Table 1 Descriptive statistics of variables used in the analysis, n = person-years

Musculoskeletal disorders (n (%))

50,283 (3.2%)

329 (5.2%)

736 (5.2%)

Depression (n (%))

23,672 (1.5%)

139 (2.2%)

339 (2.4%)

Anxiety (n (%))

21,234 (1.3%)

119 (1.9%)

280 (2.0%)

Migraine (n (%))

7,561 (0.5%)

52 (0.8%)

123 (0.9%)

Sleeping disorder (n (%))

3,161 (0.2%)

34 (0.5%)

60 (0.4%)

Have had diagnosis prior to birth

None (n (%))

1,428,802 (91%)

5,573 (88%)

12,866 (90%)

Yes, at least one (n (%))

145,526 (9.2%)

770 (12%)

1,363 (9.6%)

Year of education, mother, mean (SD)

16.0 (4.08)

15.3 (4.29)

15.4 (4.19)

Household income quintile

Lowest (n (%))

293,595 (19%)

1,154 (18%)

2,36 (17%)

Second (n (%))

266,492 (17%)

1,289 (20%)

2,617 (18%)

Third (n (%))

292,679 (19%)

1,364 (22%)

2,879 (20%)

Fourth (n (%))

318,568 (20%)

1,343 (21%)

3,306 (23%)

Highest (n (%))

310,451 (20%)

1,147 (18%)

2,930 (21%)

Number of children

Single child (n (%))

297,200 (19%)

1,144 (18%)

3,182 (22%)

Two children (n (%))

831,425 (53%)

3,192 (50%)

6,699 (47%)

Three or more children (n (%))

445,703 (28%)

2,007 (32%)

4,348 (31%)

Employment status

Unemployed (n (%))

297,664 (19%)

1,474 (23%)

3,751 (26%)

Employed (n (%))

1,017,859 (65%)

4,071 (64%)

8,590 (60%)

Marital status

Married/partner (n (%))

1,411,309 (90%)

6,004 (95%)

13,111 (92%)

Divorced/Separated (n (%))

56,223 (3.6%)

300 (4.7%)

995 (7.0%)

Region of birth

Norway (n (%))

1,087,549 (69%)

4,639 (73%)

9,906 (70%)

Europe, North America, Australia (n (%))

210,763 (13%)

564 (8.9%)

1,354 (9.5%)

Africa, Asia, Latin America (n (%))

276,003 (18%)

1,140 (18%)

2,969 (21%)

Age at birth, mean (SD)

29.30 (5.16)

29.01 (5.44)

29.12 (5.60)

Child age, mean (SD)

3.78 (2.70)

4.67 (2.54)

5.90 (2.37)

Child sex

Boys (n (%))

807,617 (51%)

3,939 (62%)

9,162 (64%)

Girls (n (%))

766,711 (49%)

2,404 (38%)

5,067 (36%)