Changes in plasma non esterified fatty acids and serum glycerol in pregnancy.

Changes in plasma nonesterified fatty acids (NEFA) and serum glycerol in pregnancy were examined in a semi-serial study of 85 women. A preliminary study showed that it was almost impossible to achieve standardized conditions for sampling, and the compromise of taking a single venous sample without stasis, after 30 minutes rest and about 12 hours fasting, was adopted. Although there were large individual variations the patterns of change were, in general, the same for NEFA and glycereo although the two were not closely correlated. There was no +convincing change before 30 weeks of pregnancy but both increased in the last ten weeks, fell sharply in the first week post partum, and then rose again to late pregnancy levels by 6 weeks post partum before falling to non-pregnant levels by between 3 and 6 months post partum. Those patterns of change are in broad accordin with changes of fat storage and lipolysis associated with the reporoductive cycle. Changes in the patterms of NEFA were triviax the only significant alteration was a small rise in the proportion of C16:0 (palmitic) in late pregnancy.     

Longitudinal study of platelet indices during normal pregnancy

The purpose of this longitudinal, prospective study was to define platelet indices during normal pregnancy and to compare them to normal nonpregnant values. Indices evaluated included platelet count, mean platelet volume, and platelet distribution width. No significant change occurred in the mean platelet count or mean platelet volume from the second to the third trimester; however, platelet distribution width increased progressively and significantly during this interval (p less than 0.0001). Mean platelet volume versus platelet count showed a significant inverse relationship (p less than 0.0001) and was congruent with normal nonpregnant values. Mean platelet volume versus platelet distribution width exhibited a significant direct relationship (p less than 0.03) that differed remarkably from normal nonpregnant values. These data support the concept of normal pregnancy as a compensated state of progressive platelet consumption. These findings may have important diagnostic and prognostic applications in discerning acute states of platelet consumption superimposed on the compensated consumption of normal pregnancy.     

Longitudinal study of plasma lipids and lipoprotein cholesterol in normal pregnancy and puerperium

Plasma lipids and lipoprotein cholesterol distribution were measured in 60 normal pregnancies studied longitudinally at 12, 20, 28, and 36 weeks of gestation and 3 and 40 days postpartum. Total cholesterol, unesterified cholesterol, phospholipids, triglycerides and cholesterol in low- and very-low-density lipoproteins rose progressively during pregnancy. Maximal values were reached at 36 weeks for total cholesterol, unesterified cholesterol and low-density lipoprotein cholesterol and at partum for triglycerides, very-low-density lipoprotein cholesterol and phospholipids. High-density lipoprotein cholesterol was hardly affected by pregnancy. During the second half of pregnancy and postpartum period, high-density lipoprotein cholesterol was consistently and negatively correlated with triglycerides and very-low-density lipoprotein cholesterol. In each period studied total cholesterol showed very high positive correlation with low-density lipoprotein cholesterol but a weak correlation with high-density lipoprotein cholesterol.     

Depressive symptoms during pregnancy and the concentration of fatty acids in breast milk

The aim of the present study was to examine the association between depressive symptoms in pregnancy and the concentration of long-chain polyunsaturated fatty acids (LCPUFAs) in breast milk. Women (n = 287) enrolled in the Pregnancy, Infection, and Nutrition Study completed the Center for Epidemiologic Studies Depression Scale in pregnancy (< 20 and 24-29 weeks) and had LCPUFAs measured in breast milk (4 months postpartum). Multiple linear regression was used to examine associations between depressive symptoms and breast milk LCPUFAs. Increasing depressive symptoms at < 20 weeks were associated with lower docosahexaenoic acid concentrations (adjusted β = -1.15, 95% confidence interval = -2.12, -0.19). No similar associations were observed with other fatty acids nor between symptoms at 24-29 weeks and LCPUFAs. Depressive symptoms, even in the subclinical range, early in pregnancy are inversely associated with breast milk docosahexaenoic acid. This may have implications for the timing of screening and interventions for perinatal depression and the nutritional value of breast milk.     

Changes in erythrocyte and plasma zinc concentrations in pregnancy

In a group of normal pregnant women, erythrocyte and plasma zinc concentrations were assessed at 8, 15, 25 and 35 weeks. Erythrocyte zinc concentration showed an increasing trend with a peak value at 25 weeks, although the increase did not reach a significant level. Plasma zinc concentration showed a significant decrease with the lowest value at 35 weeks. Erythrocyte and plasma zinc concentrations were not correlated, and there was no correlation between either of these concentrations and human chorionic gonadotrophin at 8-15 weeks. The value of zinc measurements in the management of complicated pregnancies is discussed.     

Supplementation of n-3 fatty acids during pregnancy and lactation reduces maternal plasma lipid levels and provides DHA to the infants

Objective.?Docosahexaenoic acid (DHA, 22:6 n-3) is considered an essential fatty acid for the fetus and newborn infant, but the optimal level of supply is not known. We studied the effect of supplementing pregnant and lactating women with marine n-3 polyunsaturated fatty acids (PUFAs) as compared to n-6 PUFAs related to maternal and infant lipid levels.

Study design.?Five hundred and ninety pregnant women in weeks 17–19 of pregnancy were recruited. They were given either 10 mL cod liver oil (n-3 PUFAs) or corn oil (n-6 PUFAs) daily until three months after delivery, and 341 women took part in the study until giving birth.

Results.?Maternal supplementation with cod liver oil increased the concentration of DHA in maternal as well as infant plasma and umbilical tissue phospholipids, as compared to corn oil. The maternal plasma triacylglycerol increase during pregnancy was less pronounced in women supplemented with cod liver oil as compared to corn oil. The concentration of high-density lipoprotein (HDL)-cholesterol was unchanged during pregnancy in the cod liver oil group, whereas it decreased in the corn oil group, promoting a greater increase in the ratio of total cholesterol/HDL-cholesterol in the corn oil group.

Conclusion.?Maternal supplementation with n-3 fatty acids during pregnancy and lactation provides more DHA to the infant and reduces maternal plasma lipid levels compared to supplementation with n-6 fatty acids.     

Supplementation of n-3 fatty acids during pregnancy and lactation reduces maternal plasma lipid levels and provides DHA to the infants.

OBJECTIVE: Docosahexaenoic acid (DHA, 22:6 n-3) is considered an essential fatty acid for the fetus and newborn infant, but the optimal level of supply is not known. We studied the effect of supplementing pregnant and lactating women with marine n-3 polyunsaturated fatty acids (PUFAs) as compared to n-6 PUFAs related to maternal and infant lipid levels. STUDY DESIGN: Five hundred and ninety pregnant women in weeks 17-19 of pregnancy were recruited. They were given either 10 mL cod liver oil (n-3 PUFAs) or corn oil (n-6 PUFAs) daily until three months after delivery, and 341 women took part in the study until giving birth. RESULTS: Maternal supplementation with cod liver oil increased the concentration of DHA in maternal as well as infant plasma and umbilical tissue phospholipids, as compared to corn oil. The maternal plasma triacylglycerol increase during pregnancy was less pronounced in women supplemented with cod liver oil as compared to corn oil. The concentration of high-density lipoprotein (HDL)-cholesterol was unchanged during pregnancy in the cod liver oil group, whereas it decreased in the corn oil group, promoting a greater increase in the ratio of total cholesterol/HDL-cholesterol in the corn oil group. CONCLUSION: Maternal supplementation with n-3 fatty acids during pregnancy and lactation provides more DHA to the infant and reduces maternal plasma lipid levels compared to supplementation with n-6 fatty acids.     

Longitudinal study of serum thyroid hormone levels during normal pregnancy.

We undertook a prospective longitudinal study of thyroid function in 60 normal pregnant women and measured serum concentrations of T4, triiodothyronine (T3), T-uptake, thyroxine binding globulin (TBG), free thyroxine index (FTI), free T4, albumin and thyrotropin (TSH). From these data we established reference ranges for each of these analytes for each trimester and examined the inter-relationships between laboratory measurements of thyroid function tests. We observed significant increases in serum concentrations of thyrotropin and decreases in free T4, assays commonly used as first line investigations of thyroid activity during pregnancy. However, the 95th centile intervals for both analytes remained within the reference range for nonpregnant women.     

孕晚期脂肪细胞膜脂肪酸组成与胰岛素抵抗的关系

目的 :探讨孕晚期脂肪细胞膜脂肪酸组成与胰岛素抵抗的关系。方法 :正常妊娠 40例 ,妊娠期糖尿病 (GDM)孕妇 41例 ,以胰岛素敏感指数 (ISI)评价胰岛素抵抗程度 ;在剖宫产时随机抽取正常妊娠和GDM孕妇各 1 0例 ,取皮下脂肪各 1 0g,用气相色谱法测定脂肪细胞膜脂肪酸。结果 :GDM孕妇ISI为 4 .2 5± 0 .51 ,明显高于正常孕妇的 3.52±0 .56,(P <0 .0 0 1 )。GDM脂肪细胞膜饱和脂肪酸 (SFA)百分含量为 30 .42±1 .1 6,高于正常妊娠的 2 6 .92±3 .63(P <0 .0 5) ;多不饱和脂肪酸 (PUFA)百分含量为 2 5 .94± 2 .82 ,明显低于正常妊娠的 30 .2 7± 3.2 1 (P <0 .0 1 ) ,单不饱和脂肪酸 (MUFA)百分含量为 43.64± 3 .31 ,正常妊娠为 42 .81± 1 .80 ,差异无显著性 (P >0 .0 5)。对ISI与脂肪细胞膜脂肪酸饱和程度偏相关分析 ,ISI与脂肪细胞膜SFA含量呈正相关 (r=0 .5541 ,P <0 .0 5) ;与脂肪细胞膜PUFA含量呈负相关 (r=- 0 .52 93 ,P <0 .0 5) ;与脂肪细胞膜MUFA无相关。结论 :GDM的胰岛素抵抗可能与脂肪细胞膜多不饱和脂肪酸减少有关     

Free amino acids in plasma throughout pregnancy

Plasma amino acid analyses on 27 amino acids in serial samples from 15 pregnancies in 14 patients are reported. Variations of amino acid levels with gestational age are reported both for absolute amino acid levels and for levels normalized to total amino acids, with a t test used to determine which amino acids vary significantly. The extent to which individual results differ from the means is indicated. Correlation and regression analyses were done for each amino acid vs. every other amino acid and for each amino acid vs. gestational age. Significant differences were found in amino acid results for plasma from an individual in whom pregnancy resulted in spontaneous abortion.     

L-arginine erythrocyte transport increases during pregnancy and immediately postpartum

OBJECTIVE: This study was undertaken to evaluate erythrocyte membrane transport of L-arginine in pregnancy and immediately postpartum. STUDY DESIGN: The study comprised 103 women with normal pregnancy, initially evaluated at the second trimester (II), followed into the third trimester (III), and immediately postpartum (PP). Total erythrocyte L-arginine uptake was measured with (14)C-L-arginine, at 37 degrees C, for 3 minutes. The maximal transport capacity (V(max)) and half-saturation constant (K(m)) were obtained with the use of Michaelis-Menten kinetics. Results are expressed as mean+/-SD. Analysis of variance, followed by Tukey test, was used in statistical analysis (alpha< or =.05). RESULTS: V(max) (micromol/L cells per hour) progressively increased at each consecutive time period: 779+/-283, 946+/-289, and 1349+/-390, at II, III, and PP, respectively (P<.001). Similarly, K(m) (micromol/L) values increased from 56+/-20 at time II, to 62+/-18 at time III, and 69+/-24 at PP (P<.001). CONCLUSION: Total erythrocyte L-arginine uptake (V(max) and K(m)) increases progressively along normal pregnancy, with a further increase immediately postpartum.     

Relationship between high consumption of marine fatty acids in early pregnancy and hypertensive disorders in pregnancy

OBJECTIVE: To investigate whether there is a relationship between maternal intake of cod-liver oil in early and late pregnancy and hypertensive disorders in pregnancy. DESIGN: An observational prospective study. SETTING: Free-living conditions in a community with traditional fish and cod-liver oil consumption. POPULATION: Four hundred and eighty-eight low-risk pregnant Icelandic women. METHODS: Maternal use of cod-liver oil, foods and other supplements was estimated with a semiquantitative food frequency questionnaire covering food intake together with lifestyle factors for the previous 3 months. Questionnaires were filled out twice, between 11 and 15 weeks of gestation and between 34 and 37 weeks of gestation. Supplements related to hypertensive disorders in pregnancy, i.e. gestational hypertension and pre-eclampsia, were presented, with logistic regression controlling for potential confounding. MAIN OUTCOME MEASURES: Gestational hypertension, pre-eclampsia, cod-liver oil and multivitamins. RESULTS: The odds ratio for developing hypertensive disorders in pregnancy for women consuming liquid cod-liver oil was 4.7 (95% CI 1.8-12.6, P= 0.002), after adjusting for confounding factors. By dividing the amount of n-3 long-chain polyunsaturated fatty acids (n-3 LCPUFA) into centiles, the odds ratio for hypertensive disorders across groups for n-3 LCPUFA suggested a u-shaped curve (P = 0.008). Similar results were found for gestational hypertension alone. Further, the use of multivitamin supplements without vitamins A and D in late pregnancy doubled the odds of hypertensive disorders (OR 2.4, 95% CI 1.0-5.4, P= 0.044). CONCLUSIONS: Consumption of high doses of n-3 LCPUFA in early pregnancy, or other nutrients found in liquid cod-liver oil, may increase the risk of developing hypertensive disorders in pregnancy.     

Plasma lipids and physicochemical properties of the erythrocyte plasma membrane throughout pregnancy

BACKGROUND: The physiopathological relevance of plasma lipid concentrations is supported by the observation that they might affect the physicochemical properties of the plasma membrane of circulating cells and might be crucial in the pathological conditions complicating pregnancy. METHODS: Plasma and erythrocyte membrane lipid composition, membrane fluidity and function [membrane-bound enzyme sodium/potassium adenosine triphosphatase (Na+/K+-ATPase) activity] were studied in 24 healthy women in the nonpregnant condition and at 12, 24 and 38 weeks' gestation. RESULTS: The plasma showed an increase in total and high density lipoprotein (HDL) cholesterol, triglyceride (TG) and phospholipid (PL) levels. In the erythrocyte membrane we found the cholesterol/phospholipid (C/PL) ratio increased and the saturated to unsaturated fatty acid (FA) ratio (Sat/Unsat) significantly reduced; fluorescence polarization showed an initial increase during pregnancy and a progressive decrease afterwards; Na+/K+-ATPase activity was progressively reduced. CONCLUSIONS: A generalized alteration in the composition and function of the maternal erythrocyte membrane is present during a physiological pregnancy, and these modifications may involve a more complex physiopathogenetic mechanism.