Maternal lipid profile and the relation with spontaneous preterm delivery: a systematic review

Lipid metabolism during pregnancy: consequences for mother and child

PURPOSE OF REVIEW

Accommodating fetal growth and development, women undergo multiple physiological changes during pregnancy. In recent years, several studies contributed to the accumulating evidence about the impact of gestational hyperlipidemia on cardiovascular risk for mother and child. This review aims to provide a comprehensive overview of the current research on lipid profile alterations during pregnancy and its associated (cardiovascular) outcomes for mother and child from a clinical perspective.

RECENT FINDINGS

In a normal pregnancy, total and LDL-cholesterol levels increase by approximately 30-50%, HDL-cholesterol by 20-40%, and triglycerides by 50-100%. In some women, for example, with familial hypercholesterolemia (FH), a more atherogenic lipid profile is observed. Dyslipidemia during pregnancy is found to be associated with adverse (cardiovascular) outcomes for the mother (e.g. preeclampsia, gestational diabetes, metabolic syndrome, unfavorable lipid profile) and for the child (e.g. preterm birth, large for gestational age, preatherosclerotic lesions, unfavorable lipid profile).

SUMMARY

The lipid profile of women during pregnancy provides a unique window of opportunity into the potential future cardiovascular risk for mother and child. Better knowledge about adverse outcomes and specific risk groups could lead to better risk assessment and earlier cardiovascular prevention. Future research should investigate implementation of gestational screening possibilities.

The association between pregnancy levels of blood lipids and the risk of preterm birth

Preterm labor, a condition associated with various risk factors such as a history of prior preterm birth (PTB) and multiple pregnancies, has recently seen an increasing focus on its potential link with dyslipidemia. This study aims to investigate the relationship between dyslipidemia in expectant mothers and the risks of PTB. We studied 6963 mothers who gave birth at the International Peace Maternal and Child Health Hospital of Shanghai Jiaotong University School of Medicine in 2020, among which, 437 women had PTB. We extracted clinical and lipid data from electronic records, using multivariable logistic regression and restricted cubic spline models to explore the link between lipid concentrations (by quartiles) in pregnancy stages and PTB risk. The PTB rate was 6.3%. Early pregnancy in the PTB group showed elevated ApoA, ApoB, CHOL, LDL, and TG levels compared to controls (all P < 0.05). Late pregnancy showed no notable lipid differences. Multivariable analysis revealed elevated ApoA, TG, higher age, BMI ≥ 28 kg/m2, hypertension, assisted reproductive technology and gestational diabetes as PTB risk factors (all P < 0.05). After adjustments, higher ApoA, ApoB, CHOL and TG levels correlated with increased PTB risk. Using the lowest quartile, the adjusted ORs for early pregnancy's highest quartile of ApoA, ApoB, CHOL and TG were 1.348, 1.442, 1.442 and 2.156, respectively. Our findings indicate that dyslipemia in early pregnancy, including elevated levels of ApoA, ApoB, CHOL and TG, are associated with PTB. Managing lipid abnormalities during pregnancy may help reduce the risk of PTB.

The Associations of Maternal Blood Hemoglobin and Serum Triglyceride Levels and the Risk of Preterm Delivery

The abnormal hemoglobin (HGB) and serum lipid concentrations during pregnancy will increase the risk of preterm delivery. Our study aimed to explore the correlation between prenatal HGB and serum lipid levels and preterm delivery. We enrolled 215 mother-infant pairs in a pilot cohort study. The logistic regression model and Restricted Cubic Spline model (RCS) were used to investigate the levels of prenatal blood HGB and serum lipid such as triglyceride (TG), total cholesterol, high-density lipoprotein, low density lipoprotein and preterm delivery. The results showed that moderate levels of prenatal blood HGB (OR=0.28; 95%CI: 0.10, 0.75, p-trend=0.018) and high level of serum TG (OR=0.29; 95%CI: 0.10, 0.84, p-trend=0.022) level were negatively associated with the risk of preterm delivery. The joint effect results showed that compared with lower level of prenatal blood HGB (≤123.13 g/l) and TG (≤3.7 mmol/l), we found that high levels prenatal blood HGB and serum TG (OR=0.32, 95%CI: 0.12, 0.89) had a negative association with the risk of preterm delivery. Moreover, prenatal blood HGB and serum TG levels had negative linear dose-effect relationships with the risk of preterm delivery in overall and girl group (p<0.05). Moderate levels of prenatal blood HGB and high level of serum TG were negatively associated with the risk of preterm delivery. The joint effect of high levels prenatal HGB and prenatal serum TG in the normal range were negatively correlated with preterm delivery. Moreover, the underlying mechanisms should be clarified in future studies.

Prediction of adverse pregnancy outcomes by first-trimester components of metabolic syndrome: a prospective longitudinal study

PURPOSE

This study aimed to identify the optimal cutoff values of each component of metabolic syndrome (MetS) in the first trimester of pregnancy for predicting adverse pregnancy outcomes.

METHODS

A total of 1076 pregnant women in the first trimester of gestation were recruited in this prospective longitudinal cohort study. Specifically, 993 pregnant women at 11-13 weeks of gestation who were followed up until the end of pregnancy were included in the final analysis. The cutoff values of each component of MetS in the occurrence of adverse pregnancy outcomes including gestational diabetes (GDM), gestational hypertensive disorders, and preterm birth were obtained via receiver operating characteristic (ROC) curve analysis using the Youden's index.

RESULTS

Among the 993 pregnant women studied, the significant associations between the first trimester MetS components and adverse pregnancy outcomes were as follows: triglyceride (TG) and body mass index (BMI) with preterm birth; mean arterial pressure (MAP), TG, and high-density lipoprotein cholesterol (HDL-C) with gestational hypertensive disorders; BMI, fasting plasma glucose (FPG), and TG with GDM (all p values < 0.05). The cutoff point values for the above-mentioned MetS components were: TG > 138 mg/dl and BMI < 21 kg/m² for the occurrence of preterm birth; TG > 148 mg/dL, MAP > 84, and HDL-C < 84 mg/dl for gestational hypertensive disorders; BMI > 25 kg/m², FPG > 84 mg/dl, and TG > 161 mg/dl for GDM.

CONCLUSION

The study findings imply the importance of early management of metabolic syndrome in pregnancy to improve maternal-fetal outcomes.

Intrapartum Factors Affecting Abnormal Lipid Profiles in Early Postpartum Period

The aim of this research is to investigate the risk factors during pregnancy affect abnormal lipid profiles in women with early postpartum period. This was a single-center retrospective study including 869 women who delivered between December 2017 and May 2019. We collected total cholesterol levels, both at 24–28 GWs and 1 month before delivery. Lipid profiles such as total cholesterol, high-density lipoprotein (HDL), triglyceride (TG) and low-density lipoprotein (LDL) at 6 weeks after delivery were retrieved. Subjects were categorized into 3 groups such as normal, borderline and abnormal group according to the lipid profile levels. The risk factors associated with borderline to abnormal HDL level were body mass index (BMI) of pre-pregnancy (OR = 1.182, 95% CI: 1.116–1.252, p < 0.001), weight gain during pregnancy (OR = 1.085, 95% CI: 1.042–1.131, p < 0.001) and hypertension (HTN) (OR = 3.451, 95% CI: 1.224–9.727, p = 0.02). The risk factors associated with borderline or abnormal TG were BMI of pre-pregnancy, weight gain during pregnancy and weight reduction after delivery. HTN was associated with borderline to abnormal TG in postpartum (OR = 2.891, 95% CI: 1.168–7.156, p = 0.02), while GDM correlated purely with abnormal TG in postpartum (OR = 2.453, 95% CI: 1.068–5.630, p = 0.03). Abnormal lipid profiles in postpartum were significantly associated with BMI of pre-pregnancy, weight gain during pregnancy and weight reduction after delivery. In addition, pregnancy-related HTN was highly associated with abnormal HDL level, and GDM was associated with abnormal TG level in the early postpartum period.

Preconception Cardiometabolic Markers and Birth Outcomes Among Women in the Hispanic Community Health Study/Study of Latinos

Background: Associations between preconception cardiometabolic markers and birth outcomes have been noted, but data are scarce for Hispanics/Latinos. We examined the association between preconception cardiometabolic markers, birthweight and preterm birth among U.S. Hispanic/Latina women. Materials and Methods: The Hispanic Community Health Study/Study of Latinos is a cohort study of U.S. adults 18-74 years of age, including 3,798 women of reproductive age (18-44 years) from four field centers representing Hispanic/Latino backgrounds of Cuban, Dominican, Mexican, Puerto Rican, Central American, and South American. A baseline clinic examination (2008-2011) and a second clinic examination (2014-2017), including ascertainment of birth outcomes, allowed for identification of 517 singleton live births between the exams. Preconception cardiometabolic markers included abdominal obesity (waist circumference ≥88 cm), body mass index >30 kg/m2, high blood pressure (systolic ≥120 mmHg and diastolic ≥80 mmHg), elevated triglycerides (≥150 mg/dL), low high-density lipoprotein cholesterol (<50 mg/dL), elevated fasting glucose (≥100 mg/dL), and insulin. Complex survey linear regression modeled the association between cardiometabolic markers and birthweight-for-gestational age z-score; complex survey logistic regression modeled the association with preterm birth. Analyses adjusted for Hispanic/Latina background, field center, years between baseline and birth, age, and nulliparity. Results: In adjusted linear regression models, elevated fasting glucose was associated with higher birthweight z-scores (β = 0.56, 95% confidence interval [95% CI] 0.14 to 0.99), even after further adjustment for maternal percent body fat (β = 0.53, 95% CI 0.10 to 0.95). In adjusted logistic regression models, high blood pressure (odds ratio [OR] = 2.57, 95% CI 1.13 to 5.88) and increased insulin (OR = 1.50, 95% CI 1.06 to 2.14, for a 10 mU/L increase) were associated with higher odds for preterm birth. Conclusions: Infant birthweight and preterm birth may be influenced by selected cardiometabolic risk factors before pregnancy among Hispanic/Latina women.

Associations of maternal lipoprotein particle distribution in mid-pregnancy with birth outcomes: a pilot study

Background

An excessive rise in maternal lipids during pregnancy may have detrimental impacts on maternal and fetal health leading to adverse pregnancy outcomes. However, knowledge gaps exist with respect to the association between lipid biomarkers and birth outcomes.

Methods

We conducted a secondary data analysis of healthy pregnant women (N = 25) with mid-pregnancy fasting serum samples collected at 22–28 weeks of gestation and birth outcome data. Serum was analyzed for conventional lipid profile (total-C, HDL-C, LDL-C, and triglycerides) and lipoprotein subclass distribution, including particle number (nM) and size (nm), for very low-density lipoprotein (VLDL)/chylomicron (CM), low density lipoprotein (LDL), and high-density lipoprotein (HDL), by nuclear magnetic resonance spectroscopy.

Associations between maternal lipids and birth outcomes, including birth weight (g) and gestational age (weeks), were assessed using multivariable linear regression, adjusted for pre-pregnancy BMI.

Results

Although conventional lipids were not associated (p > 0.05) with birth outcomes, every 1-unit increment in large VLDL/CM particles (nM) and VLDL/CM size (nm) was associated with an increase in birth weight (confounder-adjusted β-coefficient, 45.80 g [5.30, 86.20, p = 0.003] and 24.90 g [8.80, 40.90, p = 0.002], respectively). Among the HDL subclass parameters, a 1-unit (nM) increase in the concentration of total HDL-particles was associated with a reduced birth weight (confounder adjusted β-coefficient, -19.40 g [95% confidence interval, -36.70, -2.20]; p = 0.03) after adjustment for maternal pre-pregnancy BMI.

Conclusion

The preliminary results of this pilot study suggest that total particle concentrations of VLDL/CM and HDL in mid-pregnancy have divergent associations with birth weight, potentially reflecting the specific roles of these lipoprotein particles with respect to placental function and fetal growth.

Biomarkers of pre-pregnancy allostatic load and subsequent adverse birth outcomes

Racial disparities in birth outcomes are seemingly intractable. Using person-centered methods and drawing from the life course and Weathering Hypothesis literatures, we used data from the National Longitudinal Study of Adolescent to Adult Health to group non-Hispanic White and non-Hispanic Black women ages 24–34 into latent classes based on pre-pregnancy biomarkers of allostatic load. Stratified analyses yielded four latent classes among non-Hispanic White women, characterized by: 1) high blood pressure, 2) high body mass index and waist circumference, 3) high total cholesterol and triglycerides, and low high-density lipoprotein, and 4) low-risk, and two latent classes among non-Hispanic Black women, characterized by: 1) high body mass index and waist circumference, and moderate-risk blood pressure, hbA1c, and c-reactive protein, and 2) low-risk. Allostatic load class membership and other maternal- and infant-level covariates were then included simultaneously as predictors of three separate dichotomous outcomes: preterm birth, macrosomia, and low birth weight in multilevel logistic regression models. In a separate multilevel linear regression model, the same variables were simultaneously entered to predict continuously measured birthweight. In multilevel, multivariate models, White women in the high-risk body mass index and waist circumference class, as compared to the high-risk blood pressure class, had infants with higher birthweights. Other comparisons were not significant or not of meaningful magnitude. Prioritizing temporality so that allostatic load measurement preceded first birth likely biased the composition of the analytical sample. Additional research is needed to help medical providers and public health practitioners understand the complex biological and social mechanisms underlying inequities in birth outcomes and identify prevention strategies.

•

White women were characterized by 4 classes of biomarkers of pre-pregnancy health. Black women were characterized by 2 classes of biomarkers of pre-pregnancy health.

•

Black (v White) women were 2x as likely to have a preterm or low birthweight birth.

•

White women in the high-risk BMI and WC class, as compared to the high-risk BP class, had infants with higher birthweights.

•

Other allostatic load class comparisons were not significant or not of meaningful magnitude.

•

Overall, the allostatic load classes were not associated with birth outcomes.

Lipid and lipoprotein concentrations during pregnancy and associations with ethnicity

Background

To describe ethnic differences in concentrations of lipids and lipoproteins, and their changes, during pregnancy to postpartum.

Methods

This was a population-based cohort study conducted in primary antenatal care in Norway. The participants (n = 806) were healthy, pregnant women, 59% were ethnic minorities. Outcomes were triglycerides, total cholesterol, HDL- and LDL-cholesterol, analysed from fasting blood samples drawn at gestational age (weeks) 15, 28 and 14 weeks postpartum. We performed linear regression models and linear mixed models to explore the total effect of ethnicity on the outcomes, adjusting for gestational age /week postpartum, maternal age and education. The analyses are corrected for multiple testing using the Bonferroni correction.

Results

At gestational age 15, triglyceride concentrations were lower in women of African origin (1.03 mmol/mol (95% CI: 0.90, 1.16)) and higher in women of South Asian (primarily Pakistan and Sri Lanka) origin (1.42 mmol/mol (1.35, 1.49)) and East Asian (primarily Vietnam, Philippines and Thailand) origin (1.58 mmol/mol (1.43, 1.73)) compared with Western Europeans (1.26 mmol/mol (1.20, 1.32)). Women of Asian and African origin had a smaller increase in triglycerides, LDL- and total cholesterol from gestational age 15 to 28. At gestational age 28, LDL-cholesterol levels were lowest among East Asians (3.03 mmol/mol (2.72, 3.34)) compared with Western Europeans (3.62 mmol/mol (3.50, 3.74)). Triglycerides and HDL-cholesterol were lower postpartum than at gestational age 15 in all groups, but the concentration of LDL-cholesterol was higher, except in Africans. South and East Asian women had lower HDL-cholesterol and higher triglycerides postpartum, while African women had lower triglycerides than Western Europeans.

Conclusion

We found significant differences in the concentrations of lipids and lipoproteins and their changes during pregnancy and the early postpartum period related to ethnic origin.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-022-04524-2.

Maternal hyperlipidemia and spontaneous preterm delivery: a multi-centre cohort study

BACKGROUND

Hyperlipidemia is a precursor of inflammation and oxidative stress and suggested to be associated with adverse pregnancy outcomes such as preterm delivery. This study evaluated the association between maternal hyperlipidemia and spontaneous preterm delivery.

METHODS

This was a prospective, multicentre cohort study in which 239 pregnant women aged 20-35 years with singleton pregnancy, were consecutively recruited at estimated gestational ages of 14-18weeks. Maternal serum lipids were determined at recruitment over a 2-month period and they were followed up until 37 weeks for the subsequent 6 months. Pregnant women with medical conditions and medications that could alter serum lipid levels were excluded from the study. Demographic and baseline variables were summarized using descriptive statistics. Comparison of continuous variables was done using the student's t-test and categorical variables were compared using the Chi square or Fisher's exact test as appropriate. Correlation was determined using Pearson's correlation. Odd ratios were calculated at 95% confidence interval, width of CI as 10% (0.1) and all significances are reported at p < .05.

FINDINGS

The prevalence of spontaneous preterm delivery and maternal hypercholesterolemia was 10.2% and 33.1% respectively. There was no significant association between spontaneous preterm delivery and hyperlipidemia in pregnancy (p = .102). Mean serum total cholesterol (mmol/L), LDL cholesterol (mmol/L), HDL cholesterol (mmol/L) and triglyceride (mmol/L) was 5.31 ± 0.84, 2.60 ± 0.72, 1.64 ± 0.36 and 1.23 ± 0.40 respectively in women with spontaneous preterm delivery was similar to mean values of 5.23 ± 0.98, 2.54 ± 0.82, 1.64 ± 0.49 and 1.30 ± 0.59 respectively in women with term delivery. There was no significant correlation between mean individual serum lipids, determined at 14-18weeks gestational age, and gestational age at delivery.

CONCLUSION

Serum lipid values determined early in pregnancy were observed to be similar in women with preterm and term delivery. There was no association between hyperlipidemia and spontaneous preterm delivery. There was no correlation of individual mean lipid values, determined early in pregnancy, and gestational age at delivery.

Functional changes in decidual mesenchymal stem/stromal cells are associated with spontaneous onset of labour

Ageing and parturition share common pathways, but their relationship remains poorly understood. Decidual cells undergo ageing as parturition approaches term, and these age-related changes may trigger labour. Mesenchymal stem/stromal cells (MSCs) are the predominant stem cell type in the decidua. Stem cell exhaustion is a hallmark of ageing, and thus ageing of decidual MSCs (DMSCs) may contribute to the functional changes in decidual tissue required for term spontaneous labour. Here, we determine whether DMSCs from patients undergoing spontaneous onset of labour (SOL-DMSCs) show evidence of ageing-related functional changes compared with those from patients not in labour (NIL-DMSCs), undergoing Caesarean section. Placentae were collected from term (37-40 weeks of gestation), SOL (n = 18) and NIL (n = 17) healthy patients. DMSCs were isolated from the decidua basalis that remained attached to the placenta after delivery. DMSCs displayed stem cell-like properties and were of maternal origin. Important cell properties and lipid profiles were assessed and compared between SOL- and NIL-DMSCs. SOL-DMSCs showed reduced proliferation and increased lipid peroxidation, migration, necrosis, mitochondrial apoptosis, IL-6 production and p38 MAPK levels compared with NIL-DMSCs (P < 0.05). SOL- and NIL-DMSCs also showed significant differences in lipid profiles in various phospholipids (phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, phosphatidylserine), sphingolipids (ceramide, sphingomyelin), triglycerides and acyl carnitine (P < 0.05). Overall, SOL-DMSCs had altered lipid profiles compared with NIL-DMSCs. In conclusion, SOL-DMSCs showed evidence of ageing-related reduced functionality, accumulation of cellular damage and changes in lipid profiles compared with NIL-DMSCs. These changes may be associated with term spontaneous labour.

A Novel Review of Homocysteine and Pregnancy Complications

Homocysteine (Hct) is a substance produced in the metabolism of methionine. It is an essential type of amino acid gained from the daily diet. Methylenetetrahydrofolate reductase (MTHFR) gene mutation is related to elevated total homocysteine (tHct) expressions, in particular, among women with low folate intake. Hyperhomocysteinemia (HHct) is caused by numerous factors, such as genetic defects, lack of folic acid, vitamin B₆ and B₁₂ deficiency, hypothyroidism, drugs, aging, and renal dysfunction. Increased Hct in peripheral blood may lead to vascular illnesses, coronary artery dysfunction, atherosclerotic changes, and embolic diseases. Compared to nonpregnant women, the Hct level is lower in normal pregnancies. Recent studies have reported that HHct was associated with numerous pregnancy complications, including recurrent pregnancy loss (RPL), preeclampsia (PE), preterm delivery, placental abruption, fetal growth restriction (FGR), and gestational diabetes mellitus (GDM). Besides, it was discovered that neonatal birth weight and maternal Hct levels were negatively correlated. However, a number of these findings lack consistency. In this review, we summarized the metabolic process of Hct in the human body, the levels of Hct in different stages of normal pregnancy reported in previous studies, and the relationship between Hct and pregnancy complications. The work done is helpful for obstetricians to improve the likelihood of a positive outcome during pregnancy complications. Reducing the Hct level with a high dosage of folic acid supplements during the next pregnancy could be helpful for females who have suffered pregnancy complications due to HHct.

Second-trimester and third-trimester maternal lipid profiles significantly correlated to LGA and macrosomia

BACKGROUND

According to the theory of fetal-derived adult diseases, abnormal fetal development might affect the occurrence of diseases in adulthood, and appropriate fetal growth status intrauterine might have a beneficial effect on it. To adapt properly for fetal development, there are numerous changes in the maternal physiology during pregnancy, including blood lipid metabolism. The aim of this study is to evaluate the association between lipid profiles in the second and third trimesters of normal pregnancy and fetal birth weight.

MATERIALS AND METHODS

The study population was derived from 5695 pregnant women, who maintained routine prenatal care at the women's hospital of Zhejiang University, School of medicine January 1, 2014, and December 31, 2014. The pregnant women in this study all carried uncomplicated singleton pregnancies to at least 37 weeks.

RESULTS

The mean (standard deviation) birth weight was 3361.00 (385.94) g; 413 (7.3%) of the infants were large for gestational age, and 330 (5.8%) were macrosomia. On multiple linear regression analysis, positive determinants of birth weight were gravidity, parity, gestational age at delivery, male infant, maternal height, and weight before pregnancy, weight gain during pregnancy, fasting blood glucose (FBG) level, second-trimester cholesterol (TC) and third-trimester triglyceride (TG), gestational albumin (ALB), and third-trimester high-density lipoprotein (HDL-C) levels were each negatively associated with birth weight. On logistic regression analysis, the significant metabolic lipid predictors of delivering a large-for-gestational-age infant were second- and third-trimester TG (aOR = 1.178, 95% CI 1.032-1.344, p = 0.015; aOR = 1.106, 95% CI 1.043-1.173, p = 0.001, respectively) and second- and third-trimester HDL-C level (aOR = 0.655, 95% CI 0.491-0.874, p = 0.004; aOR = 0.505, 95% CI 0.391-0.651, p < 0.001, respectively). Third-trimester TG and HDL-C were stable predictors of large-for-gestational-age infants in stratification analysis. High TG and low HDL-C level during third trimester could be considered as indicators of a high risk of large for gestational age (LGA) and macrosomia, regardless of infant gender.

CONCLUSION

These results suggest that future lifestyle programs in women of reproductive age with a focus on lowering TG levels (i.e., diet, weight reduction, and physical activity) may help to reduce the incidence of LGA and macrosomia.

Association of high maternal triglyceride levels early and late in pregnancy with adverse outcomes: A retrospective cohort study

BACKGROUND

Excess maternal triglyceride (mTG) exposure during early or late pregnancy increases risks of adverse pregnancy outcomes. However, it is inconclusive whether persistently high maternal triglyceride during whole pregnancy has more negative associations.

OBJECTIVE

To explore whether persistently high maternal triglyceride (mTG) levels from early to late pregnancy further increases the risk of adverse pregnancy outcomes.

METHODS

We included 12,715 women who had a singleton birth and who underwent routine serum lipid screenings in both early (9-13 weeks) and late (28-42 weeks) pregnancy during May 2018 to July 2019 in a university-based maternity center. Risks for gestational diabetes mellitus (GDM), preeclampsia, preterm delivery, small/large for gestational age (LGA) were estimated.

RESULTS

Elevated mTG levels during early pregnancy were associated with increased risks of preterm delivery (AOR, 1.52; 95% CI, 1.21 to 1.90), preeclampsia (1.75; 1.29 to 2.36), gestational diabetes mellitus (1.95; 1.69 to 2.25), and LGA (1.28; 1.12 to 1.46). Compared with those with low mTG levels both in the 1st and 3rd trimesters, persistently high mTG levels increased the risks of preeclampsia (2.53; 1.66 to 3.84), GDM (1.97; 1.57 to 2.47), and LGA (1.68; 1.37 to 2.07). However, persistently high mTG levels only slightly increased risk of LGA when compared with high mTG levels during the 1st trimester alone (1.34, 1.01 to 1.77).

CONCLUSIONS

Elevated mTG levels during early pregnancy not in late pregnancy could be the crucial risk factor associated with adverse pregnancy outcomes. These results suggest the importance of lipid screenings and preventions during early pregnancy, which may help to improve pregnancy outcomes.

Maternal Serum Lipid Trajectories and Association with Pregnancy Loss and Length of Gestation

OBJECTIVE

We characterized lipid trajectories and investigated lipids and rate of pregnancy lipid change with the risk of pregnancy loss or preterm delivery <37 weeks.

STUDY DESIGN

In a secondary analysis of 337 women with one to two prior losses assigned to placebo in a randomized controlled trial at four centers (2007-2012), cholesterol, low- and high-density lipoprotein cholesterol (HDL-C), and triglycerides were measured up to 6 months prepregnancy (time 0) and pregnancy up to 7 visits. Trajectories were created using linear mixed models. Multivariable logistic regression with adjustment for maternal characteristics and cholesterol was performed.

RESULTS

Lipids decreased from prepregnancy to 4 to 5 weeks, followed by an increase, and were biphasic or triphasic depending on the lipid component. Between 4 and 8 weeks, for every 1-unit increase in HDL-C, there was a 22% decreased odds of loss <14 weeks (odds ratio: 0.78; 95% confidence interval: 0.60, 0.99) and 24% decreased odds of loss or preterm delivery 14 to <37 weeks (odds ratio: 0.76; 95% confidence interval: 0.60, 0.96).

CONCLUSION

There were no associations with other lipid components or other time points. An impaired rise of HDL-C early in pregnancy may signal maladaptation to pregnancy that is associated with pregnancy loss or preterm delivery.

Lipidome Profiles Are Related to Depressive Symptoms and Preterm Birth Among African American Women

African American women have the highest rate of preterm birth (PTB; <37 completed weeks' gestation) of any racial and ethnic group in the United States (14.1%). Depressive symptoms (DS) have been linked to PTB risk of African American women. We hypothesized that maternal lipidomic profiles are related to prenatal DS and gestational age at birth among African American women. Women were enrolled at 9-25 weeks' gestation, completed questionnaires, and provided plasma samples. Lipidomic profiles were determined by "shotgun" Orbitrap high-resolution/accurate mass spectrometry. Data were analyzed using SIMCA P+ software. There was a clear separation in the orthogonal projections to latent structures discriminant analysis score plot between women with Center for Epidemiologic Studies Depression Scale (CES-D) scores ≥23 and women with CES-D scores ≤22. Similarly, a clear separation was observed in the model between PTB and full-term birth. Corresponding S-plot, loading plot, and variable importance in projection plot/list were used to identify the lipids responsible for the groupings. Higher levels of specific triglyceride (TG) species and lower levels of specific phosphatidylcholines (PCs) PC(37:1), PC(41:6), and PC(39:3) were associated with PTB. PC PC(37:1) levels were also lower among women with CES-D scores ≥23, pointing toward a possible connection between DS and PTB. Although overweight pregnant women showed higher levels of TGs, the PTB model showed specific TGs unique to PTB. Lipidomic profiles in pregnant African American women are related to DS, and our data suggest a role for specific TGs and PCs in PTB.

Cardiovascular Disease-Related Pregnancy Complications Are Associated with Increased Maternal Levels and Trajectories of Cardiovascular Disease Biomarkers During and After Pregnancy

Background: Having a pregnancy complicated by hypertensive disorders of pregnancy (HDP) and/or having a small or preterm baby put a woman at risk for later cardiovascular disease (CVD). It is uncertain if higher maternal CVD risk factors (reflected by increased peripartum CVD biomarker levels) account for this risk, or if experiencing a complicated pregnancy itself increases a woman's CVD risk (reflected by an increase in biomarker trajectories from early pregnancy to postpartum). Methods: We conducted a secondary analysis of an 8-week mindful eating and stress reduction intervention in 110 pregnant women. We used mixed linear regression analysis to compare CVD biomarker levels and trajectories, between women with and without a CVD-related pregnancy complication (including HDP [gestational hypertension or preeclampsia] or having a small for gestational age [<10th percentile] or preterm [<37 weeks] baby), at three times: (1) 12-20 weeks of gestation, (2) 3 months postpartum, and (3) 9 months postpartum. CVD biomarkers studied included serum glucose, insulin, homeostasis model assessment of insulin resistance (HOMA-IR), body mass index (BMI), blood pressure (BP), interleukin-6 (IL-6), tumor necrosis factor, and lipids. We adjusted for age, maternal smoking, prepregnancy BMI, BP, age × time, and BMI × time. Results: Women had a mean age of 28 years (standard deviation [SD] 6), mean prior pregnancies of 0.8 (SD 1.0), and 22 women had one or more CVD-related pregnancy complications. HOMA-IR, diastolic BP, triglyceride, high-density lipoprotein cholesterol, and IL-6 average levels, but not trajectories, differed among women with complicated versus normal pregnancy (all p values were ≤0.04). Peripartum glucose and systolic BP trajectories were statistically greater in complicated versus normal pregnancies (p values were 0.008 and 0.01, respectively). Conclusion: We conclude that the experience of a complicated pregnancy in addition to elevated CVD risk factor levels may both increase a woman's risk of future CVD. ClinicalTrials.gov Identifier: NCT01307683.

A successful term pregnancy with severe hypertriglyceridaemia and acute pancreatitis. Clinical management and review of the literature

BACKGROUND AND AIMS

Acute hyperlipidaemic pancreatitis (HP) may develop in pregnancy in patients with genetic predisposition. There are no accepted guidelines for the management of this rare but life-threatening condition in pregnancy. Plasma exchange (PEX) was suggested as a suitable option to treat HP in pregnancy; however, further evidence from case reports/case series are needed.

METHODS

Three PEX procedures (2000 ml of plasma replaced with 5% albumin) were performed in one week in a pregnant patient at 25 weeks of gestational age with severe HP. Triglyceride related genes (LPL, APOA5, APOE, GPIHBP1, GPD1, LMF1, CREB3L3) were screened by DNA sequencing. Medline and Embase databases were searched electronically in January 2018 using different combinations of the relevant medical subject headings for "pancreatitis in pregnancy" and "therapeutic apheresis".

RESULTS

Gene profiling assessed a combined heterozygous state for the variants pSer19Trp of the APOA5 gene and pCys130Arg of the APOE (allele E4) gene. PEX led to significant and progressive reduction of triglyceride plasma levels along with cholesterol and C-reactive protein. Meanwhile a fast improvement of pregnant clinical condition was observed. This allowed the delivery at term of a healthy newborn without gestational complications. An outcome hardly achievable in patients managed exclusively by a pharmacological approach.

CONCLUSIONS

PEX led to a positive maternal outcome in absence of foetal and gestational complications in a case of severe HP in pregnancy. As clinical trials are lacking, case reports still represent the best way to reasonably implement clinical management of this rare but life-threatening disease.

Early pregnancy immune profile and preterm birth classified according to uteroplacental lesions

INTRODUCTION

Preterm birth is a heterogeneous phenotype, with placental abnormalities underlying many cases. The etiology of preterm births that occur in the absence of placental abnormalities, however, remain enigmatic and we considered that early pregnancy biomarkers may provide clues.

METHODS

Women from a hospital-based cohort (2008-2012, n = 397) were randomly selected within 6 strata of term and preterm birth with and without placental decidual vasculopathy (arteriopathy), intrauterine inflammation/infection (acute chorioamnionitis), or no lesions. Lipids and inflammatory markers were analyzed in first trimester samples (12.5 ± 0.6 weeks) and related to outcome groups (referent, term births with no lesions). Factor analysis then clustered analytes and related these to preterm birth groups, adjusted for covariates and stratified by pre-pregnancy obesity.

RESULTS

Three biomarker patterns were identified. Immune activation cytokines (33% of the variance) were associated with preterm birth with no lesions (aOR 1.5, 95%CI 1.1-2.1), particularly among obese women. In contrast, inflammatory chemokines (9% of variance) were associated with term and preterm vasculopathy among non-obese women (aOR 2.6 [1.3, 4.7] and 2.0 [1.1, 3.0], respectively).

DISCUSSION

The early pregnancy maternal immune profile is related to preterm births classified according to placental lesions, and these associations vary according to obesity status.

Maternal High Triglyceride Levels During Early Pregnancy and Risk of Preterm Delivery: A Retrospective Cohort Study

CONTEXT

Maternal obesity increases the risk of preterm delivery. Obesity is known to be associated with altered lipid metabolism.

OBJECTIVE

To investigate the associations between high maternal triglyceride (mTG) levels during early pregnancy and risks of preterm delivery stratified by early pregnancy body mass index (BMI).

DESIGN

Retrospective cohort study.

SETTING

University-based maternity center.

PATIENTS

49,612 women with singleton pregnancy who underwent fasting serum lipid screening during early pregnancy.

MAIN OUTCOME MEASURES

Risk of preterm delivery (total, <37 weeks; early, 28 to 33 weeks; and late, 34 to 36 weeks).

RESULTS

Among women enrolled, 2494 had a preterm delivery, including 438 early preterm and 2056 late preterm delivery. High mTG (>90th percentile, 2.04 mM) was associated with shortened gestation. Risks of total, early, and late preterm deliveries increased with mTG levels, and the high mTG-related risk was highest for early preterm delivery [adjusted odds ratio (AOR) 1.72; 95% CI, 1.30 to 2.29]. After stratification by BMI, high mTG was associated with risk of preterm delivery in both overweight or obese (OWO) women (AOR 1.32; 95% CI, 1.02 to 1.70) and women with normal BMI (AOR 1.36; 95% CI, 1.16 to 1.59). In additional sensitivity analyses, we found that high mTG was related to higher risks of preterm delivery among OWO women and women with normal BMI (AOR, 1.54; 95% CI, 1.07 to 2.22 and 1.62, 1.34 to 1.96, respectively), especially early preterm delivery (AOR 2.47; 95% CI, 1.19 to 5.10, and AOR 2.50; 95% CI, 1.65 to 3.78, respectively).

CONCLUSIONS

High mTG level during early pregnancy increased the risks of preterm delivery not only in OWO women but also in women with normal BMI.

Metabolic syndrome in pregnancy and risk for adverse pregnancy outcomes: A prospective cohort of nulliparous women

BACKGROUND

Obesity increases the risk for developing gestational diabetes mellitus (GDM) and preeclampsia (PE), which both associate with increased risk for type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD) in women in later life. In the general population, metabolic syndrome (MetS) associates with T2DM and CVD. The impact of maternal MetS on pregnancy outcomes, in nulliparous pregnant women, has not been investigated.

METHODS AND FINDINGS

Low-risk, nulliparous women were recruited to the multi-centre, international prospective Screening for Pregnancy Endpoints (SCOPE) cohort between 11 November 2004 and 28 February 2011. Women were assessed for a range of demographic, lifestyle, and metabolic health variables at 15 ± 1 weeks' gestation. MetS was defined according to International Diabetes Federation (IDF) criteria for adults: waist circumference ≥80 cm, along with any 2 of the following: raised trigycerides (≥1.70 mmol/l [≥150 mg/dl]), reduced high-density lipoprotein cholesterol (<1.29 mmol/l [<50 mg/dl]), raised blood pressure (BP) (i.e., systolic BP ≥130 mm Hg or diastolic BP ≥85 mm Hg), or raised plasma glucose (≥5.6 mmol/l). Log-binomial regression analyses were used to examine the risk for each pregnancy outcome (GDM, PE, large for gestational age [LGA], small for gestational age [SGA], and spontaneous preterm birth [sPTB]) with each of the 5 individual components for MetS and as a composite measure (i.e., MetS, as defined by the IDF). The relative risks, adjusted for maternal BMI, age, study centre, ethnicity, socioeconomic index, physical activity, smoking status, depression status, and fetal sex, are reported. A total of 5,530 women were included, and 12.3% (n = 684) had MetS. Women with MetS were at an increased risk for PE by a factor of 1.63 (95% CI 1.23 to 2.15) and for GDM by 3.71 (95% CI 2.42 to 5.67). In absolute terms, for PE, women with MetS had an adjusted excess risk of 2.52% (95% CI 1.51% to 4.11%) and, for GDM, had an adjusted excess risk of 8.66% (95% CI 5.38% to 13.94%). Diagnosis of MetS was not associated with increased risk for LGA, SGA, or sPTB. Increasing BMI in combination with MetS increased the estimated probability for GDM and decreased the probability of an uncomplicated pregnancy. Limitations of this study are that there are several different definitions for MetS in the adult population, and as there are none for pregnancy, we cannot be sure that the IDF criteria are the most appropriate definition for pregnancy. Furthermore, MetS was assessed in the first trimester and may not reflect pre-pregnancy metabolic health status.

CONCLUSIONS

We did not compare the impact of individual metabolic components with that of MetS as a composite, and therefore cannot conclude that MetS is better at identifying women at risk. However, more than half of the women who had MetS in early pregnancy developed a pregnancy complication compared with just over a third of women who did not have MetS. Furthermore, while increasing BMI increases the probability of GDM, the addition of MetS exacerbates this probability. Further studies are required to determine if individual MetS components act synergistically or independently.

Maternal plasma cholesterol concentration and preterm birth: a meta-analysis and systematic review of literature

Background: Women that previously had preterm labor are at an increased risk for heart disease. Because spontaneous preterm birth is an adverse pregnancy outcome that affects millions of children worldwide, our objective was to review and analyze studies that have examined associations between maternal total cholesterol (TC), LDL-C, and HDL-C concentrations during pregnancy and the risk of preterm birth to potentially define biomarkers or targets for treatment.Method: A search was performed and 22 articles were found that examined the association of maternal plasma cholesterol concentrations and preterm birth. A meta-analysis was performed on 10 of the articles, those that used maternal lipid concentrations as the outcome and presented results as means plus variables, and a qualitative review was performed on all 22 articles.Results: The meta-analysis showed no relationship between maternal TC, LDL-C, or HDL-C and increased risk of preterm birth, although, a near significant relationship between low maternal HDL-C concentration and preterm birth (p = .055). Importantly, associations increased when cholesterol concentrations were combined with inflammatory markers or metabolic syndrome factors.Conclusions: The relationship between maternal cholesterol levels and preterm birth is heterogeneous. Associations are strengthened when maternal cholesterol concentrations are combined with other factors that may be related to more recently defined lipoprotein functions.

Distribution of Fatty Acids and Lipids During Pregnancy

Maternal fatty acid and lipid metabolism undergoes changes during pregnancy to facilitate fetal growth and development. Different types of fatty acids have different roles in maintaining a successful pregnancy and they are incorporated into different forms of lipids for the purpose of storage and transport. This chapter aims to provide an understanding of the distribution and metabolism of fatty acids and lipids in the maternal, placental, and fetal compartments. We further describe how this distribution is altered in maternal obesity, preterm birth, and pregnancy complications such as gestational diabetes mellitus, preeclampsia, and intrauterine growth restriction.

The association between HIV (treatment), pregnancy serum lipid concentrations and pregnancy outcomes: a systematic review

BACKGROUND

Observed adverse effects of antiretroviral therapy (ART) on the lipid profile could be of significance in pregnancy. This systematic review aims to summarize studies that investigated the association between HIV, ART and serum lipids during pregnancy and adverse pregnancy outcomes.

METHODS

A systematic search was conducted in five electronic databases to obtain articles that measured serum lipid concentrations or the incidence of dyslipidaemia in HIV-infected pregnant women. Included articles were assessed for quality according to the Cochrane Risk of Bias Tool. The extracted data was analysed through descriptive analysis.

RESULTS

Of the 1264 articles screened, 17 articles were included in this review; eleven reported the incidence of dyslipidaemia, and twelve on maternal serum lipid concentrations under the influence of HIV-infection and ART. No articles reported pregnancy outcomes in relation to serum lipids. Articles were of acceptable quality, but heterogenic in methods and study design. Lipid levels in HIV-infected women increased 1.5-3 fold over the trimesters of pregnancy, and remained within the physiological reference range. The percentage of women with dyslipidaemia was variable between the studies [0-88.9%] and highest in the groups on first generation protease inhibitors and for women on ART at conception.

CONCLUSION

This systematic review observed physiologic concentrations of serum lipids for HIV-infected women receiving ART during pregnancy. Serum lipids were increased in users of first generation protease inhibitors and for those on treatment at conception. There was no information available about pregnancy outcomes. Future studies are needed which include HIV-uninfected control groups, control for potential confounders, and overcome limitations associated with included studies.