V21 Constitutional states in development 
V21.0 Period of rapid growth in childhood convert V21.0 to ICD-10-CM V21.1 Puberty convert V21.1 to ICD-10-CM V21.2 Other development of adolescence convert V21.2 to ICD-10-CM V21.3 Low birth weight status 
V21.30 Unspecified low birth weight status convert V21.30 to ICD-10-CM V21.31 Low birth weight status less than 500 grams convert V21.31 to ICD-10-CM V21.32 Low birth weight status 500-999 grams convert V21.32 to ICD-10-CM V21.33 Low birth weight status 1000-1499 grams convert V21.33 to ICD-10-CM V21.34 Low birth weight status 1500-1999 grams convert V21.34 to ICD-10-CM
V21.35 Low birth weight status 2000-2500 grams convert V21.35 to ICD-10-CM V21.8 Other specified constitutional states in development convert V21.8 to ICD-10-CM V21.9 Unspecified constitutional state in development convert V21.9 to ICD-10-CM