5 kg) vs. normal birth weight (as a binary variable), small AZD6244 for gestational age vs. appropriate for gestational age (as a binary variable), rate of infant growth from birth to three months of age, infant weight at 12 months of age and season of birth (harvest/wet season January–June; hungry/dry season July–December). Rate of change in weight from birth to three months was calculated as the difference between sex-specific birth weight standard deviation score and sex-specific weight at three months standard deviation score. We also looked at weight for age standard

deviation differences between three and six months of age and six and 12 months of age. Associations between these early-life exposures and antibody responses were tested by multiple linear regression analysis. Probability values <0.05 were considered to be statistically significant for all tests. All statistical

analyses were performed using DataDesk, version 6 for Windows, Data Description Inc., Ithaca, NY. A total of 858 individuals met the criteria for recruitment into the current study. Of these, 78 were known to have died prior to follow up, leaving a cohort of 781 to be traced. Of this number, 145 were excluded on the basis they were currently participating in another ongoing study and three because they were confirmed to be pregnant by an MRC midwife prior to the start of the study. Of the remaining 633 individuals who were eligible to participate, 241 were not available [dead (4), self-confirmed as pregnant (45), RGFP966 overseas (24), outside designated study area (58), not traceable (50), traceable but unavailable for study (60)] and 72 did not consent to participate. A total of 320 subjects Megestrol Acetate (41% of 781 followed up) consented and participated in the current study. Compared to non-participants, participants were younger (22.2 y vs. 23.0 y; p < 0.0001) and there were significantly more males than females (51.9% vs. 45.3%). No differences were observed between the participants and

non-participants in available early-life information (data not presented). Table 1 details the early-life characteristics of the subjects recruited. A total of 41 (12.8%) of subjects were born of a low birth weight (<2.5 kg), and a higher proportion of these were female. Of these, 13 were born pre-term (<37 weeks gestation), although 9 had a missing gestational age. A total of 267 (83%) of the cohort had gestational age assessments available. Using the William’s reference data [15], 51 (19%) of these infants would be considered small for gestational age (SGA). Male subjects were significantly heavier at three months and at 12 months of age, but the rate of early growth, expressed as the sex-specific change in z-score between birth and three months of age, three to six months, or six to twelve months did not differ between males and females. Characteristics of the study participants at follow up are detailed in Table 2.