Table 3

Gender effect on growth and sleep patterns; measurements at 9 months in preterm infants and 18 months in term infants adjusted for measurements at 12 weeks*

	Preterm infants							Term infants
	Males			Females			p	Males			Females			p
	n	Mean	SE	n	Mean	SE	p	n	Mean	SE	n	Mean	SE	p
*ANCOVA adjusting for measurement at 12 weeks, weaning behaviour (solids ⩽12 weeks v >12 weeks), milk feeding (breast v formula), gender, and (for term infants) whether AGA or SGA. Adjusted means are shown.
Weight gain (kg)	224	8.35	0.06	243	8.17	0.06	0.007	343	10.9	0.05	333	10.7	0.05	0.002
Length gain (cm)	222	71.0	0.19	242	70.0	0.19	<0.001	344	81.3	0.14	333	80.1	0.14	0.03
Head circumference gain (cm)	224	46.0	0.1	242	45.6	0.10	<0.001	345	48.3	0.06	335	48.0	0.06	0.001
Triceps skinfold gain (mm)	223	8.68	0.17	243	8.61	0.23	NS	341	8.8	0.12	335	8.9	0.13	NS
Subscapular skinfold gain (mm)	223	6.24	0.12	243	6.35	0.11	NS	341	6.2	0.07	334	6.3	0.08	NS
Sleep duration 9 mth (h)	210	11.1	0.14	225	11.2	0.13	NS	612	11.3	0.07	575	11.3	0.07	NS
Sleep duration 18 mth (h)	201	11.5	0.19	218	11.5	0.18	NS	582	11.5	0.7	540	11.6	0.07	NS