Table 2.

Descriptions of fetal growth phenotypes identified by univariate and multivariate latent class trajectory models in the LIFECODES Fetal Growth Study.

Univariate trajectory groups
Group	Name	Description
1	Extremely Small	Has modest consistent increase in growth rate, but overall, the smallest relative EFW from mid- to late pregnancy.
2	Small	Exhibits an increase in relative EFW during mid-pregnancy. Growth rate stabilizes in late pregnancy and relative size remains small (e.g., close to 10th percentile).
3	Average-Declining	EFW within normal range throughout, but growth rate declines after approximately 30 weeks gestation.
Multivariate trajectory groups
Group	Name	Description
1	Extremely Small	Smallest relative size of HC, AC, FL from mid- to late pregnancy with constant growth rate.
2	Small-Asymmetric HC:AC	Growth within normal range in mid-pregnancy. Relative HC normal through late pregnancy, but AC and FL growth rate slows across pregnancy.
3	Small-Symmetric HC:AC	All growth parameters within small or normal range from mid- to late-pregnancy. Stable growth rate from mid- to late pregnancy.
4	Average-Declining	Normal HC, AC, and FL size throughout, but growth rate slows across pregnancy for all measures of growth.