Maternal lipids at mid-pregnancy and the risk of preterm delivery

Dyslipidemia characterized by low density lipoprotein cholesterol and risk of preterm Birth: A Mendelian randomization study

BACKGROUND

Preterm birth is the leading cause of neonatal mortality worldwide, and dyslipidemia is associated with preterm birth in observational studies. We use Mendelian randomization (MR) analyses to uncover the causal association between blood lipid levels and preterm birth.

METHODS

We extracted uncorrelated (R2 < 0.001) single-nucleotide polymorphisms strongly associated (p < 5 × 10-8) with blood lipids from genome wide association studies of FinnGen database and UK Biobank participants. Inverse variance weighted method was the main MR analysis. Sensitivity analyses including genetic pleiotropy, heterogeneity, and directionality of causality were conducted.

RESULTS

The study included 115,082 participants with lipid measurements, 8,507 patients with preterm birth. Increasing apolipoprotein B (odds ratio (OR), 1.12[95 % CI, 1.02-1.23]; p = 0.019), low-density lipoprotein cholesterol (OR, 1.11[95 % CI, 1.00-1.22]; p = 0.040), non-high-density lipoprotein cholesterol (OR, 1.12[95 % CI, 1.01-1.24]; p = 0.026), remnant cholesterol (OR, 1.11[95 % CI, 1.00-1.23]; p = 0.047) and total free cholesterol (OR, 1.11[95 % CI, 1.01-1.23]; p = 0.037) were associated with increased risk of preterm delivery. Moreover, triglycerides in low-density lipoprotein were causally associated with the risk of PTB. Our sensitivity analysis yielded robust results, uncovering no evidence of horizontal pleiotropy or reverse causal relationships.

CONCLUSION

Our investigation unveils the adverse impact of dyslipidemia on preterm birth, with a particular emphasis on the detrimental effect of elevated low-density lipoprotein cholesterol.

Abnormal maternal apolipoprotein levels during pregnancy are risk factors for preterm birth in women with dichorionic twin pregnancies: A retrospective study

OBJECTIVE

In singleton-pregnant women, abnormal maternal apolipoprotein levels have been confirmed as a risk factor for preterm birth. However, there are currently no studies on the relationship of the related research in twin-pregnant women.

METHODS

This single-center retrospective study included 743 dichorionic twin-pregnant women who delivered between January 2019 and December 2020. Twins delivered before 37 weeks gestation were categorized as the preterm group, while those delivered at or after 37 weeks gestation were classified as the term group. Maternal serum apolipoprotein A1 (ApoA1) levels, apolipoprotein B (ApoB) levels, and the ApoB/ApoA1 ratio were measured in the first trimester(6-14 weeks), the second trimester(18-28 weeks) and the third trimester(after 28 weeks). We conducted SPSS analysis to evaluate the correlation between ApoA1 levels, ApoB levels, the ApoB/ApoA1 ratio and preterm birth.

RESULTS

Among the 743 included dichorionic twin-pregnant women, 53.57 % (398/743) delivered preterm. Compared with the term group, the ApoA1 levels in the third trimester were lower (p < 0.001), while the Apo B/ApoA1 ratio was higher in the second (p = 0.01) and third trimesters in the preterm group (p = 0.001). When preterm birth was categorized as iatrogenic and spontaneous preterm birth, the results were similar. In the analysis stratified by prepregnancy BMI, a higher risk of preterm birth was associated with low ApoA1 levels and a high Apo B/ApoA1 ratio in the second and third trimesters only among the subgroup of overweight/obese dichorionic twin-pregnant women.

CONCLUSIONS

Low ApoA1 levels and a high Apo B/ApoA1 ratio during the second and third trimesters were associated with a high incidence of preterm birth for overweight/obese dichorionic twin-pregnant women.

The association between dyslipidaemia in the first trimester and adverse pregnancy outcomes in pregnant women with subclinical hypothyroidism: a cohort study

BACKGROUND

Subclinical hypothyroidism (SCH) is linked to dyslipidaemia and adverse pregnancy outcomes. However, the impact of dyslipidaemia on the outcome of pregnancy in SCH is unclear.

METHODS

We enrolled 36,256 pregnant women and evaluated their pregnancy outcomes. The following data was gathered during the first trimester (≤ 13+ 6 weeks of gestation): total cholesterol (TC), low-density lipoprotein (LDL-C), triglyceride (TG), high-density lipoprotein (HDL-C), free thyroxine (FT4) and thyroid-stimulating hormone (TSH) concentrations. The reference ranges for lipids were estimated to range from the 5th to the 95th percentile. Logistic regression assessed the relationships between dyslipidaemia and adverse pregnancy outcomes, including abortion, preeclampsia/eclampsia, low birth weight, foetal growth restriction, premature rupture of foetal membranes, gestational hypertension, preterm birth, macrosomia and gestational diabetes mellitus (GDM). Additionally, the best thresholds for predicting adverse pregnancy outcomes based on TSH, FT4, and lipid levels were determined using receiver operating characteristic curves.

RESULTS

In the first trimester, LDL-C > 3.24 mmol/L, TG > 1.92 mmol/L, HDL-C < 1.06 mmol/L, and TC > 5.39 mmol/L were used to define dyslipidaemia. In this cohort, 952 (3.56%) patients were diagnosed with SCH, and those who had dyslipidaemia in the first trimester had higher incidences of gestational hypertension (6.59% vs. 3.25%), preeclampsia/eclampsia (7.14% vs. 3.12%), GDM (22.53% vs. 13.77%), and low birth weight (4.95% vs. 2.08%) than did those without dyslipidaemia. However, after adjusting for prepregnancy body mass index (pre-BMI), dyslipidaemia was no longer related to these risks. Furthermore, elevated TG dyslipidaemia in SCH patients was connected to an enhanced potential of gestational hypertension (odds ratio [OR]: 2.687, 95% confidence interval [CI]: 1.074 ~ 6.722), and elevated LDL-C dyslipidaemia correlated with increased preeclampsia/eclampsia risk (OR: 3.172, 95% CI: 1.204 ~ 8.355) after accounting for age, smoking status, alcohol use, pre-BMI, and levothyroxine use. Additionally, the combination of TC, TG, LDL-C, pre-BMI, and TSH exhibited enhanced predictive capabilities for gestational hypertension, preeclampsia/eclampsia, and GDM. Values of 0.767, 0.704, and 0.706 were obtained from the area under the curve.

CONCLUSIONS

Among pregnant women with SCH, dyslipidaemia in early pregnancy was related to elevated risks of adverse pregnancy consequences. The combined consideration of age, pre-BMI, TSH, and lipid levels in the first trimester could be beneficial for monitoring patients and implementing interventions to reduce adverse pregnancy outcomes.

Trimester-specific hemodynamics of per- and polyfluoroalkyl substances and its relation to lipid profile in pregnant women

Per- and polyfluoroalkyl substances (PFAS) are persistent organic pollutants widely detected in blood from pregnant women, yet limited study evaluated the trimester-specific variance of serum PFAS, and even less is known for the window of vulnerability to lipids metabolism interrupting effects of PFAS during pregnancy. We quantified 16 legacy, 3 emerging PFAS, and lipid biomarkers in 286 serum samples from 118 pregnant women. All target PFAS, except perfluorotridecanoic acid (PFTrDA), in maternal serum showed moderate to low temporal irregular variability across gestation (average intraclass correlation coefficients ≥ 0.57), while the generalized estimating equations showed a significant declining trend in the serum levels during pregnancy (p for trend < 0.05). The decline of 6:2 chlorinated polyfluorinated ether sulfonate in maternal serum was the greatest with a change of - 21.63% from 1st to 2nd trimester, which indicated a possible higher accumulation of this emerging PFAS in fetal compartment. Multiple linear regression, multiple informant model and Bayesian kernel machine regression showed a higher vulnerability in the 1st trimester to effects of PFAS exposure on serum lipids of pregnant women. The results highlighted the importance of the study timing of PFAS exposure during pregnancy.

Maternal Plasma Lipid Profile and Risk of Spontaneous Preterm Labor Study in a Sample of Iranian Women in 2019

Background

Neonatal problems and adverse outcomes may be minimized by up to 90-75% when preterm delivery is diagnosed early and managed properly. This study aimed to determine the association of maternal plasma lipid indices with the occurrence of spontaneous preterm labor.

Material and Methods

This matched pair case-control study was performed on 80 pregnant women referred to a teaching hospital in Tehran for childbirth in 2019. The lipid profile was assessed in women with spontaneous preterm labor and term birth. According to age, Body Mass Index (BMI), pregnancy number, employment status, and educational level, the women in each group were paired. Data were analyzed using an independent-samples t-test, Mann-Whitney U-test, Chi-square, linear regression, and conditional logistic regression.

Results

Mean serum levels of total cholesterol, triglycerides, and low-density lipoprotein were all significantly higher in the case group compared with the control group (p < 0.05). The conditional logistic regression test confirmed that this association remained significant even after adjusting the effect of potentially confounding factors such as maternal age and body mass index. In addition, in linear regression the increased levels of triglyceride, total cholesterol, and low-density lipoprotein were found to be associated with 3.33-fold (1.32.-5.32 95% CI, p < 0.001), 2.94-fold (1.60-3.14 95% CI, p = 0.002), and 2.46-fold (1.31.-2.91 95% CI, p = 0.006) increased risk of preterm labor, respectively.

Conclusions

High triglyceride, total cholesterol, and low-density lipoprotein serum levels may be linked to an increased chance of spontaneous preterm labor, which might be considered a risk factor for this pregnancy problem.

Association between second- and third-trimester maternal lipid profiles and adverse perinatal outcomes among women with GDM and non-GDM: a retrospective cohort study

BACKGROUND

Lipid metabolism disorder during pregnancy has been reported in women with gestational diabetes mellitus (GDM). However, controversy remains regarding the relationship between maternal changes in lipid profiles and perinatal outcomes. This study investigated the association between maternal lipid levels and adverse perinatal outcomes in women with GDM and non-GDM.

METHODS

In total, 1632 pregnant women with GDM and 9067 women with non-GDM who delivered between 2011-2021 were enrolled in this study. Serum samples were assayed for fasting total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL), and high-density lipoprotein (HDL) levels during the second and third trimesters of pregnancy. Adjusted odds ratios (AOR) and 95% confidence intervals (95% CI) were calculated via multivariable logistic regression analysis to determine the association of lipid levels with perinatal outcomes.

RESULTS

The serum TC, TG, LDL, and HDL levels in the third trimester were significantly higher than those in the second trimester (p < 0.001). Women with GDM had significantly higher levels of TC and TG in the second and third trimesters than those with non-GDM in the same trimesters, while HDL levels decreased in women with GDM (all p < 0.001). After adjusting for confounding factors by multivariate logistic regression, every mmol/L elevation in TG levels of women with GDM in second and third trimesters was associated with a higher risk of caesarean section (AOR = 1.241, 95% CI: 1.103-1.396, p < 0.001; AOR = 1.716, 95% CI: 1.556-1.921, p < 0.001), large for gestational age infants (LGA) (AOR = 1.419, 95% CI: 1.173-2.453, p = 0.001; AOR = 2.011, 95% CI: 1.673-2.735, p < 0.001), macrosomia (AOR = 1.220, 95% CI: 1.133-1.643, p = 0.005; AOR = 1.891, 95% CI: 1.322-2.519, p < 0.001), and neonatal unit admission (NUD; AOR = 1.781, 95% CI: 1.267-2.143, p < 0.001; AOR = 2.052, 95% CI: 1.811-2.432, p < 0.001) cesarean delivery (AOR = 1.423, 95% CI: 1.215-1.679, p < 0.001; AOR = 1.834, 95% CI: 1.453-2.019, p < 0.001), LGA (AOR = 1.593, 95% CI: 1.235-2.518, p = 0.004; AOR = 2.326, 95% CI: 1.728-2.914, p < 0.001), macrosomia (AOR = 1.346, 95% CI: 1.209-1.735, p = 0.006; AOR = 2.032, 95% CI: 1.503-2.627, p < 0.001), and neonatal unit admission (NUD) (AOR = 1.936, 95% CI: 1.453-2.546, p < 0.001; AOR = 1.993, 95% CI: 1.724-2.517, p < 0.001), which were higher than the relative risk of these perinatal outcomes in women with non-GDM. Additionally, every mmol/L increase in second and third-trimester HDL levels of women with GDM was associated with decreased risk of LGA(AOR = 0.421, 95% CI: 0.353-0.712, p = 0.007; AOR = 0.525, 95% CI: 0.319-0.832, p = 0.017) and NUD (AOR = 0.532, 95% CI: 0.327-0.773, p = 0.011; AOR = 0.319, 95% CI: 0.193-0.508, p < 0.001), and the risk reduction was not strong than that of women with GDM.

CONCLUSIONS

Among women with GDM, high maternal TG in the second and third trimesters was independently associated with an increased risk of cesarean section, LGA, macrosomia, and NUD. High maternal HDL during the second and third trimesters was significantly associated with decreased risk of LGA and NUD. These associations were stronger than those in women with non-GDM, suggesting the importance of monitoring second and third-trimester lipid profiles in improving clinical outcomes, especially in GDM pregnancies.

The effect of statins exposure during pregnancy on congenital anomalies and spontaneous abortions: A systematic review and meta-analysis

Objective: To assess the effect of statin exposure during pregnancy on congenital anomalies and spontaneous abortions.

Data sources: Electronic databases were searched from inception to January 2022.

Study Eligibility Criteria: Cohort studies and randomized controlled trials (RCTs) evaluate the effect of treatment with statins on congenital anomalies in general and cardiac malformations in particular. Studies evaluating spontaneous abortions were included as a secondary outcome.

Study appraisal and synthesis methods: Pooled odds ratio was calculated using a random-effects model and meta-regression was utilized when applicable.

Results: Twelve cohort studies and RCTs were included in the analysis. Pregnancy outcomes of 2,447 women that received statins during pregnancy were compared to 897,280 pregnant women who did not. Treatment with statins was not associated with a higher risk of overall congenital anomalies (Odd Ratio = 1.1, CI (0.9–1.3), p = 0.33, I2 = 0%). Yet, cardiac malformations were more prevalent among neonates born to statins users (OR = 1.4, CI (1.1–1.8), p = 0.02, I² = 0%). The risk was higher when exposure occurred during the first trimester. This finding was statistically significant in cohort studies, but not in RCTs. Statin treatment was also associated with a higher rate of spontaneous abortions (OR = 1.5, CI (1.1–2.0), p = 0.005, I² = 0%). In meta-regression analysis, no significant association between lipophilic statins and the rate of congenital anomalies was found.

Conclusion: Overall, treatment with statins during pregnancy was not associated with an increased risk of congenital anomalies. A slight risk elevation for cardiac malformation and spontaneous abortions was seen in cohort studies but not in RCTs.

Systematic Review Registration:clinicaltrials.gov, identifier [CRD42020165804 17/2/2020]

The meta-analysis was presented online at 42nd annual meeting of SMFM. January 31-5 February 2022.

Diagnosing Arterial Stiffness in Pregnancy and Its Implications in the Cardio-Renal-Metabolic Chain

Cardio-renal and metabolic modifications during gestation are crucial determinants of foetal and maternal health in the short and long term. The cardio-renal metabolic syndrome is a vicious circle that starts in the presence of risk factors such as obesity, hypertension, diabetes, kidney disease and ageing, all predisposing to a status dominated by increased arterial stiffness and alteration of the vascular wall, which eventually damages the target organs, such as the heart and kidneys. The literature is scarce regarding cardio-renal metabolic syndrome in pregnancy cohorts. The present paper exposes the current state of the art and emphasises the most important findings of this entity, particularly in pregnant women. The early assessment of arterial function can lead to proper and individualised measures for women predisposed to hypertension, pre-eclampsia, eclampsia, and diabetes mellitus. This review focuses on available information regarding the assessment of arterial function during gestation, possible cut-off values, the possible predictive role for future events and modalities to reverse or control its dysfunction, a fact of crucial importance with excellent outcomes at meagre costs.

Associations between maternal mid-pregnancy apolipoprotein A-1, apolipoprotein B, apolipoprotein B/apolipoprotein A-1 ratio and preterm birth

BACKGROUND AND AIMS

Elevated lipid levels during pregnancy have been shown to be related to the risk of preterm birth. Despite the importance of apolipoprotein (Apo) in lipid metabolism and transportation, evidence regarding apolipoprotein levels during pregnancy and preterm birth is still limited. Therefore, we aim to investigate the associations between maternal ApoA-1, ApoB, ApoB/ApoA-1 ratio and preterm birth.

MATERIALS AND METH

Data were extracted from the information system of Guangdong Women and Children Hospital. Lipoprotein levels were tested using Beckman Coulter AU5800 in mid-pregnancy at a median gestational age of 18 w. Maternal serum ApoB, ApoA-1 and ApoB/ApoA-1 ratio were categorized into tertiles. Logistic regression models were performed to evaluate the odds ratios and 95% confidence intervals for preterm birth.

RESULTS

A total of 5,986 maternal-newborn pairs were included in this study. The rate of preterm birth was 5.7% (n = 344). The multivariate-adjusted ORs (95% CI) of preterm birth were 1.51 (1.06, 2.10) for individuals with high ApoB (>90th), 0.63 (0.38, 0.99) for those with low ApoB (<10th), and 1.64 (1.18, 2.24) for those with high ApoB/ApoA-1 (>90th). Subgroup analyses showed that the association of ApoB and preterm birth was only significant among women with pre-pregnancy BMI 18.5-24 kg/m² (OR = 1.36, 95% CI: 1.12-1.65), age at delivery ≥ 35 years (OR = 1.43, 95% CI: 1.12-1.83).

CONCLUSION

Elevated maternal ApoB level and ApoB/ApoA-1 ratio during mid-pregnancy were related to increased risk of preterm birth. Monitoring maternal serum apolipoprotein levels may help to identify the high-risk population of preterm birth.

Association between lipid trajectories during pregnancy and risk of postpartum glucose intolerance after gestational diabetes mellitus: a cohort study

AIMS

To assess lipid trajectories throughout pregnancy in relation to early postpartum glucose intolerance in women with gestational diabetes mellitus (GDM).

METHODS

This prospective cohort study included 221 Chinese women with GDM who completed plasma lipid test in each trimester of pregnancy and oral glucose tolerance test at 6-9 weeks postdelivery between January 1, 2018 and January 8, 2020. Using the group-based trajectory modeling, total cholesterol (TC), triglyceride (TG), low-density lipoprotein-cholesterol (LDL-c), and high-density lipoprotein-cholesterol(HDL-c) were identified separately as three trajectories: low, moderate, and high trajectory. The associations between lipid trajectories and early postpartum glucose intolerance were all evaluated.

RESULTS

Seventy-three participants developed postpartum glucose intolerance. For patients in low, moderate and high trajectory, the incidence of postpartum glucose intolerance was 38.4%, 34.9%, and 17.9%, respectively. GDM women with lower LDL-c trajectories presented a higher risk of postpartum glucose intolerance. The adjusted odds ratio (95% CI) for glucose intolerance was 3.14 (1.17-8.39) in low LDL-c trajectory and 2.68 (1.05-6.85) in moderate trajectory when compared with the high one. However, TC trajectory was not associated with the risk of postpartum glucose intolerance, nor were TG trajectory and HDL-c trajectory. Moreover, a significant difference of insulin sensitivity was observed in participants with different LDL-c trajectories; participants in high LDL-c trajectory had the highest insulin sensitivity, whereas the women in low LDL-c trajectory had the lowest insulin sensitivity (P = 0.02).

CONCLUSIONS

The high trajectory of LDL-c during pregnancy may play a protective role on postpartum glucose intolerance in women with GDM. Further studies are warranted to explore the underlying mechanism. Trial registration The study was reviewed and approved by the Institutional Review Board of The First Affiliated Hospital of Sun Yat-sen University (reference number: [2014]No. 93). All participants provided written informed consent forms, and the ethics committee approved this consent procedure.

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.

Serum lipid levels in relation to clinical outcomes in pregnant women with gestational diabetes mellitus: an observational cohort study

BACKGROUND

Research on dyslipidemia during pregnancy in women with gestational diabetes mellitus (GDM) has rarely been conducted in Asia. The present study aimed to evaluate maternal mid-trimester lipid profile in relation to GDM and clinical outcomes in these high-risk populations.

METHODS

The medical records of 632 pregnant women in the second trimester were retrospectively analyzed. Maternal fasting serum lipids were assayed for total cholesterol (TC), triglycerides (TG), high-density lipoprotein-cholesterol (HDL-C), low-density lipoprotein-cholesterol (LDL-C), apolipoprotein A1 (Apo A1) and Apo B concentrations during the second trimester. The atherogenic index of plasma (AIP) was calculated as log (TG/HDL). The clinical outcomes were collected by evaluating delivery mode, postpartum hemorrhage, prematurity, macrosomia, birth weight, body length and neonatal Apgar 5 min score.

RESULTS

Levels of TG and AIP were elevated while decreased HDL-C was observed in women with GDM compared with that of the control group. Significant differences were observed in gestational weeks at birth, cesarean section, postpartum hemorrhage, birth weight, body length, prematurity and macrosomia between the two groups. Compared with women with hyperlipidemia, the incidence of GDM and cesarean section was lower in normal lipid group. Women in the hyperlipidemia group had smaller gestational weeks at birth than those in the control group. According to the logistic regression analysis, each unit elevation in AIP increased the risk of GDM by 18.48 times (OR = 18.48, CI: 2.38-143.22). Besides, age (OR = 1.11, CI: 1.06-1.16) and pre-pregnancy BMI (OR = 1.15, CI: 1.07-1.24) were the risk factors of GDM.

CONCLUSIONS

These findings suggested that reasonable lipid control in the second trimester might reduce the incidence of GDM and be a potential strategy for improving clinical outcomes in these high-risk women.

Disorders of placental villous maturation are present in one-third of cases with spontaneous preterm labor

OBJECTIVES

Spontaneous preterm labor is an obstetrical syndrome accounting for approximately 65-70% of preterm births, the latter being the most frequent cause of neonatal death and the second most frequent cause of death in children less than five years of age worldwide. The purpose of this study was to determine and compare to uncomplicated pregnancies (1) the frequency of placental disorders of villous maturation in spontaneous preterm labor; (2) the frequency of other placental morphologic characteristics associated with the preterm labor syndrome; and (3) the distribution of these lesions according to gestational age at delivery and their severity.

METHODS

A case-control study of singleton pregnant women was conducted that included (1) uncomplicated pregnancies (controls, n=944) and (2) pregnancies with spontaneous preterm labor (cases, n=438). All placentas underwent histopathologic examination. Patients with chronic maternal diseases (e.g., chronic hypertension, diabetes mellitus, renal disease, thyroid disease, asthma, autoimmune disease, and coagulopathies), fetal malformations, chromosomal abnormalities, multifetal gestation, preeclampsia, eclampsia, preterm prelabor rupture of the fetal membranes, gestational hypertension, gestational diabetes mellitus, and HELLP (hemolysis, elevated liver enzymes and low platelet count) syndrome were excluded from the study.

RESULTS

Compared to the controls, the most prevalent placental lesions among the cases were the disorders of villous maturation (31.8% [106/333] including delayed villous maturation 18.6% [62/333] vs. 1.4% [6/442], q<0.0001, prevalence ratio 13.7; and accelerated villous maturation 13.2% [44/333] vs. 0% [0/442], q<0.001). Other lesions in decreasing order of prevalence included hypercapillarized villi (15.6% [68/435] vs. 3.5% [33/938], q<0.001, prevalence ratio 4.4); nucleated red blood cells (1.1% [5/437] vs. 0% [0/938], q<0.01); chronic inflammatory lesions (47.9% [210/438] vs. 29.9% [282/944], q<0.0001, prevalence ratio 1.6); fetal inflammatory response (30.1% [132/438] vs. 23.2% [219/944], q<0.05, prevalence ratio 1.3); maternal inflammatory response (45.5% [195/438] vs. 36.1% [341/944], q<0.01, prevalence ratio 1.2); and maternal vascular malperfusion (44.5% [195/438] vs. 35.7% [337/944], q<0.01, prevalence ratio 1.2). Accelerated villous maturation did not show gestational age-dependent association with any other placental lesion while delayed villous maturation showed a gestational age-dependent association with acute placental inflammation (q-value=0.005).

CONCLUSIONS

Disorders of villous maturation are present in nearly one-third of the cases of spontaneous preterm labor.

Maternal Serum Antioxidants in Mid Pregnancy and Risk of Preterm Delivery and Small for Gestational Age Birth: Results from a Prospective Pregnancy Cohort

Background: Preterm delivery (PTD) and poor fetal growth are major contributors to neonatal mortality and morbidity that can extend from birth onward. Although overt maternal nutrient deficiencies are associated with adverse pregnancy outcomes, such deficiencies are rare in developed countries. However, some evidence suggests that even within the normal range, higher levels of antioxidant nutrients are protective against adverse pregnancy outcomes. Materials and Methods: Using data from the prospective Pregnancy Outcomes and Community Health (POUCH) Study (n = 301 preterm; n = 246 term), we examined associations between maternal blood levels of selected antioxidants and pregnancy outcomes. Serum collected at 16-27 weeks' gestation was analyzed for carotenoids, retinol, and α- and γ-tocopherol. Using weighted polytomous regression, these nutrient concentrations were assessed in relation to (1) PTD (<37 weeks gestation) overall and grouped as spontaneous or medically indicated; and (2) small for gestational age (SGA) defined as birthweight-for-gestational age <10th percentile of a national reference population. Results: Women with total serum carotenoids in the upper quartile (Q4) had significantly lower odds of medically indicated PTD compared with women in the lower quartiles (Q1-Q3) even after adjustment for maternal characteristics (aOR = 0.4; 95% CI: 0.2-0.9). Odds ratios for SGA were consistently ≤0.5 among women with any of the serum nutrients in Q4 as compared with Q1-Q3, but final models did not reach statistical significance. Conclusion: Results support the possibility that high maternal serum antioxidants and/or the larger dietary or lifestyle pattern they represent may play a protective role in preventing adverse pregnancy outcomes.

Are maternal metabolic syndrome and lipid profile associated with preterm delivery and preterm premature rupture of membranes?

AIM

We aimed to evaluate the association of metabolic syndrome (MetS), its components and lipid profile in mid-pregnancy with preterm delivery and preterm premature rupture of membranes (PPROM).

METHODS

This prospective cohort study was conducted on 203 pregnant women between 24 and 28 weeks of gestation, undergoing gestational diabetes screening test with 50 g glucose challenge test (GCT). Fasting serum total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglyceride (TG) levels were measured during the week after GCT assessment. Information on the participants' pre-pregnancy weight, demographic/reproductive characteristics, and height and blood pressure (BP) measurements were documented at baseline entry into the study. Metabolic syndrome was defined as the co-existence of 3 or more of the following criteria: Body mass index (BMI) before pregnancy ≥ 30 kg/m², BP ≥ 130/85 mmHg, GCT ≥ 140 mg/dl, TG ≥ 150 mg/dl, and HDL-C ≤ 50 mg/dl. All participants were followed through routine prenatal care, up to delivery. Any deliveries or rupture of membranes of less than 37 weeks of pregnancy were considered preterm delivery and PPROM, respectively. Statistical analysis was performed by SPSS V.20, and p value of less than 0.05 was considered significant.

FINDINGS

MetS was detected in 10 (4.9%) of participants. Logistic regression analysis showed HDL-C levels, and hypertension were associated with spontaneous preterm delivery [(OR 0.952, 95% CI 0.910-0.995), (OR 1.629, 95% CI 1.554-1.709) respectively], but no statistically significant results were found for PPROM.

CONCLUSIONS

Low HDL-C levels and hypertension in mid-pregnancy are associated with the occurrence of spontaneous preterm deliveries, indicating that MetS and its components should be monitored more closely in pregnancy.

Maternal plasma lipid levels across pregnancy and the risks of small-for-gestational age and low birth weight: a cohort study from rural Gambia

Background

Sub-optimal maternal lipid levels during pregnancy may be implicated in the pathophysiological mechanisms leading to low birth weight (LBW) and small-for-gestational-age (SGA). We aimed to determine whether maternal lipid levels across pregnancy were associated with birth weight and the risks of LBW and SGA in rural Gambia.

Methods

This secondary analysis of the ENID trial involved 573 pregnant women with term deliveries. Plasma levels of total cholesterol (TC), high-density lipoprotein cholesterol (HDL-c), low-density lipoprotein cholesterol (LDL-c), and triglycerides (TG) were analyzed at enrolment (mean (SD) = 13.9 (3.3) weeks gestation), 20 and 30 weeks gestation as continuous variables and percentile groups. Regression models with adjustment for confounders were used to examine associations between gestational lipid levels and birth weight and the risks of LBW (birth weight < 2500 g) and SGA (<10th percentile INTERGROWTH-21ST for birth weight).

Results

There were 7.9% LBW and 32.5% SGA infants. At enrolment, every unit increase in HDL-c was associated with a 2.7% (P = 0.011) reduction in relative risk of LBW. At 20 weeks gestation, every unit increase in TC levels was associated with a 1.3% reduction in relative risk of LBW (P = 0.002). Low (<10th percentile) HDL-c at enrolment or at 20 weeks gestation was associated with a 2.6 (P = 0.007) and 3.0 (P = 0.003) times greater risk of LBW, respectively, compared with referent (10th─90th) HDL-c. High (>90th percentile) LDL-c at 30 weeks gestation was associated with a 55% lower risk of SGA compared with referent LDL-c (P = 0.017). Increased levels of TC (β = 1.3, P = 0.027) at 20 weeks gestation and of TC (β = 1.2, P = 0.006) and LDL-c (β = 1.5, P = 0.002) at 30 weeks gestation were all associated with higher birth weight.

Conclusions

In rural Gambia, lipid levels during pregnancy were associated with infant birth weight and the risks of LBW and SGA. Associations varied by lipid class and changed across pregnancy, indicating an adaptive process by which maternal lipids may influence fetal growth and birth outcomes.

Trial registration

This trial was registered as ISRCTN49285450 on: 12/11/2009.

Elevated Midtrimester Triglycerides as a Biomarker for Postpartum Hyperglycemia in Gestational Diabetes

BACKGROUND

Whether elevated triglyceride (TG) levels during pregnancy were a biomarker for postpartum abnormal glucose metabolism (AGM) in women with previous gestational diabetes mellitus (GDM) remained unknown. The aim of this study was to investigate the association between TG levels during the second trimester and postpartum AGM in GDM women.

METHODS

This was a retrospective cohort study including 513 GDM women. A 75 g oral glucose tolerance test (OGTT) was performed, and lipid levels were determined during pregnancy and the postpartum period. GDM patients were categorized into tertiles according to their TG levels at 24-28 weeks of gestation (TG < 2.14 mmol/L, TG: 2.14-2.89 mmol/L, and TG > 2.89 mmol/L). A logistic regression model was used to calculate the odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

During pregnancy, women in the high TG tertile showed higher HbA1c levels (5.47 ± 0.58% versus 5.28 ± 0.49%, p = 0.006), higher total cholesterol (TC) levels (5.85 ± 1.23 mmol/L versus 5.15 ± 0.97 mmol/L, p = 0.026), and higher HOMA-IR (2.36 (1.62-3.45) versus 1.49 (0.97-2.33), p < 0.001) than the participants in the low TG tertile. After delivery, the prevalence rates of AGM based on above tertiles of TG levels during pregnancy were 26.90%, 33.33%, and 43.27%, respectively (p = 0.006). High TG tertile during the second trimester was associated with the presence of postpartum AGM (adjusted OR: 2.001, 95% CI: 1.054-3.800, p = 0.034).

CONCLUSIONS

The elevated midtrimester TG levels were not only accompanied by higher glucose and lipid levels and more severe insulin resistance at the time of the measurement but were a biomarker for postpartum AGM as well.

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.

Complications of pregnancy in morbidly obese patients: What is the impact of gestational diabetes mellitus?

OBJECTIVES

The synergistic role of severe obesity and gestational diabetes mellitus (GDM) on pregnancy complications has been poorly studied. We aim to analyze the impact of GDM on pregnancy complications in women with class III obesity.

MATERIAL AND METHODS

we performed a retrospective monocentric study including women with a pregestational BMI≥40kg/m2 with a singleton pregnancy from January 1996 to December 2014. We compared the risks of maternal, fetal and neonatal complications between patients with GDM and those without GDM.

RESULTS

We included 354 patients, 121 (34.3%) had GDM and 63 needed insulin treatment (52.9% of the GDM women). Patients with GDM were older (30.4±5.1 vs 28.9±4.8 years,p=0.008) and had more frequently a history of GDM (24.8% vs 6.1%; p<0.0001). Patients with GDM were more often hospitalized (47.8% vs 29.8%, p=0.001) and were more likely to have premature birth (11.7% vs. 5.3%, p=0.031). Neonates from mothers with GDM were more frequently large for gestational age (31.6% vs 19.4%, p=0.011), and had a higher rate of transfers to neonatal intensive unit (9.2% vs 4.0%, p=0.047). There was no difference for preeclampsia, C-section, shoulder dystocia, neonatal hypoglycemia or postpartum complications. Outcomes were comparable in women with or without insulin therapy.

CONCLUSION

The rate of GDM is particularly high in class III obese women. Morbidly obese women with GDM were more at risk for complications and needed more often insulin therapy. Our results suggest to pay a particular attention in this high-risk population.

Genetic Risk Scores for Maternal Lipid Levels and Their Association with Preterm Birth

Maternal lipid profiles are associated with risk for preterm birth (PTB), although the lipid component and effect size are inconsistent between studies. It is also unclear whether these associations are the result of excessive changes in lipid metabolism during pregnancy or genetic variability in genes controlling basal lipid metabolism. This study investigates the association between genetic risk scores (GRS) for four lipid components (high-density lipoprotein [HDL-C], low-density lipoprotein [LDL-C], triacylglycerols [TAG], and total cholesterol [TC]) with risk for PTB. Subjects included 954 pregnant women from California for whom second trimester serum samples were available, of which 479 gave birth preterm and 475 gave birth at term. We genotyped 96 single-nucleotide polymorphisms, which were selected from genome-wide association studies of lipid levels in adult populations. Lipid-specific GRS were constructed for HDL-C, LDL-C, TAG, and TC. The associations between GRS and PTB were analyzed using logistic regression. A higher HDL-C GRS was associated with increased risk for PTB overall and spontaneous PTB. Higher TAG and TC GRS were associated with decreased risk for PTB overall and spontaneous PTB. This study identifies counter-intuitive associations between lipid GRS and spontaneous PTB. Further replication studies are needed to confirm these findings, but they suggest that our current scientific understanding of the relationship between lipid metabolism, PTB, and genetics is incomplete.

The Association of Polymorphisms in Circadian Clock and Lipid Metabolism Genes With 2nd Trimester Lipid Levels and Preterm Birth

Deregulation of the circadian system in humans and animals can lead to various adverse reproductive outcomes due to genetic mutations and environmental factors. In addition to the clock, lipid metabolism may also play an important role in influencing reproductive outcomes. Despite the importance of the circadian clock and lipid metabolism in regulating birth timing few studies have examined the relationship between circadian genetics with lipid levels during pregnancy and their relationship with preterm birth (PTB). In this study we aimed to determine if single nucleotide polymorphisms (SNPs) in genes from the circadian clock and lipid metabolism influence 2^nd trimester maternal lipid levels and if this is associated with an increased risk for PTB. We genotyped 72 SNPs across 40 genes previously associated with various metabolic abnormalities on 930 women with 2^nd trimester serum lipid measurements. SNPs were analyzed for their relationship to levels of total cholesterol, high density lipoprotein (HDL), low density lipoprotein (LDL) and triglycerides (TG) using linear regression. SNPs were also evaluated for their relationship to PTB using logistic regression. Five SNPs in four genes met statistical significance after Bonferroni correction (p < 1.8 × 10^-4) with one or more lipid levels. Of these, four SNPs were in lipid related metabolism genes: rs7412 in APOE with total cholesterol, HDL and LDL, rs646776 and rs599839 in CELSR2-PSRC1-SORT1 gene cluster with total cholesterol, HDL and LDL and rs738409 in PNPLA3 with HDL and TG and one was in a circadian clock gene: rs228669 in PER3 with TG. Of these SNPs only PER3 rs228669 was marginally associated with PTB (p = 0.02). In addition, PER3 rs228669 acts as an effect modifier on the relationship between TG and PTB.

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.

Second-trimester maternal lipid profiles predict pregnancy complications in an age-dependent manner

PURPOSE

Our objective was to investigate the combinatorial effect of maternal age and second-trimester maternal lipid profiles for pregnancy complications.

METHODS

With 1:4 matching, this retrospective study selected 499 advanced maternal age women and 1996 younger controls. Logistic regression analysis was used to estimate the correlation between second-trimester lipid profiles [total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C)] and pregnancy complications [gestational diabetes mellitus (GDM), pregnancy-induced hypertension syndrome (PIH), preterm labor (PTL), and macrosomia]. Optimal cutoff points were determined by ROC curve analysis.

RESULTS

In women aged 20-34 years, TG are a risk factor for PIH (OR 1.54, 95% CI 1.16-2.04) and PTL (OR 1.34, 95% CI 1.04-1.72). LDL-C was positively associated with macrosomia (OR 1.25, 95% CI 1.04-1.50), while HDL-C was negatively associated with PIH (OR 0.45, 95% CI 0.21-0.93). The optimal cutoff points for TG predicting PIH and PTL were separately ≥ 2.135 and 2.305 mmol/L. The optimal cutoff point for HDL-C identifying PIH was ≤ 1.995 mmol/L and for LDL-C identifying macrosomia was ≥ 3.425 mmol/L. As for advanced maternal age, only TG was an independent risk factor for PIH (OR 1.60, 95% CI 1.01-2.54), and its optimal cutoff point was ≥ 2.375 mmol/L.

CONCLUSIONS

Second-trimester lipid profiles might predict pregnancy complications varied by maternal age. This suggested that individualized prenatal care strategies should be established for women with advanced and normal maternal age to prevent pregnancy complications.

Association of maternal serum copper during early pregnancy with the risk of spontaneous preterm birth: A nested case-control study in China

BACKGROUND

The effect of maternal copper (Cu) level on the risk of spontaneous preterm birth (SPB) remains debate. Therefore, we conducted a prospective nested case-control study in Shanxi Province to investigate the relationship between maternal serum Cu concentration and SPB risk, as well as the potential mediation effect of lipid metabolism.

METHOD

From an overall cohort of 4229 women, 147 women affected by SPB at 20-36 gestational weeks (cases) and 381 women who delivered at ≥37 gestational weeks (controls) were included in our nested case-control study. Maternal blood samples were collected during 4-22 gestational weeks, and the concentrations of Cu, total cholesterol (TC), and triglycerides (TG) were measured. Information on maternal social demographic characteristics were collected using questionnaires. Unconditional logistic regression models were used to estimate the associations of Cu, TC or TG levels with SPB risk. Linear regressions were used to assess the relationships between concentrations of Cu and TC or TG.

RESULTS

Serum Cu concentrations in the case group (median: 184 μg/dL) were significantly higher than those in the control group (median: 166 μg/dL, p < 0.0001). Compared to the lowest serum Cu levels, the odds ratios associated with SPB increased to 2.02 (95% confidence interval [CI]: 1.07, 3.82), 3.10 (1.54, 6.22) and 4.18 (2.11, 8.27) in the second, third and fourth quartile respectively, after adjusting for sampling time, maternal age, pre-pregnancy BMI, education, occupation, parity, spontaneous abortion history, folic acid use, medication use, pre-pregnancy passive smoking status, child gender and fasting status. Plasma concentrations of TC and TG were positively associated with SPB risk in a dose-dependent manner. However, when stratified by sampling time, the above-mentioned relationships were significant in the first trimester but not in the second. In addition, plasma concentrations of TC and TG were positively correlated with serum Cu concentrations.

CONCLUSIONS

High maternal Cu level in the first trimester may increase the risk of SPB, by potentially increasing plasma concentrations of TC and TG.

Acute Postexercise Change in Circulating Irisin Is Related to More Favorable Lipid Profile in Pregnant Women Attending a Structured Exercise Program and to Less Favorable Lipid Profile in Controls: An Experimental Study with Two Groups

INTRODUCTION

The blood irisin concentrations may be affected both by exercise and pregnancy. We aimed to determine acute responses in serum irisin after a single exercise session and relationships between exercise-induced changes in this hormone and lipid profile in pregnancy.

MATERIAL AND METHODS

It was an experimental study in 20 Caucasian women in normal pregnancy (age 30 ± 3 years, 28 ± 6 weeks of gestation; mean ± SD). Participants were assigned to training (n = 8) and control groups (n = 12). Before the experiment, women from the training group attended a structured exercise program 3 times a week for 6 weeks. Blood samples were collected before and 30 minutes after a single bout of 60-minute moderate- to high-intensity exercise to determine serum levels of irisin, insulin, glucose concentration, and lipid profile.

RESULTS

At baseline, we recorded slightly lower irisin levels in the training group compared to controls (12.2 ± 2.4 and 13.9 ± 3.3 ng · ml^-1, respectively). Only in the training group all women presented increase in irisin levels after exercise (on average by 14%); and this change was statistically significant (p = 0.002). In the controls, we found positive significant relationships between postexercise irisin change and low-density lipoproteins (R = 0.594; p = 0.04) and total cholesterol (R = 0.734; p = 0.006). Surprisingly, in the training group, these relationships were also significant but inverse (R = -0.738 and p = 0.036; R = -0.833 and p = 0.01, respectively).

CONCLUSIONS

Training and control pregnant women responded differently to a single exercise session, both in the postexercise change in irisin and its relationship to the blood lipids. Only in the training group we observed the postexercise increase in irisin, which was related to more favorable lipid profile. Systematic prenatal physical activity may optimize the postexercise irisin response and lipid metabolism regulated by this hormone. Therefore, exercise programs should be promoted in pregnant women and obstetric care providers.

Maternal dyslipidemia and risk for preterm birth

Maternal lipid profiles during pregnancy are associated with risk for preterm birth. This study investigates the association between maternal dyslipidemia and subsequent preterm birth among pregnant women in the state of California. Births were identified from California birth certificate and hospital discharge records from 2007-2012 (N = 2,865,987). Preterm birth was defined as <37 weeks completed gestation and dyslipidemia was defined by diagnostic codes. Subtypes of preterm birth were classified as preterm premature rupture of membranes (PPROM), spontaneous labor, and medically indicated, according to birth certificate data and diagnostic codes. The association between dyslipidemia and preterm birth was tested with logistic regression. Models were adjusted for maternal age at delivery, race/ethnicity, hypertension, pre-pregnancy body mass index, insurance type, and education. Maternal dyslipidemia was significantly associated with increased odds of preterm birth (adjusted OR: 1.49, 95%CI: 1.39, 1.59). This finding was consistent across all subtypes of preterm birth, including PPROM (adjusted OR: 1.54, 95%CI: 1.34, 1.76), spontaneous (adjusted OR: 1.51, 95%CI: 1.39, 1.65), and medically indicated (adjusted OR: 1.454, 95%CI: 1.282, 1.649). This study suggests that maternal dyslipidemia is associated with increased risk for all types of preterm birth.

Influence of aerobic exercise on maternal lipid levels and offspring morphometrics

BACKGROUND

Maternal BMI, lipid levels (cholesterol, triglyceride, LDL, HDL), and exercise amount are interrelated and each influence offspring body size. This study proposed to determine the influence of exercise on maternal lipid levels and infant body size.

METHODS

We had 36 participants complete these measures. Participants in the aerobic exercise intervention (n = 14) completed three 50-min sessions weekly from 16 weeks gestation to delivery and were compared with a non-exercise control group (n = 22). Maternal lipid profiles were assessed at 16 and at 36 weeks gestation. Fetal body size was measured at 36 weeks gestational age using ultrasound assessment. Neonatal body size measures were acquired from birth records. Statistical analysis included two-sample t-tests, correlations, and regression models.

RESULTS

Participants were similar in age, pre-pregnancy BMI, gravida, parity, education, and gestational weight gain (GWG). There were no differences in gestational age, Apgar scores at 1 and 5 min for infants of exercisers relative to controls. Exercisers had higher pre-training triglycerides (p = 0.004) and pregnancy change in triglycerides (p = 0.049) compared to controls. Head circumference was significantly larger in exercise exposed infants relative to infants of controls. Pregnancy METs had a positive relationship with birth length (r = .445, p = .006) and birth weight (r = .391, p = .02). GWG had a moderate, positive relationship with fetal abdominal circumference (r = .570, p = .004). Regression analysis indicated 5 predictors explained 61.7% of the variance in birth weight (Adj.R² = 0.469, F(5,13) = 5,13, p = 0.02); it was found that pregnancy METs (β = .724, p = .007), 36 week cholesterol (β = 1.066, p = .02), and 36 week LDL (β = -1.267, p = .006) significantly predict birth weight. Regression analysis indicated 4 predictors explained 43.8% of the variance in birth length (Adj.R² = 0.306, F(4,17) = 3.32, p = 0.04); it was found that pregnancy METs (β = .530, p = .03), and 36 week LDL (β = -.891, p = .049) significantly predict birth length.

CONCLUSION

The primary association and predictors of infant body size was related to pregnancy exercise and late pregnancy cholesterol and LDL levels. Considering these relationships, it is essential that women maintain aerobic exercise during pregnancy, but should also be cognizant of lipid levels during their pregnancy. Therefore intervention during pregnancy focused on infant body size should involve exercise and and quality nutritional intake foods during pregnancy.

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.

Dyslipidemia in pregnancy and maternal-fetal outcome

Hyperlipidemia is a known cause of atherosclerosis and directly contributes to the current epidemic in cardio-vascular disease. Pregnancy is typified by an increase in serum levels of total cholesterol and triglycerides pushed by the rise in estrogen, progesterone and lactogen. Mobilization of stored fat depots in late pregnancy may provide a reservoir of fatty acids for fetal growth and placental tissue steroid synthesis. This physiologic increase in lipids performs an essential role during pregnancy; however, elevated levels of lipids in predisposed women or with familiar forms of hyperlipidemia can carry increased risk for maternal-fetal complications. The present treatment of pregnant women with hyperlipidemia is the suspension of medications. However, hyperlipidemia during pregnancy is associated with preeclampsia, preterm birth and gestational diabetes and offspring of these mothers show a propensity to enhanced fatty streak formation and an increased risk of progressive atherosclerosis. This current evidence may motivate the further study on the potential benefits of treatment of hyperlipidemia in pregnancy and its effects on maternal-fetal outcomes.

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.

Common carotid artery intima-media thickness increases throughout the pregnancy cycle: a prospective cohort study

Background

High parity is associated with greater cardiovascular disease (CVD) among mid-life and older women. Prospective studies of arterial change throughout pregnancy are needed to provide insight into potential mechanisms. This study assessed vascular adaptation across pregnancy in healthy first-time pregnant women.

Methods

The Maternal Vascular Adaptation to Healthy Pregnancy Study (Pittsburgh, PA, 2010–2015) assessed 37 primigravid women each trimester, 6–8 weeks after delivery and 1–5 years postpartum, with B-mode ultrasound imaging of common carotid artery (CCA) intima-media thickness (IMT) and inter-adventitial diameter (IAD) to assess associations with physical and cardiometabolic measures.

Results

Thirty-seven women (age 28.2 ± 4.5 years, pre-pregnant BMI 24.4 ± 3.2 kg/m²) experienced uncomplicated pregnancies. After adjustment for age and pre-pregnancy BMI, mean (SE) IAD (mm) increased each trimester, from 6.38 (0.08) in the 1st trimester to 6.92 (0.09) in the 3rd trimester, and then returned to 1st trimester levels postpartum (6.35 [0.07], P <  0.001). In contrast, mean (SE) CCA IMT (mm) increased from the 2nd trimester (i.e., 0.546 [0.01]) onward, and remained higher at an average of 2.7 years postpartum (0.581 [0.02], P = 0.03). Weight partially explained changes in IAD.

Conclusions

In uncomplicated first pregnancies, IAD increased and returned to 1st trimester levels postpartum. In contrast, CCA IMT remained increased 2 years postpartum. Maternal weight explained vascular changes better than did metabolic changes. Increased postpartum CCA IMT may persist and contribute to long-term CVD risk.

Electronic supplementary material

The online version of this article (10.1186/s12884-018-1841-y) contains supplementary material, which is available to authorized users.

Dyslipidemia and maternal obesity: Prematurity and neonatal prognosis

Summary Objective: To identify the changes caused by dyslipidemia and obesity in pregnancy suggesting causes for premature birth, and the prognosis for the newborn. Method: Systematic review based on the Medline, Lilacs, Embase and Cochrane library databases between 1996 and 2016. The search for studies included the following keywords: “dyslipidemia, pregnancy, obesity, preterm birth.” A protocol was programmed and a protocol for inclusion/exclusion of studies was implemented. Results: Of the 5,789 articles initially selected between March 1996 and July 2016, only 32 were in accordance with the established criteria. Of these, 28.12% discussed risk factors of prematurity; 37.50%, metabolic alterations and gestational dyslipidemia; 21.87%, dyslipidemic complications in preterm birth; and 12,50%, lipid metabolism, glycemic and placental transfer. Conclusion: There is a reduced adaptation of obese pregnant women to the metabolic changes of gestation. This favors dyslipidemic intercurrences in the mother, which, directly or indirectly, suggests the occurrence of premature births and high lipid transfer to the fetus. Therefore, preterm newborns, whose mothers were dyslipidemic during pregnancy, have greater risk of epicardial fat, both in early (first year of life) and in later (adult) phases of life.

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.

Preterm Delivery and Future Risk of Maternal Cardiovascular Disease: A Systematic Review and Meta-Analysis

Background

Preterm delivery (<37 weeks gestational age) affects 11% of all pregnancies, but data are conflicting whether preterm birth is associated with long‐term adverse maternal cardiovascular outcomes. We aimed to systematically evaluate and summarize the evidence on the relationship between preterm birth and future maternal risk of cardiovascular diseases.

Methods and Results

A systematic search of MEDLINE and EMBASE was performed to identify relevant studies that evaluated the association between preterm birth and future maternal risk of composite cardiovascular disease, coronary heart disease, stroke, and death caused by cardiovascular or coronary heart disease and stroke. We quantified the associations using random effects meta‐analysis. Twenty‐one studies with over 5.8 million women, including over 338 000 women with previous preterm deliveries, were identified. Meta‐analysis of studies that adjusted for potential confounders showed that preterm birth was associated with an increased risk of maternal future cardiovascular disease (risk ratio [RR] 1.43, 95% confidence interval [CI], 1.18, 1.72), cardiovascular disease death (RR 1.78, 95% CI, 1.42, 2.21), coronary heart disease (RR 1.49, 95% CI, 1.38, 1.60), coronary heart disease death (RR 2.10, 95% CI, 1.87, 2.36), and stroke (RR 1.65, 95% CI, 1.51, 1.79). Sensitivity analysis showed that the highest risks occurred when the preterm deliveries occurred before 32 weeks gestation or were medically indicated.

Conclusions

Preterm delivery is associated with an increase in future maternal adverse cardiovascular outcomes, including a 2‐fold increase in deaths caused by coronary heart disease. These findings support the assessment of preterm delivery in cardiovascular risk assessment in women.

Preterm birth with placental evidence of malperfusion is associated with cardiovascular risk factors after pregnancy: a prospective cohort study

OBJECTIVE

Preterm birth (PTB) is associated with excess maternal cardiovascular disease risk. We considered that women with PTB and placental evidence of maternal malperfusion would be particularly affected.

DESIGN

Pregnancy cohort study.

SETTING

Pittsburgh, PA, USA.

POPULATION

Women with PTB (n = 115) and term births (n = 210) evaluated 4-12 years after pregnancy.

METHODS

Cardiometabolic risk markers were compared in women with prior PTB versus term births; pre-eclampsia and growth restriction cases were excluded. Placental evidence of maternal vascular malperfusion (vasculopathy, infarct, advanced villous maturation, perivillous fibrin, intervillous fibrin deposition), acute infection/inflammation (chorioamnionitis, funisitis, deciduitus) and villitis of unknown aetiology (chronic inflammation) was used to classify PTBs.

MAIN OUTCOME MEASURES

Carotid artery intima-media thickness (IMT), fasting lipids, blood pressure (BP) and inflammatory markers measured after delivery.

RESULTS

Women with PTB and malperfusion lesions had higher total cholesterol (+13.5 mg/dl) and systolic BP (+4.0 mmHg) at follow up compared with women with term births, accounting for age, race, pre-pregnancy BMI, and smoking (P < 0.05). Women with PTB and malperfusion accompanied by inflammatory lesions had the most atherogenic profile after pregnancy (cholesterol +18.7, apolipoprotein B + 12.7 mg/dl; all P < 0.05), adjusted for pre-pregnancy features. Carotid IMT was higher in this group (+0.037 cm, P = 0.031) accounting for pre-pregnancy factors; differences were attenuated after adjusting for BP and atherogenic lipids at follow up (+0.027, P = 0.095).

CONCLUSION

PTBs with placental malperfusion were associated with an excess maternal cardiometabolic risk burden in the decade after pregnancy. The placenta may offer insight into subtypes of PTB related to maternal cardiovascular disease.

TWEETABLE ABSTRACT

Preterm births with placental malperfusion may mark women at higher cardiovascular disease risk.

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.

Impact of the Use of Different Diagnostic Criteria in the Prevalence of Dyslipidemia in Pregnant Women

Background

There is a physiologic elevation of total cholesterol (TC) and triglycerides (TG) during pregnancy. Some authors define dyslipidemia (DLP) in pregnant women when TC, LDL and TG concentrations are above the 95th percentile (p95%) and HDL concentration is below the 5th percentile (P5%) for gestational age (GA).

Objective

To compare the prevalence of DLP in pregnant women using percentiles criteria with the V Brazilian Guidelines on Dyslipidemia and the association with maternal and fetal outcomes.

Results

Pregnant women with high-risk conditions, aged 18-50 years, and at least one lipid profile during pregnancy was classified as the presence of DLP by two diagnostic criteria. Clinical and laboratorial data of mothers and newborns were evaluated.

Conclusion

433 pregnant women aged 32.9 ± 6.5 years were studied. Most (54.6%) had lipid profile collected during third trimester. The prevalence of any lipid abnormalities according to the criteria of the National Guidelines was 83.8%: TC ≥ 200 mg/dL was found in 49.9%; LDL ≥ 160 mg/dL, in 14.3%, HDL ≤ 50 mg/dL in 44.4% and TG ≥ 150 mg/dL in 65.3%. Any changes of lipid according to percentiles criteria was found in 19.6%: elevation above the P95% for TC was found in 0.7%; for LDL, 1.7%; for TG 6.4% and HDL lower than the P5% in 13%. The frequency of comorbidity: hypertension, diabetes, smoking, obesity and preeclampsia was similar among pregnant women when DLP was compared by both criteria.

Conclusion

The prevalence of DLP during pregnancy varies significantly depending on the criteria used, however none demonstrated superiority in association with comorbidities.

Localization of the placental BCRP/ABCG2 transporter to lipid rafts: Role for cholesterol in mediating efflux activity

INTRODUCTION

The breast cancer resistance protein (BCRP/ABCG2) is an efflux transporter in the placental barrier. By transporting chemicals from the fetal to the maternal circulation, BCRP limits fetal exposure to a range of drugs, toxicants, and endobiotics such as bile acids and hormones. The purpose of the present studies was to 1) determine whether BCRP localizes to highly-ordered, cholesterol-rich lipid raft microdomains in placenta microvillous membranes, and 2) determine the impact of cholesterol on BCRP-mediated placental transport in vitro.

METHODS

BCRP expression was analyzed in lipid rafts isolated from placentas from healthy, term pregnancies and BeWo trophoblasts by density gradient ultracentrifugation. BeWo cells were also tested for their ability to efflux BCRP substrates after treatment with the cholesterol sequestrant methyl-β-cyclodextrin (MβCD, 5 mM, 1 h) or the cholesterol synthesis inhibitor pravastatin (200 μM, 48 h).

RESULTS AND DISCUSSION

BCRP was found to co-localize with lipid raft proteins in detergent-resistant, lipid raft-containing fractions from placental microvillous membranes and BeWo cells. Treatment of BeWo cells with MβCD redistributed BCRP protein into higher density non-lipid raft fractions. Repletion of the cells with cholesterol restored BCRP localization to lipid raft-containing fractions. Treatment of BeWo cells with MβCD or pravastatin increased cellular retention of two BCRP substrates, the fluorescent dye Hoechst 33342 and the mycotoxin zearalenone. Repletion with cholesterol restored BCRP transporter activity. Taken together, these data demonstrate that cholesterol may play a critical role in the post-translational regulation of BCRP in placental lipid rafts.

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.

Effects of a lipid-based nutrient supplement during pregnancy and lactation on maternal plasma fatty acid status and lipid profile: Results of two randomized controlled trials

It is unknown whether a novel small-quantity lipid-based nutrient supplement (SQ-LNS) containing alpha-linolenic (ALA) and linoleic acids impacts maternal plasma lipids and fatty acid status. We measured plasma fatty acids (wt%) and lipid concentrations at 36 wk gestation and breast milk fatty acids (wt%) at 6 months postpartum in a subsample of women enrolled in a randomized controlled trial studying the effects of SQ-LNS on birth outcomes and child growth. Women≤20 wk gestation in Ghana (n=1,320) and Malawi (n=1,391) were assigned to receive daily either: 1) iron-folic acid (pregnancy); 2) multiple micronutrients (pregnancy and lactation); or 3) SQ-LNS (pregnancy and lactation). At 36 wk, plasma ALA levels were higher in those receiving SQ-LNS. SQ-LNS increased breast milk ALA in Ghana but not Malawi. There was no effect on plasma lipids or other selected fatty acids. SQ-LNS may impact plasma and breast milk ALA levels depending on the population.

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.

Spontaneous preterm birth and single nucleotide gene polymorphisms: a recent update

Background

Preterm birth (PTB), birth at <37 weeks of gestation, is a significant global public health problem. World-wide, about 15 million babies are born preterm each year resulting in more than a million deaths of children. Preterm neonates are more prone to problems and need intensive care hospitalization. Health issues may persist through early adulthood and even be carried on to the next generation. Majority (70 %) of PTBs are spontaneous with about a half without any apparent cause and the other half associated with a number of risk factors. Genetic factors are one of the significant risks for PTB. The focus of this review is on single nucleotide gene polymorphisms (SNPs) that are reported to be associated with PTB.

Results

A comprehensive evaluation of studies on SNPs known to confer potential risk of PTB was done by performing a targeted PubMed search for the years 2007–2015 and systematically reviewing all relevant studies. Evaluation of 92 studies identified 119 candidate genes with SNPs that had potential association with PTB. The genes were associated with functions of a wide spectrum of tissue and cell types such as endocrine, tissue remodeling, vascular, metabolic, and immune and inflammatory systems.

Conclusions

A number of potential functional candidate gene variants have been reported that predispose women for PTB. Understanding the complex genomic landscape of PTB needs high-throughput genome sequencing methods such as whole-exome sequencing and whole-genome sequencing approaches that will significantly enhance the understanding of PTB. Identification of high risk women, avoidance of possible risk factors, and provision of personalized health care are important to manage PTB.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-016-3089-0) contains supplementary material, which is available to authorized users.

[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.

Excess weight and dyslipidemia and their complications during pregnancy: a systematic review

Abstract Objectives: to identify bibliographically disorders related to excess weight, dyslipidemia and their complication during pregnancy and in the fetus and newborn. Methods: a systematic review including observational and interventional studies and reviews, based on MEDLINE, LILACS, Embase and the Cochrane Library between 2000 and 2015. The key-words "lipids, pregnancy, obesity and newborn" were used to establish a selective stage for inclusion/exclusion of titles, repeated studies, key-words, abstracts, methodological incompatibility and correlation with objectives. Results: 58 studies were selected, of which 36 (62%) addressed prevention and the risk in pregnancy of excess weight and lipid disorders and 19 (32.7%) suggestions and/or consequences for the fetus and newborn. Conclusions: excess weight and lipidemic disorders in pregnancy are causes for concern in scientific studies, posing risks both for the mother and the newborn. Higher prevalence of caesarian and pre-eclampsia were the two most noteworthy complications for gestational outcomes. In short, the impact on care of maternal habits and excess weight during pregnancy is highly significant, owing to the different degrees of complication in obstetric outcomes and their influence on the clinical characteristics of the newborn.