In their review of birth records of 913,320 singleton births in New York City from 1995 to 2003, Stein (information contributed to the committee in consultation with Stein [see Appendix G, Part III]) found that Asian and non-Hispanic black women were more likely to gain 0 to 9 kg, whereas Hispanic and non-Hispanic white women were more likely to gain 20+ kg during pregnancy. Table 4-2 presents GWG among women of different race and ethnicity in this study population.

Taken together, the limited data on the influence of race/ethnicity on GWG is suggestive of inadequate GWG among some racial/ethnic groups. However, the paucity of data on a national level and the lack of observational studies based on prepregnancy BMI preclude drawing any conclusions about the influence of race/ethnicity on GWG (see Chapter 2 and Figure 2-6 for trends in GWG for racial/ethnic groups by prepregnancy BMI).

The committee also found few studies that have reported GWG by socioeconomic status (SES), and even fewer that considered the influence of the many possible determinants of GWG among different SES groups; or alternatively, adjusted for SES in their analyses (see Appendix D). Using 2004-2005 PRAMS data, Chu et al. (2009) found that women with less than 12 years of education were more likely to gain less than 15 pounds, and less likely to gain more than 34 pounds, compared to women with more than 12 years of education (Table 4-3).