtype.

	SARS-CoV-2 Cohort N=205		Unexposed Cohort N=2,776
	n	%	n	%	Crude RR (95% CI)	Adjusted RR^a (95% CI)
Any HDP	48	23.4	536	19.3	1.21 (0.94, 1.57)	1.17 (0.90, 1.51)
HDP Type
Gestational hypertension	25	12.2	322	11.6	1.09 (0.75, 1.60)	1.08 (0.74, 1.58)
Preeclampsia	23	11.2	214	7.7	1.46 (0.97, 2.18))	1.33 (0.89, 1.98)

^aAdjusted for maternal age and comorbidity index (preexisting hypertension, diabetes, or asthma).

Table 3. Crude risk ratios and 95% confidence intervals for SARS-CoV-2 infection and hypertensive disorder of pregnancy overall and by subtype, by race/ethnicity.

	SARS-CoV-2 cohort	Unexposed cohort	Crude RR (95% CI)
Black, non-Hispanic	n=47	n=1016
Any HDP	13	227	1.24 (0.77, 1.99)
Gestational hypertension	5	137	0.87 (0.38, 1.99)
Preeclampsia	8	90	1.92 (0.99, 3.70)
White, non-Hispanic	n=10	n=345
Any HDP	3	72	1.44 (0.55, 3.79)
Gestational hypertension	2	50	n/c
Preeclampsia	1	22	n/c
Hispanic	n=132	n=1027
Any HDP	28	174	1.25 (0.88, 1.79)
Gestational hypertension	15	95	1.26 (0.73, 2.24)
Preeclampsia	13	79	1.28 (0.73, 2.24)

Figure 1. Risk ratios and 95% confidence intervals for gestational week of infection and hypertensive disorders of pregnancy, restricted cubic spline.

Table 4. Crude and adjusted risk ratios and 95% confidence intervals for SARS-CoV-2 infection and hypertensive disorders of pregnancy, by trimester and severity, SARS-CoV-2 cohort.

	SARS-CoV-2 Cohort n=205		HDP n=48		No HDP n=157		Crude RR (95% CI)	Adjusted RR (95% CI) ^a
Trimester of infection	n	%	n	%	n	%
1st Trimester	23	11.2	6	12.5	17	10.8	1.26 (0.58, 2.74)	1.09 (0.52, 2.37)
2nd Trimester	66	32.2	18	37.5	48	30.6	1.32 (0.78, 2.24)	1.30 (0.77, 2.21)
3rd Trimester	116	56.6	24	50.0	92	58.6	1.0 (Reference)	1.0 (Reference)
Severity of infection
Asymptomatic	29	14.2	3	6.3	26	16.6	1.0 (Reference)	1.0 (Reference)
Mild	121	59.3	27	56.3	94	59.9
Moderate	30	14.7	8	16.6	22	14.0	1.33 (0.68, 2.62)	1.40 (0.73, 2.68)
Severe	24	11.8	9	18.8	15	9.6	1.88 (1.02, 3.44)	1.74 (0.99, 3.05)

HDP: hypertensive disorders of pregnancy.

^aAdjusted for maternal age and comorbidity index (preexisting hypertension, diabetes, or asthma).

Table 5. Risk ratios and 95% confidence intervals for trimester of SARS-CoV-2 and hypertensive disorders of pregnancy, stratified by symptom severity, SARS-CoV-2 cohort.

			Asymptomatic/Mild symptoms Asymptomatic/Mild symptoms = 150
	1st Trimester n = 20		2nd Trimester n = 44		3rd Trimester n = 86
	n	%	n	%	n	%
HDP	6	30.0	9	20.5	15	17.4
No HDP	14	70.0	35	79.5	71	82.6
RR (95% CI)^a	1.70 (0.77, 3.77)		1.20 (0.58, 2.52)		1.0 (reference)
	Moderate/Severe symptoms n = 54
	1st Trimester n = 3		2nd Trimester n = 21		3rd Trimester n = 30
	n	%	n	%	n	%
HDP	0	0.0	8	38.1	9	30.0
No HDP	3	100.0	13	61.9	21	70.0
RR (95% CI)^a	n/c		1.20 (0.57, 2.50)		1.0 (reference)

n/c: not calculated

^aAdjusted for maternal age and comorbidity index.