Maternal essential fatty acid patterns during normal pregnancy and their relationship to the neonatal essential fatty acid status

Abstract

Although essential fatty acids (EFA) and their longer chain, more unsaturated derivatives play a major role during pregnancy, hardly any information is available with respect to the course of the maternal EFA status during an uncomplicated pregnancy and its relationship to the neonatal EFA status.Therefore, a longitudinal study was started in which 110 pregnant women gave repeated blood samples from the loth week of gestation until delivery. After birth a blood sample from the umbilical vein and a maternal venous blood sample were collected as well, and 6 months after delivery a final blood sample from the mother was taken. The absolute (mg/l) and relative (% total fatty acids) amounts of the fatty acids in plasma phospholipids were determined. The total amounts of fatty acids increased significantly during pregnancy. This pattern was similar for the individual fatty acids and fatty acid families. The relative amount of linoleic acid (18:2n-6) did not change during pregnancy, whereas the relative amount of arachidonic acid (20 : 4n-6) decreased. Despite maternal mobilization of docosahexaenoic acid (22 : 6n-3, DHA), suggested by a temporary increase in the DHA status until 18 weeks gestation, the DHA status steadily declined thereafter. This pattern was associated with a progressive increase in the DHA deficiency index in maternal blood throughout pregnancy and resulted in a sub-optimal neonatal DHA status. The overall maternal EFA status also declined steadily during pregnancy. Therefore, the question arises whether the mother, under the prevailing dietary conditions, is able to meet the high fetal requirement for EFA.

Relation between birth order and the maternal and neonatal docosahexaenoic acid status

“…This seems likely, because at that period and particularly during the third trimester of gestation, fetal DHA requirement is especially high (Clandinen et al, 1980;Martinez, 1992;Innis, 1991;Houwelingen et al, 1996) In a recently performed study among 176 healthy Dutch gravidae, no signi®cant differences in nutrient intake during the course of pregnancy were observed between PG and MG (Al et al, 1995b), and therefore, the different DHA amounts in maternal plasma between PG and MG seems not to be due to a different fatty acid intake. Because the normal intake of DHA is rather low (estimated at 200 mg/ d) and the desaturation and elongation from its precursors occurs at a very slow rate only (Voss et al, 1992), it seems that the increase in the absolute DHA amounts during pregnancy (Al et al, 1995a) are the result of an increased mobilization of DHA from maternal body stores, although a metabolic re-routing cannot be excluded. It remains to be investigated whether these stores are more used up by women who have been pregnant more than once than by women who are pregnant for the ®rst time.…”

“…The study population consisted of pregnant women who took part in a longitudinal study to investigate the essential fatty acid status of women and their infants during pregnancy (Al et al, 1995a;Al et al, 1995b). To increase the number of women with higher gravida number ( !…”

“…The fatty acid compositions of phospholipids (PLs) isolated from maternal and umbilical plasma and umbilical artery and vein vessel walls were determined as described earlier (Al et al, 1995a;Foreman-van Drongelen et al, 1995). At the start of the analysis, approximately 40 mg of 1,2-dinonadecanoyl phosphatidyl choline 2 ] was added to the plasma sample as an internal standard to quantify the absolute fatty acid amounts, and 20 mg of 10-heptadecenoic acid (C17:1) was added to check carry over of free fatty acids during the PL separation procedure.…”

“…For each sample moment the following statistical tests were performed: (i) differences between primigravidae and multigravidae in DHA content, DHA de®ciency index and DHA suf®ciency index values of maternal and umbilical plasma PLs, and of umbilical tissue PL were studied using the two-tailed Student's ttest; (ii) pearson correlation coef®cients were calculated to study the relationship between gravida number on the one hand and the DHA content, the DHA de®ciency index and DHA suf®ciency index values of maternal plasma PLs, umbilical plasma PLs, and umbilical tissue PLs on the other hand. Since the neonatal DHA status is positively associated with gestational age at birth (Al et al, 1995a), multiple regression was performed on the umbilical fatty acid data to correct for differences in gestational age at birth.…”

“…Fatty acid synthesis in human placenta and fetal tissue is probably rather low (see for review : Innis, 1991) and, therefore, most of the fetal DHA has to be derived from the mother by placental transfer. Fatty acid analysis of maternal blood samples, taken regularly throughout normal pregnancy, revealed that the DHA amounts (mg/L) in plasma phospholipids (PL) increase by approximately 50% during the course of pregnancy (Al et al, 1995a). However, the ratio between 22:6n-3 and its`de®ciency' marker 22:5n-6 in maternal plasma PL decreased signi®-cantly during pregnancy.…”