Table 2.

Adjusted mean differences and relative risks for offspring weight outcomes through childhood and adolescence by categories of average number of night shifts worked per month during pregnancy using data from GUTS2 from 2004 to 2013 restricted to singleton, full‐term births (n = 545)

Average number of night shifts/ month
	None	<3 nights/month		3‐9 nights/month		≥10 nights/month		P trend	Any number nights/month
MD in offspring birth weight (g)
Participants	352	39		17		35			91
		MD	95% CI	MD	95% CI	MD	95% CI		MD	95% CI
Basic modela	0 (reference)	−54.19	−209.96 to 101.58	−203.53	−432.97 to 25.92	−46.27	−210.25 to 117.70	0.23	−79.04	−187.53 to 29.45
MV model 1b	0 (reference)	−54.48	−215.12 to 106.17	−231.85	−463.36 to −0.33	18.94	−146.85 to 184.73	0.58	−57.76	−170.10 to 54.58
MV model 2c	0 (reference)	−64.28	−225.75 to 97.19	−223.23	−456.26 to 9.80	19.51	−146.50 to 185.51	0.60	−59.64	−172.11 to 52.82
RR of offspring's somatotype at age 5 being larger than the median
Cases/participants	159/417	16/43		8/21		10/45			34/109
		RR	95% CI	RR	95% CI	RR	95% CI		RR	95% CI
Basic modela	1 (reference)	0.95	0.64 to 1.42	1.01	0.57 to 1.78	0.59	0.34 to 1.04	0.08	0.82	0.60 to 1.11
MV model 1b	1 (reference)	0.96	0.62 to 1.47	1.03	0.60 to 1.78	0.59	0.33 to 1.04	0.09	0.82	0.60 to 1.12
MV model 2c	1 (reference)	0.96	0.63 to 1.48	1.06	0.61 to 1.84	0.59	0.33 to 1.05	0.10	0.82	0.60 to 1.13
RR of offspring having overweight or obesity at any time between 2004 and 2013 d
Cases/participants	156/431	12/43		4/21		13/45			29/109
		RR	95% CI	RR	95% CI	RR	95% CI		RR	95% CI
Basic modela	1 (reference)	0.75	0.46 to 1.21	0.54	0.22 to 1.33	0.82	0.51 to 1.31	0.19	0.74	0.53 to 1.03
MV model 1b	1 (reference)	0.76	0.45 to 1.29	0.51	0.20 to 1.27	0.80	0.49 to 1.29	0.16	0.73	0.51 to 1.03
MV model 2c	1 (reference)	0.80	0.48 to 1.35	0.53	0.21 to 1.37	0.78	0.48 to 1.25	0.14	0.74	0.52 to 1.05
MD in offspring BMI (kg/m2) using n = 1,632 repeated measurements, 2004‐2013
Observations	1,306	120		64		142			326
		MD	95% CI	MD	95% CI	MD	95% CI		MD	95% CI
Basic modela,e	0 (reference)	0.24	−0.85 to 1.32	−0.27	−1.78 to 1.23	−0.02	−1.07 to 1.03	0.88	0.03	−0.69 to 0.75
MV model 1b	0 (reference)	0.21	−0.91 to 1.34	−0.54	−2.08 to 1.00	−0.21	−1.29 to 0.87	0.56	−0.11	−0.86 to 0.64
MV model 2c	0 (reference)	0.45	−0.64 to 1.54	−0.26	−1.75 to 1.24	−0.31	−1.35 to 0.73	0.53	−0.01	−0.74 to 0.72

Abbreviations: CI, confidence interval; MD, mean difference; MV, multivariable model; RR, relative risk.

^aAdjusted for offspring gender (boy/girl) and gestational age ≥ 42 weeks (yes/no).

^bAdditionally adjusted for maternal age at pregnancy, smoking status before pregnancy (never, current, past), alternative healthy eating score (quintiles), physical activity (MET‐hours /week; quintiles), husband's education (less than 2 years of college, 4 years of college, graduate school), parity (nulliparity, 1, 2, or 3+ previous pregnancies), history of rotating night shift work (never, <3 years, 3‐5 years, ≥6 years).

^cAdditionally adjusted for BMI before pregnancy (<25, 25‐29, ≥30 kg/m²).

^dOverweight and obesity status defined according to age‐ and sex‐specific cutoffs from International Obesity Task Force.

All models are additionally adjusted for age at BMI measurement.