Background: Pregnancy is associated with increases in fasting
triglycerides and total cholesterol. ApoE isoforms are known to
influence the concentration of cholesterol, with apoE2 homozygosity
lowering and apoE4 homozygosity raising the cholesterol concentration
compared with E3 homozygosity. The lipid profiles ApoE status and
prevalence of small dense LDL species were evaluated for subjects
attending an antenatal clinic. Results: Samples from 690 women aged
between 16 and 42 years of age were analyzed during and after
pregnancy. The fasting plasma triglyceride concentration (in mmol/L)
was significantly higher in pregnancy (median = 1.5, IQR 1.0-2.0 vs
median = 0.6, IQR 0.5-0.8 respectively, p < 0.0001). Similarly, the
total cholesterol (in mmol/L) was increased during pregnancy
(median=4.1, IQR 3.6-4.7 vs median 3.5, IQR 3.1-3.5, respectively
p=0.0167). The median LDL cholesterol and HDL cholesterol did not
change. Higher proportions of small density LDL species were seen
during pregnancy compared to after pregnancy. The distribution of the
LDL species during pregnancy and 6 weeks post-partum were significantly
different p<0.0001 with the smaller species being much higher during
pregnancy. Conclusion: ApoE4 genotype was associated with increased
total cholesterol and LDL cholesterol concentrations during pregnancy.
Pregnancy results in a reversible remodeling of LDL to smaller species,
the significance of which is unknown but may indicate a predisposition
to atherosclerosi