Objective To determine the composition of esterified and free fatty acids in sera of women with normal and pre-eclamptic pregnancy.
Setting Department of Obstetrics and Gynaecology, Aker Hospital, Oslo, Norway.
Subjects Blood samples were taken from 510 healthy nulliparae at a gestational age of 17–19 weeks. Nineteen of these subsequently developed pre-eclampsia. Seventeen of these, for whom blood samples were still available, and a control group of 17 women taken from the same population and matched for age, body mass index, gestational age and parity, were later studied in detail. A further group of 29 women admitted to the hospital with pre-eclampsia were also studied, as was a matched control group of 29 women with normal pregnancies recruited from the antenatal clinic.
Methods Blood samples were drawn after 8 to 10 h fasting. The patterns of serum free fatty acids and esterified fatty acids were determined by thin-layer chromatography combined with gas-liquid chromatography. Free fatty acids were also determined enzymatically.
Results Among the circulating free fatty acids, the levels of palmitic (16:0), oleic (18:1 12–9) and linoleic acids (18:2 n-6) were significantly higher early in pregnancy in women who later developed pre-eclampsia. The same free fatty acids were also significantly increased in women with pre-eclampsia. The level and composition of the esterified fatty acids in phospholipids, triglycerides and cholesteryl esters did not, however, differ between the two groups early in pregnancy. In contrast, in women with pre-eclampsia, the relative content of oleic acid was increased in the phospholipid fraction, whereas linoleic acid was decreased in the phospholipid and triglyceride fractions.
Conclusions We observed that the level and composition of circulating free fatty acids were already altered 10–20 weeks before the clinical onset of pre-eclampsia. When the disease became overt there were changes in both esterified and free fatty acids.