Prepregnancy lipids related to preterm birth risk: the coronary artery risk development in young adults study

Trajectories of cardiovascular risk predict pregnancy outcomes: The Bogalusa Heart Study and the Cardiovascular Risk in Young Finns Study

BACKGROUND

Life course patterns of change in risk-trajectories-affect health.

OBJECTIVES

To examine how trajectories of cardiovascular risk factors are associated with pregnancy and birth outcomes.

METHODS

Data from two cohort studies participating in the International Childhood Cardiovascular Consortium-The Bogalusa Heart Study (BHS; started in 1973, N = 903 for this analysis) and the Cardiovascular Risk in Young Finns Study (YFS; started in 1980, N = 499) were used. Both followed children into adulthood and measured cardiovascular risk factors, including body mass index (BMI), systolic and diastolic blood pressure (SBP/DBP), total, lipoprotein (LDL)- and high density lipoprotein (HDL)-cholesterol and serum triglycerides. Discrete mixture modelling was used to divide each cohort into distinct trajectories according to these risk factors from childhood to early adulthood, and these groups were then used to predict pregnancy outcomes including small for gestational age (SGA; <10th study-specific percentile of gestational age by sex), preterm birth (PTB; <37 weeks' gestation), hypertensive disorders of pregnancy (HDP) and gestational diabetes mellitus (GDM), with control for age at baseline and at first birth, parity, socioeconomic status, BMI and smoking.

RESULTS

The models created more trajectories for BMI, SBP and HDL-cholesterol in the YFS than in BHS, for which three classes generally seemed to be sufficient to represent the groups in the population across risk factors. In BHS, the association between the higher and flatter DBP trajectory and PTB was aRR 1.77, 95% confidence interval [CI] 1.06, 2.96. In BHS the association between consistent total cholesterol and PTB was aRR 2.16, 95% CI 1.22, 3.85 and in YFS the association between elevated high trajectory and PTB was aRR 3.35, 95% CI 1.28, 8.79. Elevated-increasing SBP was associated with a higher risk of GH in BHS and increasing or persistent-obese BMI trajectories were associated with GDM in both cohorts (BHS: aRR 3.51, 95% CI 1.95, 6.30; YFS: aRR 2.61, 95% CI 0.96, 7.08).

CONCLUSIONS

Trajectories of cardiovascular risk, particularly those that represent a consistent or more rapid worsening of cardiovascular health, are associated with a higher risk of pregnancy complications.

Women's Reproductive Milestones and Cardiovascular Disease Risk: A Review of Reports and Opportunities From the CARDIA Study

In 1985 to 1986, the CARDIA (Coronary Artery Risk Development in Young Adults) study enrolled 5115 Black or White participants, including 2788 women, aged 18 to 30 years. Over the following 35 years, the CARDIA study amassed extensive longitudinal data on women's reproductive milestones, spanning menarche to menopause. Although not initially conceived as a study of women's health, >75 CARDIA study publications address relationships between reproductive factors and events with cardiovascular and metabolic risk factors, subclinical and clinical cardiovascular disease, and social determinants of health. The CARDIA study was one of the earliest population-based reports to note Black-White differences in age at menarche and associations with cardiovascular risk factors. Adverse pregnancy outcomes, particularly gestational diabetes and preterm birth, have been assessed along with postpartum behaviors, such as lactation. Existing studies have examined risk factors for adverse pregnancy outcomes and lactation, as well as their relationship to future cardiovascular and metabolic risk factors, diagnoses, and subclinical atherosclerosis. Ancillary studies examining components of polycystic ovary syndrome and ovarian biomarkers, such as anti-Müllerian hormone, have facilitated examination of reproductive health in a population-based cohort of young adult women. As the cohort transitioned through menopause, examination of the importance of premenopausal cardiovascular risk factors along with menopause has improved our understanding of shared mechanisms. The cohort is now aged in the 50s to mid-60s, and women will begin to experience a greater number of cardiovascular events as well as other conditions, such as cognitive impairment. Thus, in the next decade, the CARDIA study will provide a unique resource for understanding how the women's reproductive life course epidemiology informs cardiovascular risk, as well as reproductive and chronological aging.

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.

Considerations for treatment of lipid disorders during pregnancy and breastfeeding

Adequate management of lipid disorders during pregnancy is essential given the association of dyslipidemia with adverse pregnancy outcomes. While there are physiologic changes in lipid levels that occur with normal pregnancy, abnormal alterations in lipids can lead to increased future risk of atherosclerotic cardiovascular disease. There are inherent challenges in the treatment of dyslipidemias during pregnancy and the postpartum period given the lack of adequate data in this population and the contraindication of traditional therapeutic agents. However, it remains of utmost importance to optimize screening and identification of patients at high-risk for atherosclerotic cardiovascular disease so that proper counseling can be provided and the risk for pregnancy complications and downstream cardiovascular complications can be addressed. In this review, we summarize the literature on the association of dyslipidemia in pregnancy with adverse outcomes and discuss considerations for the management of lipid disorders during both pregnancy and breastfeeding.

Lipid metabolism and endometrial receptivity

BACKGROUND

Obesity has now been recognized as a high-risk factor for reproductive health. Although remarkable advancements have been made in ART, a considerable number of infertile obese women still suffer from serial implantation failure, despite the high quality of embryos transferred. Although obesity has long been known to exert various deleterious effects on female fertility, the underlying mechanisms, especially the roles of lipid metabolism in endometrial receptivity, remain largely elusive.

OBJECTIVE AND RATIONALE

This review summarizes current evidence on the impacts of several major lipids and lipid-derived mediators on the embryonic implantation process. Emerging methods for evaluating endometrial receptivity, for example transcriptomic and lipidomic analysis, are also discussed.

SEARCH METHODS

The PubMed and Embase databases were searched using the following keywords: (lipid or fatty acid or prostaglandin or phospholipid or sphingolipid or endocannabinoid or lysophosphatidic acid or cholesterol or progesterone or estrogen or transcriptomic or lipidomic or obesity or dyslipidemia or polycystic ovary syndrome) AND (endometrial receptivity or uterine receptivity or embryo implantation or assisted reproductive technology or in vitro fertilization or embryo transfer). A comprehensive literature search was performed on the roles of lipid-related metabolic pathways in embryo implantation published between January 1970 and March 2022. Only studies with original data and reviews published in English were included in this review. Additional information was obtained from references cited in the articles resulting from the literature search.

OUTCOMES

Recent studies have shown that a fatty acids-related pro-inflammatory response in the embryo-endometrium boundary facilitates pregnancy via mediation of prostaglandin signaling. Phospholipid-derived mediators, for example endocannabinoids, lysophosphatidic acid and sphingosine-1-phosphate, are associated with endometrial receptivity, embryo spacing and decidualization based on evidence from both animal and human studies. Progesterone and estrogen are two cholesterol-derived steroid hormones that synergistically mediate the structural and functional alterations in the uterus ready for blastocyst implantation. Variations in serum cholesterol profiles throughout the menstrual cycle imply a demand for steroidogenesis at the time of window of implantation (WOI). Since 2002, endometrial transcriptomic analysis has been serving as a diagnostic tool for WOI dating. Numerous genes that govern lipid homeostasis have been identified and, based on specific alterations of lipidomic signatures differentially expressed in WOI, lipidomic analysis of endometrial fluid provides a possibility for non-invasive diagnosis of lipids alterations during the WOI.

WIDER IMPLICATIONS

Given that lipid metabolic dysregulation potentially plays a role in infertility, a better understanding of lipid metabolism could have significant clinical implications for the diagnosis and treatment of female reproductive disorders.

Adverse pregnancy outcomes are associated with an increased risk of postpartum prediabetes and diabetes in Chinese women with gestational diabetes

AIMS

To explore associations between adverse pregnancy outcomes and risk of postpartum diabetes and prediabetes among Chinese women with gestational diabetes mellitus (GDM).

METHODS

A total of 507 women with GDM who participated in a randomized controlled trial were successfully followed up at a median of 9.1  (interquartile range: 7.7-11.3) weeks after delivery and underwent a 75 g 2-h oral glucose tolerance test. GDM was diagnosed according to the International Association of Diabetes and Pregnancy Study Group's criteria. Postpartum diabetes and prediabetes were defined by the World Health Organization's. Generalized logit model was used to obtain odds ratios (OR) and 95% confidence interval (CI) of adverse pregnancy outcomes for postpartum diabetes, prediabetes and abnormal glucose regulation (AGR).

RESULTS

Of 507 women with GDM, 3.7% (19) women developed postpartum diabetes, 35.1% (178) women developed postpartum prediabetes. Preterm birth was associated with increased risk of postpartum prediabetes and AGR (adjusted OR: 3.24, 95%CI: 1.48-7.07 & 3.16, 1.46-6.85). Low birth weight was associated with the risk of postpartum prediabetes, diabetes and AGR (adjusted OR: 2.78, 95%CI: 1.13-6.86; 5.21, 1.13-24.02 & 2.99, 1.24-7.21).

CONCLUSIONS

Preterm birth and low birth weight were predictive of postpartum prediabetes, diabetes or AGR in Chinese women with GDM.

Genetic Determinants of Plasma Low-Density Lipoprotein Cholesterol Levels: Monogenicity, Polygenicity, and "Missing" Heritability

Changes in plasma low-density lipoprotein cholesterol (LDL-c) levels relate to a high risk of developing some common and complex diseases. LDL-c, as a quantitative trait, is multifactorial and depends on both genetic and environmental factors. In the pregenomic age, targeted genes were used to detect genetic factors in both hyper- and hypolipidemias, but this approach only explained extreme cases in the population distribution. Subsequently, the genetic basis of the less severe and most common dyslipidemias remained unknown. In the genomic age, performing whole-exome sequencing in families with extreme plasma LDL-c values identified some new candidate genes, but it is unlikely that such genes can explain the majority of inexplicable cases. Genome-wide association studies (GWASs) have identified several single-nucleotide variants (SNVs) associated with plasma LDL-c, introducing the idea of a polygenic origin. Polygenic risk scores (PRSs), including LDL-c-raising alleles, were developed to measure the contribution of the accumulation of small-effect variants to plasma LDL-c. This paper discusses other possibilities for unexplained dyslipidemias associated with LDL-c, such as mosaicism, maternal effect, and induced epigenetic changes. Future studies should consider gene-gene and gene-environment interactions and the development of integrated information about disease-driving networks, including phenotypes, genotypes, transcription, proteins, metabolites, and epigenetics.

Cardiovascular risk factors before and during pregnancy: Does pregnancy unmask or initiate risk?

OBJECTIVES

To understand if pregnancy unmasks previously silent cardiovascular (CV) adverse factors, or initiates lasting injury.

METHODS

Pre-pregnancy and during pregnancy CV risk factors (blood pressure, fasting lipids, and glucose) from 296 women belonging to studies in the International Childhood Cardiovascular Cohort (i3C) Consortium, a group of studies assessing the relationship between child and adolescent CV risk factors and adult outcomes, were used. Correlation coefficients between the pre- and during pregnancy measures were calculated, and the mean difference between the measures was modeled with adjustment for age, body mass index, race, smoking, and study.

RESULTS

Measures were strongly correlated at pre- and during-pregnancy visits (p < 0.01), with r of between 0.30 and 0.55. In most cases, the difference between pre-pregnancy and during-pregnancy did not differ significantly from 0 after adjustment for confounders. Stratification by gestational age indicated stronger correlations with measurements obtained during the first and second trimesters than the third. The correlation did not differ by the time elapsed between the pre-pregnancy and pregnancy visits.

CONCLUSIONS

Pre- and during-pregnancy CV risk factors are moderately well correlated. This may indicate that susceptible women enter pregnancy with higher risk rather than pregnancy inducing new vascular or metabolic effects.

Management of Hypercholesterolemia in Pregnant Women with Atherosclerotic Cardiovascular Disease

PURPOSE OF REVIEW

In this review, we discuss strategies for managing dyslipidemia in pregnant women with ASCVD.

RECENT FINDINGS

Cardiovascular disease (CVD) is the leading cause of mortality in women as well as the leading cause of pregnancy-related mortality in the USA. It is paramount to screen, identify, counsel, and treat women of childbearing age who have existing atherosclerotic disease to mitigate the risks of complications and mortality. Dyslipidemias, including hypercholesterolemia and hyperlipidemia, can further enhance the risk for future CVD events. Treating hypercholesterolemia during pregnancy is crucial, and this is an opportune time for cross-collaboration of subspecialties in cardiology, obstetrics, and gynecology.

Women with multiple gestations have an increased risk of development of hypertension in the future

Background

Multiple gestations are associated with an increased incidence of preeclampsia. However, there exists no evidence for an association between multiple gestations and development of hypertension(HTN) later in life. This study aimed to determine whether multiple gestations are associated with HTN beyond the peripartum period.

Methods

In this retrospective nationwide population-based study, women who delivered a baby between January 1, 2007, and December 31, 2008, and underwent a national health screening examination within one year prior to their pregnancy were included. Subsequently, we tracked the occurrence of HTN during follow-up until December 31, 2015, using International Classification of Diseases-10th Revision codes.

Results

Among 362,821 women who gave birth during the study period, 4,944 (1.36%) women had multiple gestations. The cumulative incidence of HTN was higher in multiple gestations group compared with singleton group (5.95% vs. 3.78%, p < 0.01, respectively). On the Cox proportional hazards models, the risk of HTN was increased in women with multiple gestations (HR 1.35, 95% CI 1.19, 1.54) compared with those with singleton after adjustment for age, primiparity, preeclampsia, atrial fibrillation, body mass index, blood pressure, diabetes mellitus, high total cholesterol, abnormal liver function test, regular exercise, and smoking status.

Conclusions

Multiple gestations are associated with an increased risk of HTN later in life. Therefore, guidelines for the management of high-risk patients after delivery should be established.

Role of Lipid Management in Women's Health Preventive Care

Managing dyslipidemia over a women's life, including a focus on pregnancy, contraception, and atherosclerotic cardiovascular disease risk prevention can decrease the burden of cardiovascular disease.

Patterns of Cardiovascular Risk Factors in the Years Before Pregnancy in Nulliparous Women With and Without Preterm Birth and Small-for-Gestational-Age Delivery

Background Women with either preterm or small-for-gestational-age (SGA) delivery have an elevated lifetime risk of cardiovascular disease that has been attributed to the accrual of vascular risk factors over time. We sought to determine whether an adverse cardiovascular risk factor profile develops in the years before pregnancies complicated by preterm delivery or SGA. Methods and Results Using administrative databases, we identified all 156 278 nulliparous women in Ontario, Canada, who had singleton pregnancies between January 2011 and December 2018 and ≥2 measurements of the following analytes between January 2008 and the start of pregnancy: glycosylated hemoglobin, glucose, lipids, and alanine aminotransferase. There were 11 078 women with preterm delivery and 19 367 with SGA. The 2 most recent pregravid tests were performed at median 0.6 (interquartile range, 0.3-1.4) and 1.9 (interquartile range, 1.1-3.3) years before pregnancy, respectively. Women with preterm delivery had higher pregravid glycosylated hemoglobin, glucose, low-density lipoprotein cholesterol, triglycerides, and alanine aminotransferase, and lower high-density lipoprotein cholesterol, than those without preterm delivery. In contrast, women with SGA had lower pregravid fasting glucose, random glucose, and triglycerides than those without SGA. In the years before pregnancy, women with preterm delivery had higher annual increases than their peers in glycosylated hemoglobin (0.7-times higher), triglycerides (7.9-times higher), and alanine aminotransferase (2.2-times higher). During this time, fasting glucose increased in women who developed preterm delivery but decreased in their peers. Conclusions An adverse cardiovascular risk factor profile evolves over time in the years before pregnancy complicated by preterm delivery, but does not necessarily precede SGA.

The Pregravid Vascular Risk Factor Profile of Low-Risk Women Who Develop Pregnancy Outcomes That Predict Future Cardiovascular Disease

Background: Women with a history of certain adverse outcomes in pregnancy (preterm birth, delivery of a small-for-gestational age [SGA] infant, preeclampsia, and gestational diabetes mellitus [GDM]) have an elevated lifetime prevalence of metabolic syndrome (MetS) and cardiovascular disease, compared with their peers. However, it is not known if MetS precedes the index pregnancy in young, nulliparous women who experience these antepartum outcomes. Thus, we sought to evaluate the relationship between pregravid cardiovascular risk factor profile and these pregnancy outcomes in low-risk women.

Methods: In this prospective preconception cohort study, 1183 newly married women underwent systematic assessment of cardiovascular risk factors (anthropometry, blood pressure, lipids, glucose) at median 24.7 weeks before pregnancy, whereupon they were followed for the outcomes of preterm birth, SGA delivery, preeclampsia, and GDM.

Results: Women who had pregravid MetS (harmonized definition) (n = 49) were more likely to have a Caesarean delivery than their peers (61.4% vs. 38.6%, p = 0.003). However, they did not have a higher incidence of preterm delivery, SGA, preeclampsia, or GDM. Similarly, women who had at least one of these adverse pregnancy outcomes (n = 141) did not have a higher prevalence of MetS or any of its component disorders before pregnancy. Indeed, before pregnancy, there were no significant differences between these women and their peers in waist circumference, body mass index, blood pressure, fasting glucose, triglycerides, low-density-lipoprotein, or high-density-lipoprotein cholesterol.

Conclusions: The adverse cardiovascular risk factor profile that is seen in women with a history of preterm birth, SGA, preeclampsia, or GDM does not necessarily manifest before their pregnancy.

Normotensive preterm delivery and maternal cardiovascular risk factor trajectories across the life course: The HUNT Study, Norway

INTRODUCTION

Preterm delivery (<37 weeks) predicts later cardiovascular disease risk in mothers, even among normotensive deliveries. However, development of subclinical cardiovascular risk before and after preterm delivery is not well understood. We sought to investigate differences in life course cardiovascular risk factor trajectories based on preterm delivery history.

MATERIAL AND METHODS

The HUNT Study (1984-2008) linked with the Medical Birth Registry of Norway (1967-2012) yielded clinical measurements and pregnancy outcomes for 19 806 parous women with normotensive first deliveries. Women had up to three measurements of body mass index, waist-to-hip ratio, blood pressure, lipids, non-fasting glucose, and C-reactive protein during follow up between 21 years before to 41 years after first delivery. Using mixed effects models, we compared risk factor trajectories for women with preterm vs term/postterm first deliveries.

RESULTS

Trajectories overlapped for women with preterm compared with term/postterm first deliveries for all cardiovascular risk factors examined. For instance, the mean difference in systolic blood pressure in women with preterm first deliveries compared with those with term deliveries was 0.2 mm Hg (95% CI -1.8 to 2.3) at age 20 and 1.5 mm Hg (95% CI -0.5 to 3.6) at age 60.

CONCLUSIONS

A history of preterm delivery was not associated with different life course trajectories of common cardiovascular risk factors in our study population. This suggests that the robust association between preterm delivery and cardiovascular end points in Norway or similar contexts is not explained by one or more commonly measured cardiovascular risk factors. Overall, we did not find evidence for a single cardiovascular disease prevention strategy that would reduce risk among the majority of women who had preterm delivery.

Maternal cholesterol levels during gestation: boon or bane for the offspring?

An increase in cholesterol levels is perceived during pregnancy and is considered as a normal adaptive response to the development of the fetus. In some pregnancies, excessive increase in total cholesterol with high levels of Low-Density Lipoprotein leads to maladaptation by the fetus to cholesterol demands, resulting in a pathological condition termed as maternal hypercholesterolemia (MH). MH is considered clinically irrelevant and therefore cholesterol levels are not routinely checked during pregnancy, as a consequence of which there is scarce information on its global prevalence in pregnant women. Studies have reported that MH during pregnancy can cause atherogenesis in adults emphasizing the concept of in utero programming of fetus. Moreover, Gestational Diabetes Mellitus, obesity and Polycystic Ovary Syndrome are potential risk factors which strengthen combined pathologies in placenta and fetuses of mothers with MH. However, lack of conclusive evidence on cholesterol transport and underlying programming demand substantial research to develop population-based life style strategies for women in their childbearing years. The current review focuses on the mechanisms and outcomes of MH from existing epidemiological as well as experimental data and presents a detailed insight on this novel risk factor of cardiovascular diseases.

Life Course Changes in Cardiometabolic Risk Factors Associated With Preterm Delivery: The 30-Year CARDIA Study

Background

Women who deliver preterm infants (<37 weeks) have excess cardiovascular risk; however, it is unclear whether the unfavorable changes in the cardiometabolic profile associated with preterm delivery initiate before, during, or after childbearing.

Methods and Results

We identified 1306 women (51% Black) with births between baseline (1985–1986) and year 30 in the CARDIA (Coronary Artery Risk Development in Young Adults) study. We compared life course changes in blood pressure, body mass index, waist circumference, and lipids in women with preterm deliveries (n=318) with those with all term deliveries (n=988), using piecewise linear mixed‐effects models. Specifically, we evaluated group differences in rates of change before and after the childbearing period and change in level across the childbearing period. After adjusting for the covariates, women with preterm deliveries had a higher change in diastolic blood pressure across the childbearing period than those with all term deliveries (1.59 versus −0.73 mm Hg, P<0.01); the rates of change did not differ by group, both prechildbearing and postchildbearing. Women with preterm deliveries had a larger body mass index increase across the childbearing period (1.66 versus 1.22 kg/m², P=0.03) compared with those with all term deliveries, followed by a steeper increase after the childbearing period (0.22 versus 0.17 kg/m² per year, P=0.02).

Conclusions

Preterm delivery was associated with unfavorable patterns of change in diastolic blood pressure and adiposity that originate during the childbearing years and persist or exacerbate later in life. These adverse changes may contribute to the elevated cardiovascular risk among women with preterm delivery.

Using social cognitive theory to explain physical activity in Iranian women preparing for pregnancy

Despite the known useful effects of regular physical activity during the preconception period on pregnancy outcomes, sedentary lifestyle is a prevalent phenomenon in reproductive-aged women. Using social cognitive theory (SCT) as its theoretical framework, the aim of this study was to explain physical activity model in the women preparing for pregnancy in Isfahan, Iran. This cross-sectional study was conducted on 220 Iranian women undergoing preconception care. The SCT constructs were measured using a researcher-made questionnaire. The duration of physical activity with moderate/severe intensity was also measured using the long form of the International Physical Activity Questionnaire. The data were analyzed using Spearman correlation coefficient and multivariable linear regression. The theoretical model was tested using structural equation modeling. The results showed that observational learning (β =.65, p <.0001) was the most important determinant of the physical activity level. The default model provided an adequate to good fit to the data (CMIN/DF = 2.10, p =.097). The results of the present study emphasized the role of observational learning in forming physical activity behavior in pre-pregnancy period; therefore, the design of interventions for providing the opportunity of observational learning may improve the level of physical activity among the women preparing for pregnancy.

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.

The relationship between total cholesterol and postpartum impaired glucose tolerance in women with gestational diabetes mellitus

Background

History of gestational diabetes mellitus (GDM) and serum lipid abnormalities were associated with postpartum impaired glucose tolerance. To investigate the association between concentration of total cholesterol (TC), at the time of GDM diagnosis, and risk of postpartum glucose intolerance.

Methods

Women who were diagnosed GDM with a live singleton delivery between January 1, 2013 and December 31, 2017 were included. Women were grouped based on the TC quartiles at the time of GDM diagnosis and had an OGTT at 6–12 weeks after delivery. The relationship between TC and the risk of postpartum glucose intolerance was assessed by COX regression.

Results

A total of 845 women were in the final analysis. Higher TC quartile at diagnosis of GDM was associated with a decreased risk of postpartum glucose intolerance. Women in the highest TC quartile (>7.0 mmol L^− 1) had approximately only half-risk of any postpartum glucose intolerance, compared with women in the lowest TC quartile (<5.5 mmol L^− 1).

Conclusions

The decreased concentration of TC, at the time of GDM diagnosis, was related to an increased risk of postpartum abnormal glucose regulation in GDM women. Therefore, because both excessively increased and decreased TC were associated with pregnancy and postpartum complications, the optimal concentration of maternal TC throughout pregnancy remained to be further researched.

Maternal cardiovascular disease risk factors as predictors of preterm birth in California: a case-control study

OBJECTIVE

To determine whether maternal cardiovascular disease (CVD) risk factors predict preterm birth.

DESIGN

Case control.

SETTING

California hospitals.

PARTICIPANTS

868 mothers with linked demographic information and biospecimens who delivered singleton births from July 2009 to December 2010.

METHODS

Logistic regression analysis was employed to calculate odds ratios for the associations between maternal CVD risk factors before and during pregnancy (including diabetes, hypertensive disorders and cholesterol levels) and preterm birth outcomes.

PRIMARY OUTCOME

Preterm delivery status.

RESULTS

Adjusting for the other maternal CVD risk factors of interest, all categories of hypertension led to increased odds of preterm birth, with the strongest magnitude observed in the pre-eclampsia group (adjusted OR (aOR), 13.49; 95% CI 6.01 to 30.27 for preterm birth; aOR, 10.62; 95% CI 4.58 to 24.60 for late preterm birth; aOR, 17.98; 95% CI 7.55 to 42.82 for early preterm birth) and chronic hypertension alone for early preterm birth (aOR, 4.58; 95% CI 1.40 to 15.05). Diabetes (types 1 and 2 and gestational) was also associated with threefold increased risk for preterm birth (aOR, 3.06; 95% CI 1.12 to 8.41). A significant and linear dose response was found between total and low-density lipoprotein (LDL) cholesterol and aORs for late and early preterm birth, with increasing cholesterol values associated with increased risk (likelihood χ² differences of 8.422 and 8.019 for total cholesterol for late and early, and 9.169 and 10.896 for LDL for late and early, respectively). Receiver operating characteristic curves using these risk factors to predict late and early preterm birth produced C statistics of 0.601 and 0.686.

CONCLUSION

Traditional CVD risk factors are significantly associated with an increased risk of preterm birth; these findings reinforce the clinical importance of integrating obstetric and cardiovascular risk assessment across the healthcare continuum in women.

The Preconception Period analysis of Risks and Exposures Influencing health and Development (PrePARED) consortium

BACKGROUND

Preconception health may have intergenerational influences. We have formed the PrePARED (Preconception Period Analysis of Risks and Exposures influencing health and Development) research consortium to address methodological, conceptual, and generalisability gaps in the literature.

OBJECTIVES

The consortium will investigate the effects of preconception exposures on four sets of outcomes: (1) fertility and miscarriage; (2) pregnancy-related conditions; (3) perinatal and child health; and (4) adult health outcomes.

POPULATION

A study is eligible if it has data measured for at least one preconception time point, has a minimum of selected core data, and is open to collaboration and data harmonisation.

DESIGN

The included studies are a mix of studies following women or couples intending to conceive, general-health cohorts that cover the reproductive years, and pregnancy/child cohort studies that have been linked with preconception data. The majority of the participating studies are prospective cohorts, but a few are clinical trials or record linkages.

METHODS

Data analysis will begin with harmonisation of data collected across cohorts. Initial areas of interest include nutrition and obesity; tobacco, marijuana, and other substance use; and cardiovascular risk factors.

PRELIMINARY RESULTS

Twenty-three cohorts with data on almost 200 000 women have combined to form this consortium, begun in 2018. Twelve studies are of women or couples actively planning pregnancy, and six are general-population cohorts that cover the reproductive years; the remainder have some other design. The primary focus for four was cardiovascular health, eight was fertility, one was environmental exposures, three was child health, and the remainder general women's health. Among other cohorts assessed for inclusion, the most common reason for ineligibility was lack of prospectively collected preconception data.

CONCLUSIONS

The consortium will serve as a resource for research in many subject areas related to preconception health, with implications for science, practice, and policy.

Association of preterm birth with lipid disorders in early adulthood: A Swedish cohort study

BACKGROUND

Preterm birth has previously been linked with cardiovascular disease (CVD) in adulthood. However, associations with lipid disorders (e.g., high cholesterol or triglycerides), which are major risk factors for CVD, have seldom been examined and are conflicting. Clinicians will increasingly encounter adult survivors of preterm birth and will need to understand the long-term health sequelae. We conducted the first large population-based study to determine whether preterm birth is associated with an increased risk of lipid disorders.

METHODS AND FINDINGS

A retrospective national cohort study was conducted of all 2,235,012 persons born as singletons in Sweden during 1973 to 1995 (48.6% women), who were followed up for lipid disorders identified from nationwide inpatient, outpatient, and pharmacy data through 2016 (maximum age 44 years). Cox regression was used to adjust for other perinatal and maternal factors, and co-sibling analyses assessed the potential influence of unmeasured shared familial (genetic and/or environmental) factors. A total of 25,050 (1.1%) persons were identified with lipid disorders in 30.3 million person-years of follow-up. Each additional 5 weeks of gestation were associated with a 14% reduction in risk of lipid disorders (adjusted hazard ratio [HR], 0.86; 95% CI, 0.83-0.89; P < 0.001). Relative to full-term birth (gestational age 39-41 weeks), the adjusted HR associated with preterm birth (<37 weeks) was 1.23 (95% CI, 1.16-1.29; P < 0.001), and further stratified was 2.00 (1.41-2.85; P < 0.001) for extremely preterm (22-27 weeks), 1.33 (1.19-1.49; P < 0.001) for very preterm (28-33 weeks), and 1.19 (1.12-1.26; P < 0.001) for late preterm (34-36 weeks). These findings were similar in men and women (e.g., preterm versus full-term, men: HR, 1.22; 95% CI, 1.14-1.31; P < 0.001; women: HR, 1.23; 1.12-1.32; P < 0.001). Co-sibling analyses suggested that they were substantially though not completely explained by shared genetic or environmental factors in families. The main study limitation was the unavailability of laboratory data to assess specific types or severity of lipid disorders.

CONCLUSIONS

In this large national cohort, preterm birth was associated with an increased risk of lipid disorders in early- to midadulthood. Persons born prematurely may need early preventive evaluation and long-term monitoring for lipid disorders to reduce their future cardiovascular risks.

Differences in Pregnancy Metabolic Profiles and Their Determinants between White European and South Asian Women: Findings from the Born in Bradford Cohort

There is widespread metabolic disruption in women upon becoming pregnant. South Asians (SA) compared to White Europeans (WE) have more fat mass and are more insulin-resistant at a given body mass index (BMI). Whether these are reflected in other gestational metabolomic differences is unclear. Our aim was to compare gestational metabolic profiles and their determinants between WE and SA women. We used data from a United Kingdom (UK) cohort to compare metabolic profiles and associations of maternal age, education, parity, height, BMI, tricep skinfold thickness, gestational diabetes (GD), pre-eclampsia, and gestational hypertension with 156 metabolic measurements in WE (n = 4072) and SA (n = 4702) women. Metabolic profiles, measured in fasting serum taken between 26–28 weeks gestation, were quantified by nuclear magnetic resonance. Distributions of most metabolic measures differed by ethnicity. WE women had higher levels of most lipoprotein subclasses, cholesterol, glycerides and phospholipids, monosaturated fatty acids, and creatinine but lower levels of glucose, linoleic acid, omega-6 and polyunsaturated fatty acids, and most amino acids. Higher BMI and having GD were associated with higher levels of several lipoprotein subclasses, triglycerides, and other metabolites, mostly with stronger associations in WEs. We have shown differences in gestational metabolic profiles between WE and SA women and demonstrated that associations of exposures with these metabolites differ by ethnicity.

Maternal lipid profiles vs. fetal growth and cord blood hematopoietic cells: weak associations in healthy Korean newborn-mother pairs

BACKGROUND

We aimed to define the maternal lipid profiles that are associated with fetal growth and cord blood (CB) hematopoietic cells in healthy Korean full-term newborns.

METHODS

A total of 608 fetal-maternal pairs were enrolled; mothers voluntarily donated CB with informed consent. We analyzed birth weight (BW) as a marker of fetal growth, and we examined total nucleated cells (TNCs) and CD34⁺ cell concentrations of CB as markers of hematopoietic progenitor cell (HPC) contents. We also analyzed maternal lipid levels and investigated their associations with BW, TNCs and CD34⁺ cells.

RESULTS

Maternal triglycerides (TG) showed a significant positive association with BW and CD34⁺ cells, and low-density lipoprotein (LDL) showed a negative association with BW and CD34⁺ cells. Though not statistically significant, higher maternal TG showed a tendency toward higher levels of TNCs. Maternal TG was independently and positively correlated with BW, and maternal LDL was independently and negatively correlated with CD34⁺ cells, although the impacts were not as strong, as indicated by small beta coefficients (0.157 and -0.226, respectively).

CONCLUSIONS

We were able to investigate the association of maternal lipid profiles with BW and CB HPCs in healthy Korean newborn-mother pairs in this study. Both BW and the HPC contents showed independent associations with maternal TG and LDL, although the effect of maternal lipid levels on fetal growth and HPCs was not strong in the normal healthy population. Because maternal lipid levels were assessed once in the healthy fetal-maternal pairs, we could not investigate those associations across pregnancy.

The Association between Dyslipidemia and Preterm Birth: A Prospective Cohort Study in The North of Iran

BACKGROUND

Dyslipidemia is recognized as an important factor in the incidence of Preterm Birth (PTB). The early diagnosis of factors affecting PTB is important in the reduction of maternalneonatal complications; therefore, we aimed to evaluate the association between dyslipidemia and PTB in women from the Guilan province of Iran.

METHODS

The current investigation was a prospective cohort study on 378 pregnant women in Rasht city (Guilan province), during 2018-2019. Samples were randomly selected among pregnant women who referred to Al-Zahra hospital. Association of the lipid profiles: Total Cholesterol (TC), High- Density Lipoprotein (HDLC), Low-Density Lipoprotein (LDLC), and Triglycerides (TG) with PTB was assessed using the Chi-square, Fisher tests and logistic regression analysis.

RESULTS

Our findings showed that of the evaluated lipid profiles, TG and TC had the highest predictive power with AUC =0.833 (95٪, CI: 0.736-0.930) and 0.772 (95%, CI: 0.676-0.867), respectively; also, their sensitivity and specificity were 83.3%, 70.2% and 83.3%, 66.1%, respectively. Moreover, abnormal LDL concentrations increase the risk of PTB by two folds (P < 0.05).

CONCLUSION

It seems that by controlling the lipid profiles of pregnant women, the risk of PTB could be reduced.

Placental secretion of apolipoprotein A1 and E: the anti-atherogenic impact of the placenta

High levels of atherogenic lipids in pregnancy are associated with health complications for the mother, the fetus and the newborn. As endocrine secretory tissue, the human placenta releases apolipoproteins (apos), particularly apoA1 and apoE. However, the magnitude and the directionality of the apo secretions remain unknown. We aimed to 1) determine the amount and orientation (apical-maternal versus basal-fetal) of placentally secreted apoA1 and apoE using human perfused placenta and primary trophoblast cell (PTC) culture, 2) compare apoA1 and apoE secretions of PTC with that of hepatocytes and 3) associate the obtained results with human blood levels by determining apoA1 and apoE concentrations in maternal and fetal serum samples. In perfused placenta and serum samples, apoA1 and apoE concentrations were significantly higher at the maternal compared to the fetal side. For apoE a similar trend was found in PTC. For apoA1, the secretion to the apical side declined over time while release to the basal side was stable resulting in significantly different apoA1 concentrations between both sides. Unexpectedly, PTC secreted significantly higher amounts of apoA1 and apoE compared to hepatocytes. Our data indicate that the placenta may play an important role in maternal and fetal cholesterol homeostasis via secretion of anti-atherogenic apos.

Physical activity for healthy pregnancy among Iranian women: Perception of facilities versus perceived barriers

BACKGROUND

Regular physical activity during preconception period has beneficial effects on the health of women during conception and the identification of factors associated with it is an effective factor for improving the behavior. Therefore, the aim of this study is to evaluate the relationship between the physical activity and health belief model (HBM) constructs (perceived susceptibility/severity, barriers, and self-efficacy) as intrapersonal factors among women undergoing preconception care.

METHODS

In this cross-sectional study, 110 women who were undergoing preconception care were carried out. Moreover, health belief constructs and attitude toward physical activity were assessed through the use of researcher-made questionnaire. In addition, the duration of physical activity with moderate/vigorous intensity was evaluated utilizing a long form of the International Physical Activity Questionnaire.

RESULTS

The results showed that although there was a relationship between the all health belief constructs and attitude toward physical activity and the duration of leisure physical activities carried out during (P < 0.05), but using the linear regression test showed that only perceived barriers, independent from other variables, had a significant inverse correlation with this type of activities (β = -0.27, P = 0.02).

CONCLUSION

The findings of this study showed that among the constructs of theHBM, perceived barriers are the most important predictor of physical activity in women during the preconception period and emphasize the need to design possible means to promote physical activity to remove barriers to effective physical activity.

Pre-pregnancy cardiovascular risk factors and racial disparities in birth outcomes: the Bogalusa Heart Study

BACKGROUND

Racial disparities in birth outcomes are mirrored in cardiovascular health. Recently there have been calls for more attention to preconception and interconceptional health in order to improve birth outcomes, including as a strategy to reduce black-white disparities.

METHODS

As part of a larger study of cardiovascular and reproductive health ("Bogalusa Babies"), female participants were linked to their children's birth certificates for Louisiana, Mississippi, and Texas births from 1982 to 2009. Three thousand and ninety-five women were linked to birth certificate data. Birth outcomes were defined as low birthweight (LBW) birthweight < 2500 g; preterm birth (PTB), > 3 weeks early; small for gestational age (SGA), <10th percentile for gestational age (percentiles based on study population); large for gestational age (LGA) >90th percentile for gestational age]. Cardiovascular measures (blood pressure, lipids, glucose, insulin) at the visit closest in time but prior to the pregnancy was examined as predictors of birth outcomes using logistic models adjusted for covariates.

RESULTS

Only a few cardiovascular risk factors were associated with birth outcomes. Triglycerides were associated with higher risk of LBW among whites (aOR 1.05, 95% 1.01-1.10). Higher glucose was associated with a reduction in risk of SGA for black women (aOR 0.85, 95% CI 0.76-0.95), but not whites (p for interaction = 0.02). Clear racial disparities were found, but they were reduced modestly (LBW/SGA) or not at all (PTB/LGA) after CVD risk factors were adjusted for.

CONCLUSIONS

This analysis does not provide evidence for preconception cardiovascular risk being a strong contributor to racial disparities.

Cardiorespiratory fitness, exercise haemodynamics and birth outcomes: the Coronary Artery Risk Development in Young Adults Study

OBJECTIVE

Determine associations of cardiorespiratory fitness, exercise systolic blood pressure (SBP) and heart rate recovery (HRR) following a maximal exercise test performed years preceding pregnancy with odds of preterm birth (PTB; <37 weeks' gestation) and small for gestational age (SGA; birthweight <10th percentile) delivery.

DESIGN

Prospective, longitudinal.

SETTING

Multi-site, observational cohort study initially consisting of 2787 black and white women aged 18-30 at baseline (1985-86) and followed for 25 years (Y25; 2010-2011).

POPULATION

768 nulliparous women at baseline who reported ≥1 live birth by the Y25 exam.

METHODS

We used Poisson regression to determine associations of exposures with PTB/SGA.

MAIN OUTCOME MEASURES

PTB and/or SGA births.

RESULTS

Women with PTB (n = 143) and/or SGA (n = 88) were younger, had completed fewer years of education and were more likely to be black versus women without PTB/SGA (n = 546). Women with PTB/SGA had lower fitness (501 ± 9 versus 535 ± 6 seconds, P < 0.002) and higher submaximal SBP than women without PTB/SGA (144 ± 1 versus 142 ± 1 mmHg, P < 0.04). After adjustment, no exercise test variables were associated with PTB/SGA, though the association with HRR and submaximal SBP approached significance in the subset of women who completed the exercise test <5 years before the index birth.

CONCLUSIONS

Neither fitness nor haemodynamic responses to exercise a median of 5 years preceding pregnancy, were associated with PTB/SGA. These findings indicate excess likelihood of PTB/SGA is not detectable by low fitness or exercise haemodynamic responses 5 years preceding pregnancy, but exercise testing, especially HRR and submaximal SBP, may be more useful when conducted closer to the onset of pregnancy.

TWEETABLE ABSTRACT

Exercise testing conducted >5 years before pregnancy may not detect women likely to have PTB/SGA.

Preconceptional Cardiovascular Health and Pregnancy Outcomes in Women with Systemic Lupus Erythematosus

OBJECTIVE

To estimate the effects of preconceptional cardiovascular (CV) health, measured by American Heart Association (AHA) guidelines, on pregnancy outcomes in women with systemic lupus erythematosus (SLE).

METHODS

The study included patients in the Hopkins Lupus Pregnancy Cohort. Body mass index (BMI), total cholesterol, and blood pressure (BP) in the most recent clinic visit prior to conception or first trimester were used to determine CV health (ideal, intermediate, or poor health) based on AHA definitions. Outcomes included preterm birth, gestational age at birth, and small for gestational age (SGA). Multivariable linear and logistic regression models with generalized estimating equations estimated the association of each CV health factor and outcome.

RESULTS

The analysis included 309 live births. There were 95 preterm births (31%), and of the 293 pregnancies with birth weights, 18% were SGA. Ideal BMI, total cholesterol, and BP were reported in 56%, 85%, and 51% of pregnancies, respectively. Intermediate BMI was associated with decreased odds of SGA (OR 0.26, 95% CI 0.11-0.63), adjusted for race and prednisone use. Intermediate/poor total cholesterol was associated with increased odds of preterm birth (OR 2.21, 95% CI 1.06-4.62). Intermediate/poor BP was associated with decreased gestational age at birth (β -0.96, 95% CI -1.62 to -0.29).

CONCLUSION

Poor/intermediate preconception CV health affects pregnancy outcomes of preterm birth and SGA infants among women with SLE. Efforts to maintain BMI, total cholesterol, and BP within the recommended ideal range prior to pregnancy is important to improve pregnancy outcomes in women with SLE.

Lipoprotein particle concentration measured by nuclear magnetic resonance spectroscopy is associated with gestational age at delivery: a prospective cohort study

OBJECTIVE

To estimate the association between lipoprotein particle concentrations in pregnancy and gestational age at delivery.

DESIGN

Prospective cohort study.

SETTING

The study was conducted in the USA at the University of North Carolina.

POPULATION

We assessed 715 women enrolled in the Pregnancy, Infection, and Nutrition study from 2001 to 2005.

METHODS

Fasting blood was collected at two time points (<20 and 24-29 weeks of gestation). Nuclear magnetic resonance (NMR) quantified lipoprotein particle concentrations [low-density lipoprotein (LDL), high-density lipoprotein (HDL), very-low density lipoprotein (VLDL)] and 10 subclasses of lipoproteins. Concentrations were assessed as continuous measures, with the exception of medium HDL which was classified as any or no detectable level, given its distribution. Cox proportional hazards models estimated hazard ratios (HR) for gestational age at delivery adjusting for covariates.

MAIN OUTCOME MEASURES

Gestational age at delivery, preterm birth (<37 weeks of gestation), and spontaneous preterm birth.

RESULTS

At <20 weeks of gestation, three lipoproteins were associated with later gestational ages at delivery [large LDL_NMR (HR 0.78, 95% CI 0.64-0.96), total VLDL_NMR (HR 0.77, 95% CI 0.61-0.98), and small VLDL_NMR (HR 0.78, 95% CI 0.62-0.98], whereas large VLDL_NMR (HR 1.19, 95% CI 1.01-1.41) was associated with a greater hazard of earlier delivery. At 24-28 weeks of gestation, average VLDL_NMR (HR 1.25, 95% CI 1.03-1.51) and a detectable level of medium HDL_NMR (HR 1.90, 95% CI 1.19-3.02) were associated with earlier gestational ages at delivery.

CONCLUSION

In this sample of pregnant women, particle concentrations of VLDL_NMR , LDL_NMR , IDL_NMR , and HDL_NMR were each independently associated with gestational age at delivery for all deliveries or spontaneous deliveries <37 weeks of gestation. These findings may help formulate hypotheses for future studies of the complex relationship between maternal lipoproteins and preterm birth.

TWEETABLE ABSTRACT

Nuclear magnetic resonance spectroscopy may identify lipoprotein particles associated with preterm delivery.

Pre-pregnancy endothelial dysfunction and birth outcomes: The Coronary Artery Risk Development in Young Adults (CARDIA) Study

Endothelial dysfunction is a form of subclinical cardiovascular disease that may be involved in preterm birth and small-for-gestational-age deliveries. However, concentrations of biomarkers of endothelial dysfunction before pregnancy have rarely been measured. We hypothesized that higher levels of biomarkers of endothelial dysfunction (cellular adhesion molecules and selectins) would be associated with odds of preterm birth and/or small-for-gestational-age deliveries. We included 235 women from the Coronary Artery Risk Development in Young Adults (CARDIA) study who were nulliparous at Y7, reported ≥1 live birth through Y25, and had ≥1 biomarker measured at Y7. We tested for associations between individual biomarkers and an averaged z-score representing total endothelial dysfunction with preterm birth and/or small-for-gestational-age deliveries using Poisson regression, adjusted for demographic and clinical characteristics at the exam immediately preceding index birth. At Y7, total evidence of  endothelial dysfunction was similar in women who did (n = 59) and did not have (n = 176) preterm birth and/or small-for-gestational-age deliveries. There was no association between biomarkers of endothelial dysfunction (either individual biomarker or total score) with odds of preterm birth and/or small-for-gestational-age deliveries after adjustment: IRR = 1.01, 95% CI: 0.74, 1.39, p = 0.93 for total endothelial biomarker score. Associations were not modified by race. We conclude that biomarkers of endothelial dysfunction in nulliparous women, measured ~3 years before pregnancy, did not identify women at risk for preterm birth and/or small-for-gestational-age deliveries. This suggests that the maternal endothelial dysfunction that is believed to contribute to these birth outcomes may not be detectable before pregnancy.

Association of Spontaneous Preterm Delivery and Future Maternal Cardiovascular Disease

Cardiovascular disease (CVD) risk factors are well established. However, little is known about a woman's cardiovascular response to pregnancy, which appears to be an early marker of future maternal CVD risk. Spontaneous preterm delivery (sPTD) has been associated with a ≤3-fold increased risk of maternal CVD death later in life compared with having a term delivery. This review focuses on 3 key areas to critically assess the association of sPTD and future maternal CVD risk: (1) CVD risk factors, (2) inflammatory biomarkers of interest, and (3) specific forms of vascular dysfunction, such as endothelial function and arterial stiffness, and mechanisms by which each may be linked to sPTD. The association of sPTD with subsequent future maternal CVD risk suggests that a woman's abnormal response to pregnancy may serve as her first physiological stress test. These findings suggest that future research is needed to understand why women with sPTD may be at risk for CVD to implement effective interventions earlier in a woman's life.

Cardiovascular biochemical risk factors among women with spontaneous preterm delivery

OBJECTIVE

To determine whether women delivering preterm have unfavorable cardiovascular profiles as compared with women who deliver at term.

METHODS

A prospective observational cohort study enrolled 165 women with spontaneous preterm delivery (sPTD) at 24⁺⁰ and 36⁺⁶ gestational weeks in three perinatal care centers in The Netherlands between August 2012 and August 2014. Total cholesterol, triglycerides, high-density lipoprotein (HDL)-cholesterol, low-density lipoprotein (LDL)-cholesterol, apolipoprotein, glucose, and homocysteine were measured within 24 hours after delivery. Lipids and cardiovascular biochemical risk factors were compared between women with sPTD and an external comparison group of 30 women with term delivery via analysis of covariance.

RESULTS

Mean gestational age at delivery was 30.7 ± 3.6 weeks in the sPTD group and 40.3 ± 1.3 weeks in the reference group. Data were adjusted for body mass index, age, and center. As compared with the reference group, total cholesterol and LDL-cholesterol levels were lower and glucose levels were higher among women with sPTD.

CONCLUSION

An association between sPTD and unfavorable lipids and cardiovascular biochemical risk factors was not established. The higher levels of glucose in the sPTD group might be due to increased insulin resistance, which is associated with a higher risk of sPTD.

Lipoprotein Heterogeneity Early in Pregnancy and Preterm Birth

Background

The concentration and size of lipoprotein particles are associated with race, inflammation and disease. When triglycerides are high, as in pregnancy, lipoprotein particle size may have physiologic importance beyond conventional lipid measurements. We considered that lipoprotein particles may be related to preterm birth (PTB), and explored race differences.

Methods

Samples were collected at 9 weeks gestation (22 PTB [<37 weeks]; 42 term births [≥37 weeks]). Lipids were assayed using standard techniques. Concentrations of high-density lipoprotein, low-density lipoprotein, very low-density lipoprotein particles (HDL-P, LDL-P, and VLDL-P) and markers of systemic inflammation were quantified using NMR spectroscopy and related to PTB.

Results

Women with PTB had lower VLDL-P (−10.66 nmol/L, p=0.03) and higher systemic inflammation (+19.2 μmol/L, p=0.02) compared to women with term births, independent of race, pre-pregnancy BMI and smoking. Black vs. White women had lower VLDL-P and higher HDL-cholesterol (both p<0.05). Race-specific results indicated that large HDL-P and inflammation (GlycB) were higher with PTB vs. term birth among black women only.

Conclusion

Women with PTB had lower VLDL-P early in pregnancy, which may represent impaired lipid response. Black-White differences in the lipoprotein profile are similar to non-pregnant adults, but race-specific lipoprotein and inflammation associations with PTB warrant further study.

Placental ABCA1 Expression Is Increased in Spontaneous Preterm Deliveries Compared with Iatrogenic Preterm Deliveries and Term Deliveries

Objective

Abnormal expression of ABCA1 and ABCG1 in the placenta can elicit lipid metabolism disorder and adverse pregnancy outcomes. However, whether it is associated with preterm delivery remains unclear. Our present study aimed to evaluate the relationship between abnormal expression of ABCA1 or ABCG1 and preterm delivery.

Methods

Maternal blood and placental tissues from women with spontaneous deliveries (SPD), iatrogenic deliveries (IPD), and term deliveries (TD) were collected. The lipid content and expression of ABCA1 and ABCG1 were subsequently measured.

Results

Compared with IPD and TD groups, the HDL, TD, LDL, and TC levels were lower in the maternal blood but higher (except TC) in the cord blood of the SPD group. The extracellular lipid content in the placentas of the SPD group was also notably lower relative to the IPD and TD groups. Moreover, the protein and mRNA expressions of ABCA1 in the placentas of the SPD group were significantly higher compared with the IPD and TD groups; however, there was no obvious difference among the three groups in the protein and mRNA expressions of ABCG1.

Conclusions

Abnormal expression of ABCA1 may be associated with the dysregulation of placental lipid metabolism and the occurrence or development of SPD.

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

BACKGROUND

It is unknown whether an unfavorable (atherogenic) lipid profile and homocysteine level, which could supersede clinical cardiovascular disease, is also associated with an increased risk of spontaneous preterm delivery (sPTD). A systematic review of studies assessing the lipid profile and homocysteine value of women with sPTD compared to women with term delivery in pre-pregnancy and during pregnancy.

METHODS

A systematic search of peer-reviewed articles published between January 1980 and May 2014 was performed using MEDLINE, EMBASE and the Cochrane database. We included case-control and cohort studies that examined triglycerides, high/low density lipoprotein cholesterol, total cholesterol and homocysteine in women with sPTD. Articles were subdivided in pre-pregnancy, first, second and third trimester. Of 708 articles reviewed for eligibility, 14 met our inclusion criteria.

RESULTS AND CONCLUSION

Nine cohort studies and five case-control studies were analyzed, reporting on 1466 cases with sPTD and 11296 controls with term delivery. The studies suggest a possible elevated risk of sPTD in woman with high TG levels, no association of high and low density lipoprotein cholesterol with the risk of sPTD was found. High homocysteine levels are associated with sPTD in the second trimester. The role of triglycerides and homocysteine in sPTD should be explored further.

Multigenerational Cardiometabolic Risk as a Predictor of Birth Outcomes: The Bogalusa Heart Study

OBJECTIVE

To examine the relationship between generation 1 (grandmaternal) cardiometabolic risk factors and generation 3 (grandchild's) birthweight and gestational age.

STUDY DESIGN

Mother-daughter pairs in the Bogalusa Heart Study (1973-present) were linked to their children's birth certificates; women were also interviewed about their reproductive histories, creating a 3-generation linkage including 177 generation 1 (grandmothers), 210 generation 2 (mothers), and 424 generation 3 (children). Prepregnancy cardiometabolic risk factors (body mass index [BMI], lipids, glucose) or generation 1 (mean age 16.2 years) and 2 (mean age 11.1 years) were examined as predictors of generation 3 birthweight and gestational age using linear and logistic regression with adjustment for age, race, parity, and other confounders.

RESULTS

Generation 2 higher BMI was associated with higher birthweight (28 g per 1 unit, 95% CI 12-44) and gestational age (0.08 weeks, 95% CI 0.02-0.14) in generation 3, and generation 1 higher BMI was associated with higher birthweight (52 g, 95% CI 34-70) in the generation 2. Generation 1's higher glucose levels were associated with higher birthweight in generation 3 (adjusted beta 111 g, 95% CI 33-189), and triglycerides (adjusted beta -21, 95% CI -43-0) and low-density lipoprotein (adjusted beta -24, 95% CI -48-0) were associated with lower birthweight.

CONCLUSIONS

These results suggest the possibility of multigenerational developmental programming of birth outcomes, although mechanisms (whether biological or environmental) are undetermined.

Maternal Circulating Lipid Profile during Early Pregnancy: Racial/Ethnic Differences and Association with Spontaneous Preterm Delivery

Prior reports on the association between altered maternal serum lipid levels with preterm delivery are inconsistent. Ethnic differences in serum lipids during pregnancy and their relation to preterm delivery have not been studied. We examined the relationships of six maternal lipids during early pregnancy with the risk of spontaneous preterm delivery (SPTD). The design represents a case-control study nested within a large prospective, multiethnic cohort of young, generally healthy pregnant women. SPTD cases (n = 183) and controls who delivered at term (n = 376) were included. SPTD is defined as delivery at <37 completed weeks of gestation without indicated conditions. We found that African-American women had significantly increased levels of high-density lipoprotein cholesterol (HDL-C) and apolipoprotein A1 (apoA1), and lower triglyceride (TG) and apolipoprotein B (apoB) levels compared to Hispanic and non-Hispanic Caucasians combined. Elevated HDL-C and apoA1 concentrations were significantly associated with an increased odds of SPTD after controlling for potential confounding factors. The adjusted odds ratio (AOR) was 1.91 (95% confidence interval (CI) 1.15, 3.20) for the highest quartile of HDL-C relative to the lowest quartile, and for apoA1 the AOR was 1.94 (95% CI 1.16, 3.24). When controlling for ethnicity, the results remained comparable. These data suggest that pregnant African-American women had a more favorable lipid profile suggestive of a reduction in cardiovascular risk. Despite this, increased HDL-C and apoA1 were both found to be associated with SPTD.

Maternal plasma cholesterol and duration of pregnancy: A prospective cohort study in Ghana

Low plasma cholesterol may be associated with preterm birth; however, results are mixed and limited primarily to high-income countries. Our objective was to determine whether maternal plasma lipid concentrations are associated with pregnancy duration. We performed a nested cohort (n = 320) study of pregnant Ghanaian women enrolled in a randomized controlled trial. Total cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol, and triglyceride concentrations were analyzed in plasma at ≤20and 36 weeks gestation as continuous variables and also categorized into low, referent, or high (<10th, 10th-90th, >90th percentile). At ≤20 weeks, plasma lipid concentrations were not associated with pregnancy duration. At 36 weeks, total cholesterol and triglyceride concentrations were not associated with pregnancy duration. Higher HDL-C at 36 weeks was associated with a longer pregnancy duration (adjusted β-coefficient ± standard error: 0.05 ± 0.02 days mg^-1 /dL, p = .02); pregnancy duration was 5.9 ± 2.0 (mean ± standard error) days shorter among women with low HDL-C compared with the referent group (10th-90th percentile) (p = .02) and 8.6 ± 2.6 days shorter when compared with the high HDL-C group (p = .003). Pregnancy duration was 4.9 ± 2.1 days longer among women with low low-density lipoprotein cholesterol at 36 weeks gestation when compared with the referent group (p = .051). Our data suggest that low HDL-C in the third trimester of pregnancy is associated with a shorter duration of pregnancy in this study population but do not support the hypothesis that low total cholesterol is associated with a shorter pregnancy duration.

Childhood Risk Factors and Pregnancy-Induced Hypertension: The Bogalusa Heart Study

BACKGROUND

Pregnancy-induced hypertension (PIH) causes increased risk of maternal, fetal, and neonatal morbidity and mortality. Identification of risk factors for PIH in early life is central to the development of prevention strategies.

METHODS

A cohort of 703 women aged 25.5-51.3 years from the Bogalusa Heart Study were included. PIH were defined as self-reported hypertension during pregnancy and a blood pressure level <140/90mm Hg without antihypertensive medication (n = 131) at the subsequent examinations. Body mass index (BMI), systolic and diastolic blood pressure, high- and low-density lipoprotein cholesterol, and triglycerides measured during childhood (4-17 years) were considered. General linear models were used to examine differences in childhood between those who did and those who did not develop PIH. Logistic regression models were used to estimate odds ratios for PIH associated with childhood risk factors.

RESULTS

Compared to women who did not develop PIH, those who developed PIH had higher BMI (20.2 vs. 19.2kg/m(2), P = 0.0002) and systolic blood pressure (104.1 vs. 103.3mm Hg, P = 0.008) in childhood. After adjustment for other variables, childhood BMI was the only risk factor associated with PIH, with each standard deviation increase in childhood BMI being associated with an odds ratio of 1.35 (95% confidence interval: 1.08-1.68) for PIH. The odds of PIH increased significantly as childhood BMI increased from the bottom quartile to the top quartile (P for trend = 0.006).

CONCLUSIONS

Elevated childhood BMI is a significant risk factor for PIH in adulthood, which underscores the importance of body weight control in childhood for prevention of PIH.

[Relationship between lipid alterations during pregnancy and adverse pregnancy outcomes]

Lipids play an important role during pregnancy, and in this period major changes occur in lipoprotein metabolism. During the third trimester plasma cholesterol and triglyceride levels are substantially increased, returning to normal after delivery. Described associations between increased morbidity during pregnancy and excessive increases in plasma cholesterol and triglycerides. For this reason we have reviewed the relationship between lipid alterations, preeclampsia, gestational diabetes and preterm birth. The overall metabolic control can improve pregnancy outcomes, and the assessment of supraphysiological changes in lipid profile will classify pregnancy risk at a higher level, which would entail a stricter control.

Perinatal outcomes of singleton siblings: the effects of changing maternal fertility status

PURPOSE

The objective of this study was to evaluate the effect of changing fertility status on perinatal outcomes of singleton siblings, conceived with and without assisted reproductive technology (ART).

METHOD

A longitudinal cohort study of Massachusetts resident women having two consecutive singleton births during 2004-2010 was performed. Women were classified as ART (A), subfertile (S), or fertile (F) and categorized by their fertility status in each birth as A-A, A-S, S-A, S-S, F-A, F-S, and F-F. Within categories, adjusted mean birthweights, gestations, and birthweight Z scores were estimated with linear generalized estimating equations. Risks of low birthweight (LBW, <2500 g), preterm birth (PTB, <37 weeks), and placental complications were modeled using logistic regression by fertility status as adjusted odds ratios (AORs) and 95 % confidence intervals (CIs).

RESULTS

Birthweights in second pregnancies averaged 74-155 g higher, except for births to F-A women, who averaged -16 g lower. Most women had a reduction in length of gestation in their second pregnancies, with F-A women having the largest decline (-0.5 weeks). In first birth models, the risks for LBW and placental complications were increased for subfertile (AOR 1.39 [1.07-1.81] and 1.97 [1.33-2.93], respectively) and ART women (AOR 1.58 [1.29-1.93] and 3.40 [2.64-4.37], respectively). Second birth models showed increased risks for ART births of LBW (AOR 3.13 [2.19-4.48]) and placental complications (AOR 2.45 [1.56-3.86]) and greater risks of PTB for both ART (AOR 2.37 [1.74-3.23]) and subfertile women (AOR 1.47 [1.02-2.13]).

CONCLUSIONS

Declining fertility status, with and without assisted reproductive technology treatment, is associated with increasing risks for adverse outcomes, greatest for women whose fertility status declined the most.

Maternal apolipoprotein E genotype as a potential risk factor for poor birth outcomes: The Bogalusa Heart Study

OBJECTIVE

The objective of this study was to assess the association between apolipoprotein E (apoE) genotype and preterm birth (PTB) and small for gestational age (SGA).

STUDY DESIGN

ApoE phenotyping was performed on 680 women linked to 1065 births. Allele frequencies were compared and PTB and SGA risk was estimated using log-binomial regression.

RESULTS

The ɛ2 allele was more common in SGA births (P<0.01). SGA risk was increased among ɛ2 carriers compared with genotype ɛ3/ɛ3, though associations were attenuated following adjustment for maternal age, education, race, smoking and prenatal visits. Stronger associations were observed for term SGA (first birth: adjusted relative risk (aRR)=1.78, 95% confidence interval (CI) 1.06 to 2.98; any birth: aRR=1.52, 95% CI 0.96 to 2.40) and among whites specifically (first: aRR=2.88, 95% CI 1.45 to 5.69; any: aRR=2.75, 95% CI 1.46 to 5.22).

CONCLUSIONS

Associations between maternal apoE genotype and SGA may represent decreased fetal growth in women with lower circulating cholesterol levels.

Preterm birth and long-term maternal cardiovascular health

PURPOSE

To investigate whether preterm birth (PTB) is associated with greater cardiovascular disease (CVD) risk in a longitudinal cohort.

METHODS

We examined differences in systolic blood pressure (SBP), diastolic blood pressure, insulin resistance (Homeostatic model assessment of insulin resistance), total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein, triglycerides, C-reactive protein, and interleukin 6 at 3 years postpartum between women who delivered preterm (gestation <37 weeks; n = 54) versus term (≥37 weeks; n = 751) using multivariable linear regression. We also assessed relations with body mass index, weight change from prepregnancy, and waist circumference at 3 and 7 years postpartum.

RESULTS

Median age at enrollment was 33.9 years (range: 16.4-44.9). After adjusting for age, race, prepregnancy body mass index, parity, marital status, education, and SBP during early pregnancy, women with PTB had 3.99 mm Hg (95% confidence interval, 0.82-7.16) higher SBP and 7.01 mg/dL (1.54-12.50) lower HDL than those who delivered at term. The association with SBP was attenuated after accounting for hypertension before or during pregnancy (2.78 mm Hg [-0.30 to 5.87]). PTB was not related to other postpartum outcomes.

CONCLUSIONS

PTB is related to greater CVD risk by 3 years postpartum as indicated by higher SBP and lower HDL. Although these associations may be due to preexisting conditions exacerbated during pregnancy, PTB may flag high-risk women for more vigilant CVD monitoring and lifestyle interventions.

Prior preterm or small-for-gestational-age birth related to maternal metabolic syndrome

OBJECTIVE

To estimate whether women who deliver small babies due to preterm birth or growth restriction have excess risk for cardiovascular disease and diabetes later in life.

METHODS

Eight years after pregnancy, we estimated the prevalence of metabolic syndrome and its components in a cohort study of women with prior preterm (preterm birth before 37 weeks, n=181) or small for gestational age ([SGA], less than the tenth percentile, n=192) births, compared with women with term births (37 or more weeks, n=306). Women delivered at Magee-Womens Hospital in Pittsburgh, Pennsylvania, and those with preeclampsia or prepregnancy diabetes or hypertension were excluded. Women underwent a structured interview and fasting blood sampling.

RESULTS

Women were, on average, 8 years postpartum and 39 years old at evaluation. Women with a prior preterm birth had higher blood pressure, triglycerides, and LDL-cholesterol compared with those in a term control group. Women with prior SGA births were leaner and more likely to smoke compared with those with term births. Women with prior preterm birth had elevated risk of metabolic syndrome, adjusted for demographic, smoking and body size factors (23% preterm compared with 17% control group; odds ratio [OR] 1.76 [1.06, 2.80]). In women with a prior preterm birth, low HDL (11% preterm compared with 5% control group; OR 2.6 [1.2, 5.2]), hypertriglyceridemia (22% compared with 14%; OR 1.9 [1.2, 2.9]), and elevated glucose (24% compared with 19%; OR 1.5 [1.0, 2.3]) accounted for this excess metabolic syndrome. In women with SGA, the only element of metabolic syndrome that was aberrant was glucose metabolism.

CONCLUSION

Eight years after pregnancy, women with prior preterm or SGA births had evidence of metabolic syndrome compared with women with term births. Screening and intervention in these women after pregnancy may delay or prevent disease.

LEVEL OF EVIDENCE

: II.

Nonesterified fatty acids and spontaneous preterm birth: a factor analysis for identification of risk patterns

We considered that accumulation of nonesterified (free) fatty acids (NEFAs) in the first trimester of pregnancy would mark women at excess risk of spontaneous preterm birth (sPTB) and examined the interplay between NEFAs, lipids, and other markers to explore pathways to sPTB. In a case-control study nested in the Pregnancy Exposures and Preeclampsia Prevention Study (Pittsburgh, Pennsylvania, 1997-2001), we assayed NEFA levels in nonfasting serum collected at a mean gestational week of 9.4 (range, 4-20 weeks) in 115 women with sPTB (<37 weeks) and 222 women with births occurring at ≥37 weeks. C-reactive protein, total cholesterol, low-density lipoprotein and high-density lipoprotein (HDL) cholesterol, triglycerides, and uric acid were also measured. Polytomous logistic regression models were used to evaluate tertiles of NEFA levels and sPTB at <34 weeks and 34-36 weeks; factor analysis was used to characterize patterns of biomarkers. Women with NEFA levels in the highest tertile versus the lowest were 2.02 (95% confidence interval: 1.13, 3.48) times more likely to have sPTB, after adjustment for covariates. Risk of sPTB before 34 weeks was particularly high among women with high NEFA levels (odds ratio = 3.73, 95% confidence interval: 1.33, 10.44). Six biomarker patterns were identified, and 2 were associated with sPTB: 1) increasing NEFA and HDL cholesterol levels and 2) family history of gestational hypertension. NEFA levels early in pregnancy were independently associated with sPTB, particularly before 34 weeks. We also detected a novel risk pattern suggesting that NEFAs together with HDL cholesterol may be related to sPTB.

Trends in serum lipids and hypertension prevalence among non-pregnant reproductive-age women: United States National Health and Nutrition Examination Survey 1999-2008

Cardiovascular disease is one of the leading causes of death among reproductive-age women. In this study, we examine trends in the prevalence of dyslipidemia, hypertension, and related clinicians' advice among reproductive-age women. We conducted trend analysis of these factors among non-pregnant women aged 20-49 years (n = 5,768) using National Health and Nutrition Examination Survey (NHANES) data obtained between 1999 and 2008. Multiple linear regression and logistic regression analyses were used to examine linear trends over a 10-year period after adjusting for covariates. A downward trend was observed for the proportion of women with abnormal levels of low density lipoprotein (LDL; P = 0.038) and high density lipoprotein (HDL; P = 0.008) cholesterol from 1999 to 2008. In contrast, no significant changes were observed in the prevalence of abnormal total cholesterol (P = 0.948) and triglyceride levels (P = 0.300), or hypertension (P = 0.632). Based on the self-reported data, upward trends were observed in the rates of cholesterol checking (P = 0.002), high cholesterol (P = 0.012), receiving clinicians' advice to use lipid-lowering agents (P < 0.001) and patients' compliance with their advice (P < 0.001). Although rates of self-reported hypertension did not change over time (P = 0.120), receiving clinicians' advice to use antihypertensive medications (P = 0.003) and patients' compliance with these medications (P = 0.015) also increased significantly. Overall improvements in LDL and HDL cholesterol over this time period could be due to increases in related awareness, receiving advice to use medications, and patients' compliance with this advice. Use of antihypertensive medication has also increased among reproductive-age women in the US.