Table 1 Baseline characteristics of the study population in different immunity response group at one week after second dose.

From: COVID-19 mRNA vaccine-mediated antibodies in human breast milk and their association with breast milk microbiota composition

Variables

Overall (N = 43)

Low-IgA subjects (N = 25)

High-IgA subjects (N = 18)

P value

Maternal age (years)

   

0.250

 Median (IQR)

36.0 (31.0,39.0)

37.0 (32.0,39.0)

32.0 (30.3,37.8)

 

Gestational age (weeks)

   

0.960

 Median (IQR)

38.9 (38.0, 39.7)

38.9 (38.0, 39.7)

38.9 (38.0, 39.8)

 

Lactation stage at baseline (weeks)

   

0.971

 Median (IQR)

36.6 (20.3, 47.3)

36.6 (26.3, 45.9)

35.9 (17.2, 57.3)

 

Infant’s birth weight (kg)

   

0.658

 Median (IQR)

3.2 (3.1, 3.6)

3.2 (3.0, 3.6)

3.2 (3.0, 3.6)

 

Total number of previous children

   

0.213

 0

3 (7.0)

3 (12.0)

0 (0)

 

 1

20 (46.5)

12 (48.0)

8 (44.4)

 

 2

15 (34.9)

6 (24.0)

9 (50.0)

 

 3

5 (11.6)

4 (16.0)

1 (5.6)

 

Delivery type

   

0.414

 Spontaneous vaginal delivery

13 (30.2)

5 (20.0)

8 (44.4)

 

 Assisted vaginal delivery

3 (7.0)

2 (8.0)

1 (5.6)

 

 Planned C-section

19 (44.2)

13 (52.0)

6 (33.3)

 

 Emergency C- section

8 (18.6)

5 (20.0)

3 (16.7)

 

Labor induced

   

1

 No

28 (65.1)

16 (64.0)

12 (66.7)

 

 Yes

15 (34.9)

9 (36.0)

6 (33.3)

 

Epidural anesthesia use

   

0.057

 No

25 (58.1)

11 (44.0)

14 (77.8)

 

 Yes

17 (39.5)

13 (52.0)

4 (22.2)

 

 Missing

1 (2.3)

1 (4.0)

0 (0)

 

Intramuscular analgesia use

   

0.516

 No

31 (72.1)

19 (76.0)

12 (66.7)

 

 Yes

12 (27.9)

6 (24.0)

6 (33.3)

 

Infant’s sex

   

0.765

 Female

25 (58.1)

14 (56.0)

11 (61.1)

 

 Male

18 (41.9)

11 (44.0)

7 (38.9)

 

Smoked previously

   

0.419

 No

42 (97.7)

25 (100)

17 (94.4)

 

 Yes

1 (2.3)

0 (0)

1 (5.6)

 

Partner smokes

   

1

 No

38 (88.4)

22 (88.0)

16 (88.9)

 

 Yes

5 (11.6)

3 (12.0)

2 (11.1)

 

Marital status

   

0.419

 Married

42 (97.7)

25 (100)

17 (94.4)

 

 Not married

1 (2.3)

0 (0)

1 (5.6)

 

Place of birth

   

0.766

 Hong Kong SAR

33 (76.7)

19 (76.0)

14 (77.8)

 

 Mainland, China

6 (14.0)

3 (12.0)

3 (16.7)

 

 Others

4 (9.3)

3 (12.0)

1 (5.6)

 

Years living in HK (customized)

   

0.455

 <15 years

9 (20.9)

4 (16.0)

5 (27.8)

 

 > = 15 years

34 (79.1)

21 (84.0)

13 (72.2)

 

Educational level (customized)

   

0.47

 Postgraduate degree or above

14 (32.6)

9 (36.0)

5 (27.8)

 

 Below university level

8 (18.6)

3 (12.0)

5 (27.8)

 

 University degree

21 (48.8)

13 (52.0)

8 (44.4)

 

Family income per month (customized)

   

0.144

 HK$40,000 or more

38 (88.4)

24 (96.0)

14 (77.8)

 

 Under HK$40,000

5 (11.6)

1 (4.0)

4 (22.2)

 
  1. Categorical data are presented as number (percentage) and continuous variables as median (interquartile range). Within-group valid percentages are shown. Only subjects with both available antibody and 16 S data (at one week after second dose) were summarized in the table. P values were given by Fisher’s exact test for the categorical variables and Wilcoxon rank-sum test for continuous variables.
Back to article page