Table 1.

Characteristics of children aged 12–23 months at the time of receipt of first dose of measles-containing vaccine by gestational age.

	Gestational age category (weeks)
	Preterm (<37)	Full-term (≤37)
Number of children	45,343	487,032
Vaccine received, n (%)
MMR	37,262 (82.2)	403,238 (82.8)
MMRV	8081 (17.8)	83,794 (17.2)
Sex, n (%)
Female	20,779 (45.8)	239,775 (49.2)
Male	24,564 (54.2)	247,257 (50.8)
Age at vaccination in months, mean (SD)	13.30 (1.98)	13.33 (2.01)
Calendar month of vaccination, n (%)
November through April	22,197 (49.0)	234,430 (48.1)
May through October	23,146 (51.0)	252,602 (51.9)
Birth weight in grams, mean (SD)	2417 (6 4 9)	3449 (4 7 4)
Maternal age in years, mean (SD)	31.9 (5.7)	31.1 (5.3)

Abbreviations: MMR, measles-mumps-rubella; MMRV, measles-mumps-rubella-varicella; SD, standard deviation.