The longitudinal relationship between PA and lipids in
pregnancy has not been studied very well previously. We
found more time spent in MVPA to be related to lower
triglyceride levels at 32 weeks of pregnancy, but not with
other lipids. In late pregnancy, lipids are used as a maternal
energy source, thus sparing glucose and amino acids for
the fetus (26). Furthermore, triglycerides are also a source
of fatty acids for the fetus and are important for fetal
growth (27). Other studies also reported that higher levels
of PA were associated with lower triglycerides (28, 29).
The effect of PA on triglycerides might (partly) be mediated
through changes in insulin sensitivity (30, 31).
Whether the PA-related reduction in triglycerides will impact
fetal growth has not been studied so far, and from the
scarcity of data, it is clear that the role of PA on lipid
profiles during pregnancy needs further study.