Table 4 Baseline characteristics and outcome data in COVID-19 cases and matched controls.

From: The impact of COVID-19 on pregnancy outcomes in a diverse cohort in England

 

COVID-19 cases (n = 214)

Controls (n = 214)

p value

Baseline Characteristics

Maternal age (years)

30 (26–34)

30 (26–34)

0.91

Ethnicity

Asian

65 (30.4%)

65 (30.4%)

–

Black

37 (17.3%)

37 (17.3%)

–

Mixed

2 (0.9%)

2 (0.9%)

–

Other

19 (8.9%)

19 (8.9%)

–

White

89 (41.6%)

89 (41.6%)

–

Not recorded

2 (0.9%)

2 (0.9%)

–

Parity

1 (0–2)

1 (0–2)

0.30

BMI (kg/m2)

27.3 ± 6.1

27.1 ± 6.3

0.46

Diabetes in pregnancy

17 (7.9%)

17 (7.9%)

–

Hypertension at booking

7 (3.3%)

7 (3.3%)

–

Sex of baby

Male

119 (55.6%)

118 (55.1%)

0.60

Female

94 (43.9%)

96 (44.9%)

 

Indeterminate

1 (0.5%)

0 (0.0%)

 

Trimester at diagnosis

First

3 (1.4%)

–

–

Second

25 (11.7%)

–

–

Third

186 (86.9%)

–

–

Neonatal Outcomes

Mode of delivery

Spontaneous vaginal

105 (49.1%)

114 (53.3%)

0.70

Forceps

26 (12.2%)

30 (14.0%)

 

Ventouse

10 (4.7%)

8 (3.7%)

 

Emergency CS

46 (21.5%)

41 (19.2%)

 

Elective CS

27 (12.6%)

21 (9.8%)

 

Gestation at delivery (days)

275 (269–281)

278 (271–284)

0.002

Preterm birth

 < 37 weeks

27 (12.6%)

18 (8.4%)

0.16

 < 34 weeks

7 (3.3%)

3 (1.4%)

0.20

Iatrogenic (< 37 weeks)

21 (9.8%)

9 (4.2%)

0.02

Placental abruption

3 (1.4%)

1 (0.5%)

N/Aa

Stillbirth

1 (0.5%)

0 (0.0%)

N/Aa

Neonatal death

2 (0.9%)

2 (0.9%)

N/Aa

NICU admission

25 (11.7%)

30 (14.0%)

0.48

NICU length of stay (days)

6 (3–12) (n = 25)

3.5 (2–8) (n = 30)

0.25

Cord arterial pH

7.18 ± 0.09 (n = 82)

7.18 ± 0.08 (n = 98)

0.49

Cord arterial base deficit

7.0 ± 3.7 (n = 82)

7.4 ± 3.6 (n = 98)

0.75

Maternal Outcomes

Estimated blood loss (ml)

400 (300–700)

450 (300–700)

0.39

Maternal length of stay (days)

2 (1–4)

2 (1–4)

0.81

Pre-eclampsia

6 (2.8%)

8 (3.7%)

0.60

HDU admission

12 (5.6%)

12 (5.6%)

1.00

ICU admission

4 (1.9%)

0 (0.0%)

N/Aa

 

COVID-19 Cases (n = 91b)

Controls (n = 91b)

Significance (p value)

Growth

Birth weight (g)

3244 ± 616

3351 ± 584

0.12

Birth weight z-score

− 0.29 ± 1.20

− 0.36 ± 1.16

0.66

Fetal growth restriction

8 (8.8%)

9 (9.9%)

0.80

  1. Data are presented as median (IQR), mean ± SD, or number (%) as appropriate for data type and distribution. Comparisons were performed using the chi-squared test, paired and unpaired t-tests, Wilcoxon sign-rank test, and Mann–Whitney U test as appropriate.
  2. Significant values are in bold.
  3. CS Caesarean section, HDU High dependency unit, ICU Intensive care unit, NICU Neonatal intensive care unit.
  4. aInferential tests statistics are not reported where number of events was less than 5 in both groups.
  5. bOnly pregnancies where the time between a positive swab and delivery exceeded 14 days are included in analysis of fetal growth.
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