Table 2 Birth weight linear regression GAM (model 1.1)

Heatwave (ref: 0)

1

9.02

6.02

12.02

0.01

<0.0001

Great Recession (continuous)

-9.63

-18.25

-1.01

0.00

0.03

COVID (continuous)

11.67

5.47

17.88

0.00

<0.001

Time (by month)

0.04

0.01

0.06

0.00

<0.01

SSEP (/10 points)

4.55

3.43

5.68

0.01

<0.0001

Altitude (/100m)

-6.99

-7.50

-6.48

0.02

<0.0001

Parity (ref: 1)

2

123.41

121.46

125.36

0.11

<0.0001

3

163.35

160.37

166.33

0.10

<0.0001

>3

188.44

183.28

193.60

0.06

<0.0001

Sex (ref: male)

Female

-132.26

-133.99

-130.52

0.13

<0.0001

Urban (ref: rural)

Urban

2.07

0.25

3.89

0.00

0.03

Language region (ref: German)

French

-52.98

-55.09

-50.87

0.04

<0.0001

Italian

-89.20

-94.06

-84.33

0.03

<0.0001

Maternal nationality (ref: Swiss)

Africa

11.90

6.65

17.15

0.00

<0.0001

Asia

-58.83

-63.60

-54.06

0.02

<0.0001

Europe

27.09

25.11

29.07

0.02

<0.0001

Northern America

71.72

60.35

83.09

0.01

<0.0001

Southern/Central America

5.58

-0.99

12.16

0.00

0.10

Civil status (ref: married)

Single

-37.88

-40.03

-35.73

0.03

<0.0001

Smooth variables

Maternal age (years)

<0.0001

Seasonality (month)

<0.01

n=1’263’853