The Social Security Administration has revised its listing for children with growth disorders and weight loss. (Listing 100.00 and other sections) This rule was published at 80 Fed. Reg. 19522 (Apr. 13, 2015) and went into effect on June 12, 2015. Babies born at at 32 weeks of gestation and weight less than 1250 grams meet the listing. Babies who weight less than 1200 grams at birth meet a different part of the listing regardless of how many weeks of gestation they had.
There are some new listings regarding children's growth disorders. For example, section 100.5 pertains to children under 3 who "fail to thrive". There are also new listings for growth failure caused by chronic respiratory disorders (listing 103.06) and for renal disease (listing 106.08). However, some listings were eliminated: (listings 100.02 and 100.03) for growth impairments related to a medically determinable impairment.
The new listing's objective is not to rely anymore on "linear growth" (height) alone, but also on a child's weight to length ratio or body mass index.