Physiological adaptation of maternal plasma volume during pregnancy: a systematic review and meta-analysis

Urinary polycyclic aromatic hydrocarbon metabolites in Chinese pregnant women: Concentrations, variability, predictors, and association with oxidative stress biomarkers

Polycyclic aromatic hydrocarbons (PAHs) are a class of pervasive contaminants having adverse health effects. Urinary monohydroxylated PAHs (OH-PAHs) are commonly employed as biomarkers to estimate PAH exposure levels in humans. However, little is understood about the variability in OH-PAHs among pregnant women across trimesters and their relationship with oxidative stress biomarkers (OSBs). Based on a prospective birth cohort study conducted in Wuhan, China, we selected 644 women who donated (spot) urine samples across different trimesters and measured the urinary concentrations of eight OH-PAHs and three selected OSBs (8-OHG, 8-OHdG, and HNEMA) to explore the relationship between the OH-PAHs and OSBs. Pregnant women were found to be ubiquitously exposed to the PAHs, with detection rates of the OH-PAHs ranging from 86.3% to 100%. 2-Hydroxynaphthalene (2-OH-Nap) had the highest urinary concentrations among the OH-PAHs during the three trimesters (specific gravity-adjusted median values for the first, second, and third trimesters: 1.86, 2.39, and 2.20 ng/mL, respectively). However, low reproducibility of the OH-PAHs was observed across the three trimesters with intraclass correlation coefficients ranged between 0.02 and 0.22. Most urinary OH-PAHs had the highest concentrations at the first trimester and the lowest at the third trimester. Some OH-PAH concentrations were higher in pregnant women with lower educational level [2-hydroxyphenanthrene (2-OH-Phen) and 3-hydroxyphenanthrene (3-OH-Phen)], those who were overweight [2-OH-Nap, 2/3-hydroxyfluorene (2/3-OH-Fluo), 2-OH-Phen, and 4-hydroxyphenanthrene (4-OH-Phen)], those who were unemployed during pregnancy [1-hydroxynaphthalene, 1/9-hydroxyphenanthrene, and 4-OH-Phen], and the samples donated in summer (most OH-PAHs, except for 2-OH-Nap). In multivariable linear mixed-effects model analyses, every OH-PAH was found to be significantly associated with increased levels of the three OSBs. For example, each interquartile range-fold increase in 2/3-OH-Fluo concentration was associated with the largest increase in 8-OHdG (65.4%) and 8-OHG (49.1%), while each interquartile range-fold increase in 3-OH-Phen concentration was associated with the largest increase in HNEMA (76.3%). Weighted quantile sum regression models, which were used to examine the joint effect of OH-PAH mixture on the OSBs, revealed positive associations between the OH-PAH mixture exposure and the OSBs. Specifically, 2/3-OH-Fluo and 2-OH-Nap were the major contributors in the association with oxidative damage of nucleic acids (8-OHdG and 8-OHG), while hydroxyphenanthrenes and 1-hydroxypyrene were the major contributors in the association with oxidative damage of lipid (HNEMA). Further work is required to examine the potential mediating role of oxidative stress in the relationship of adverse health outcomes with elevated PAH exposure among pregnant women.

Higher oxygen content and transport characterize high-altitude ethnic Tibetan women with the highest lifetime reproductive success

We chose the "natural laboratory" provided by high-altitude native ethnic Tibetan women who had completed childbearing to examine the hypothesis that multiple oxygen delivery traits were associated with lifetime reproductive success and had genomic associations. Four hundred seventeen (417) women aged 46 to 86 y residing at ≥3,500 m in Upper Mustang, Nepal, provided information on reproductive histories, sociocultural factors, physiological measurements, and DNA samples for this observational cohort study. Simultaneously assessing multiple traits identified combinations associated with lifetime reproductive success measured as the number of livebirths. Women with the most livebirths had distinctive hematological and cardiovascular traits. A hemoglobin concentration near the sample mode and a high percent of oxygen saturation of hemoglobin raised arterial oxygen concentration without risking elevated blood viscosity. We propose ongoing stabilizing selection on hemoglobin concentration because extreme values predicted fewer livebirths and directional selection favoring higher oxygen saturation because higher values had more predicted livebirths. EPAS1, an oxygen homeostasis locus with strong signals of positive natural selection and a high frequency of variants occurring only among populations indigenous to the Tibetan Plateau, associated with hemoglobin concentration. High blood flow into the lungs, wide left ventricles, and low hypoxic heart rate responses aided effective convective oxygen transport to tissues. Women with physiologies closer to unstressed, low altitude values had the highest lifetime reproductive success. This example of ethnic Tibetan women residing at high altitudes in Nepal links reproductive fitness with trait combinations increasing oxygen delivery under severe hypoxic stress and demonstrates ongoing natural selection.

Catheter ablation in a monochorionic diamniotic twin pregnancy: A case report and literature review

RATIONALE

Preexcitation syndrome is an uncommon congenital cardiac disorder that impairs the normal cardiac conduction system. Radiofrequency ablation is one of the most effective treatments for this condition. Nevertheless, radiofrequency ablation is rare in women with preexcitation syndrome during pregnancy.

PATIENT CONCERNS

A 33-year-old woman with monochorionic diamniotic twin pregnancy complicated by sinus arrhythmia with ventricular preexcitation at 14 weeks and 5 days of gestation, with paroxysmal palpitations and shortness of breath at 16 weeks with paroxysmal supraventricular tachycardia with preexcitation syndrome and a heart rate ranging from 180 to 225 beats per minute.

DIAGNOSES

The pregnant occurred sudden palpitations and shortness of breath in the shower. Electrocardiography revealed paroxysmal supraventricular tachycardia, and electrophysiological study revealed preexcitation syndrome (dominant accessory route of the left free wall) with atrioventricular reentrant tachycardia.

INTERVENTIONS

Radiofrequency catheter ablation was performed at 20 weeks.

OUTCOMES

Symptoms of preexcitation syndrome resolved after the radiofrequency catheter ablation, and 2 healthy infants were delivered at 36 weeks and 2 days of gestation by cesarean section.

LESSONS

Preexcitation syndrome may result in life-threatening arrhythmias such as supraventricular tachycardia during pregnancy and delivery. It might be efficiently controlled through optimal treatment by a multidisciplinary team, which would effectively minimize arrhythmia risk events during pregnancy and improve maternal-fetal outcomes. Based on the patient's individual situation, radiofrequency ablation may be a procedure in pregnant women with preexcitation syndrome.

The Fontan Circulation in Pregnancy: Hemodynamic Challenges and Anesthetic Considerations

Pregnancy in patients with Fontan physiology presents unique challenges due to altered cardiovascular dynamics inherent to both conditions. The Fontan procedure reroutes venous blood directly to the pulmonary arteries, bypassing the heart, and necessitating precise regulation of pulmonary venous resistance and systemic venous pressure to maintain effective cardiac output. The significant cardiovascular adaptations required during pregnancy to meet the metabolic demands of the mother and fetus can overburden the limited preload capacity and venous compliance in Fontan patients, predisposing them to a spectrum of potential complications, including arrhythmias, heart failure, thromboembolism, and obstetric and fetal risks. This review delineates the essential physiological adaptations during pregnancy and the challenges faced by Fontan patients, advocating for a comprehensive care approach involving multidisciplinary collaboration, vigilant monitoring, tailored anesthetic management, and postpartum care. Understanding the complex dynamics between Fontan physiology and pregnancy is crucial for anesthesiologists to develop and execute individualized management strategies to minimize risks and optimize outcomes for this high-risk population.

The association between first trimester blood pressure, blood pressure trajectory, mid-pregnancy blood pressure drop and maternal and fetal outcomes: A systematic review and meta-analysis

BACKGROUND

Hypertensive disorders of pregnancy occur in 5-10 % of pregnancies and are associated with an increased risk of adverse perinatal outcomes.

OBJECTIVES

This review investigates the association between first trimester blood pressure (BP), mid-pregnancy BP drop, and BP-trajectories during pregnancy and adverse perinatal outcomes, exploring the fit of prediction and prevention.

SEARCH STRATEGY

Observational studies published before September 2023, reporting on desired determinants of BP and outcomes (preeclampsia (PE), severe hypertension, small for gestational age (SGA), fetal growth restriction (FGR)) were identified in MEDLINE, Embase and Cochrane.

DATA COLLECTION AND ANALYSIS

Data were collected in Excel. Results were analysed per BP-determinant. Meta analysis was performed for first trimester BP.

MAIN RESULTS

Ten studies met selection criteria. A great variety of cut-off values were used for BP categorization. Pooled analysis of 6 studies showed that women with borderline or hypertensive first trimester BP had a higher risk of PE compared to normotensive BP, OR 3.23 (95 % CI 1.99-5.26) and 7.86 (95 % CI 1.28-48.31), respectively. Additionally, first trimester hypertension correlated with a higher risk of SGA neonate (pooled OR of 1.87 (95 % CI 1.17-2.99)) compared to normotension or borderline hypertension. Throughout pregnancy, prehypertension, hypertension, elevated and high stable trajectories increased PE risk. High-stable trajectory increased SGA neonate risk.

CONCLUSIONS

The findings suggest that women with borderline and hypertensive BP in the first trimester are at increased risk for PE and SGA. However, standardization of cut-off values and BP measurement is necessary to estimate outcome risks more accurately.

Chronic cold exposure causes left ventricular hypertrophy that appears to be physiological

Exposure to winter cold causes an increase in energy demands to meet the challenge of thermoregulation. In small rodents, this increase in cardiac output leads to a profound cardiac hypertrophy, 2-3 times that typically seen with exercise training. The nature of this hypertrophy and its relevance to winter mortality remains unclear. Our goal was to characterize cold-induced cardiac hypertrophy and to assess its similarity to either exercise-induced (physiological) hypertrophy or the pathological hypertrophy of hypertension. We hypothesized that cold-induced hypertrophy will most closely resemble exercise-induced hypertrophy, but be another unique pathway for physiological cardiac growth. We found that cold-induced hypertrophy was largely reversed after a return to warm temperatures. Further, metabolic rates were elevated while gene expression and mitochondrial enzyme activities indicative of pathology were absent. A gene expression panel comparing hearts of exercised and cold-exposed mice further suggests that these activities are similar, although not identical. In conclusion, we found that chronic cold led to a phenotype that most closely resembled physiological hypertrophy, with enhanced metabolic rate, without induction of fetal genes, but with decreased expression of genes associated with fatty acid oxidation, suggesting that heart failure is not a cause of winter mortality in small rodents and identifying a novel approach for the study of cardiac growth.

Maternal hemoglobin drop in multiple pregnancy is associated with higher gestational age at birth and birthweight

INTRODUCTION

This retrospective study investigated the hypothesis that maternal hemoglobin (Hb) levels in twin pregnancy fall between the first and second trimesters and that higher falls are associated with higher gestational age at birth and higher birthweight (BW).

MATERIAL AND METHODS

The study population was defined as pregnant women with twin pregnancies delivering two live, phenotypically normal neonates, after 24+0 weeks of gestation, between October 2009 and September 2021 at an inner London maternity unit. Maternal Hb and mean corpuscular volume (MCV), at ≤14+0 weeks of gestation (Hb1) and again at 20+0-30+0 weeks gestation (Hb2) were recorded from the Hospital's perinatal database. MCV was used as a possible indicator of iron deficiency anemia. The association of Hb drop, defined as [Hb1(adjusted for gestational age) - Hb2], and MCV values with gestational age at birth, BW of both twins and delivery of small for gestational age (SGA) neonates, defined as BW <10th percentile for gestation, was evaluated.

RESULTS

923 pregnant women with twin pregnancies were included. Maternal Hb1 did not correlate with any outcomes measured. However, a lower Hb2 and a larger Hb drop was associated with a higher gestational age at birth (p < 0.001), a larger BW of twin 1 and 2 (p < 0.001 for both) and a reduction in the incidence of delivering one or two SGA neonates (p < 0.001 for both). MCV values did not correlate significantly with these outcomes.

CONCLUSIONS

This study showed that in twin pregnancy, a larger maternal Hb drop from the first to the second trimester is associated with a higher gestational age at birth and a larger BW. This change may represent a larger plasma volume expansion.

Fluid resuscitation strategy in patients with placenta previa accreta: a retrospective study

Objectives

Obstetric hemorrhage is the leading cause of maternal death worldwide. Placenta previa accreta is one of the major direct causes of postpartum hemorrhage, accounting for two-thirds of obstetric hemorrhage cases. Fluid resuscitation is a life-saving procedure for patients suffering from massive hemorrhage. This study aims at evaluating the risk factors of massive hemorrhage and appropriate fluid resuscitation strategy in patients with placenta previa accreta.

Methods

This study retrospectively analyzed the risk factors for massive hemorrhage, clinical characteristics, and perinatal outcomes of patients with placenta previa accreta. Maternal noninvasively evaluated hemodynamic indicators, including maternal heart rate, systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), and shock index, were collected and analyzed at nine time points, from the administration of anesthesia until the end of procedures, in patients diagnosed with placenta previa accreta and receiving different fluid supply volumes.

Results

Complicated with placenta increta/percreta and gestational age of delivery later than 37 weeks are two independent risk factors of massive hemorrhage in patients with placenta previa accreta. A total of 62.27% (170/273) patients diagnosed with placenta increta/percreta had massive hemorrhage, significantly higher than those diagnosed with placenta previa accreta (5.88%, 6/102). Patients delivered after 37 weeks of gestation had significantly higher ratios (86.84%, 99/114) of massive hemorrhage compared with those delivered between 36 and 36+6 weeks of gestation (35.39%, 63/178). Maternal SBP, DBP, and MAP started to decrease immediately after the baby was delivered and reached a relatively stable trough state at 15-30 min after delivery. No statistical differences were found in hemodynamic indicators, the occurrence of hypotension, or in-hospital days after the procedure among the transfusion volumes < 30 ml/kg, 30-80 ml/kg, and ≥ 80 ml/kg groups.

Conclusion

Patients with a suspected diagnosis of placenta previa accreta should plan to deliver before 37 weeks of gestation. The ability to identify concurrent placenta increta/percreta should be improved to schedule a reasonably rapid perioperative plan. Restrictive fluid resuscitation could achieve good effects in maintaining hemodynamic stability in patients with placenta previa accreta. A time period of 15-30 min after delivery is the critical stage for fluid resuscitation.

Fibroblast growth factor 21

Fibroblast growth factor 21 (FGF21) belongs to the FGF19 subfamily and acts systemically, playing a key role in inter-organ crosstalk. Ranging from metabolism, reproduction, and immunity, FGF21 is a pleiotropic hormone which contributes to various physiological processes. Although most of its production across species stems from hepatic tissues, expression of FGF21 in mice has also been identified in adipose tissue, thymus, heart, pancreas, and skeletal muscle. Elevated FGF21 levels are affiliated with various diseases and conditions, such as obesity, type 2 diabetes, preeclampsia, as well as cancer. Murine knockout models are viable and show modest weight gain, while overexpression and gain-of-function models display resistance to weight gain, altered bone volume, and enhanced immunity. In addition, FGF21-based therapies are at the forefront of biopharmaceutical strategies aimed at treating metabolic dysfunction-associated steatotic liver disease.

Number of Pregnancies and Risk of Atherosclerotic Cardiovascular Disease in Postmenopausal Women: A Cross-Sectional Study of NHANES from 1999 to 2018

Background: Atherosclerotic cardiovascular disease (ASCVD) remains the most common cause of death in women. Pregnancy is an exposure unique to women leading to significant changes in maternal cardiovascular function. However, studies of the relationship between the number of pregnancies and ASCVD are rare. We aimed to clarify the association between the number of pregnancies and ASCVD. Methods: In this cross-sectional study, we used publicly available data from the National Health and Nutrition Examination Survey from 1999 to 2018. The number of pregnancies was divided into 0 (reference), 1, 2-3, 4-5, or ≥6, to create more stable estimates. A multiple logistic regression approach was used to examine the correlation between pregnancy and ASCVD in women aged 45 years or older who reported no menstruation in the past 12 months due to menopause, as well as in those aged 55 years or older, encompassing various age groups. We also separately estimated the association between the exposure of pregnancy and individual components of ASCVD. Results: In this study, age-adjusted data showed that women with six or more pregnancies had a doubled risk (odds ratio [OR]: 2.07) of ASCVD. The risk remained elevated at 1.69 times in women with four to five pregnancies and further increased to 1.90 times in women with six or more pregnancies, after adjusting for social factors. Similar patterns were observed when considering reproductive health and cardiovascular risk factors. Across the full population, every model that accounted for these variables consistently indicated that with an increasing number of pregnancies, we observed higher ORs for ASCVD risk (all p values <0.05). Conclusions: A higher number of pregnancies was associated with a higher risk of ASCVD after menopause, especially among women aged 45-64 years. Moreover, this association is particularly significant in the risk of stroke, cardiovascular heart disease, and heart attack.

Guidelines for assessing maternal cardiovascular physiology during pregnancy and postpartum

Maternal mortality rates are at an all-time high across the world and are set to increase in subsequent years. Cardiovascular disease is the leading cause of death during pregnancy and postpartum, especially in the United States. Therefore, understanding the physiological changes in the cardiovascular system during normal pregnancy is necessary to understand disease-related pathology. Significant systemic and cardiovascular physiological changes occur during pregnancy that are essential for supporting the maternal-fetal dyad. The physiological impact of pregnancy on the cardiovascular system has been examined in both experimental animal models and in humans. However, there is a continued need in this field of study to provide increased rigor and reproducibility. Therefore, these guidelines aim to provide information regarding best practices and recommendations to accurately and rigorously measure cardiovascular physiology during normal and cardiovascular disease-complicated pregnancies in human and animal models.

The association between PM2.5 components and blood pressure changes in late pregnancy: A combined analysis of traditional and machine learning models

BACKGROUND

PM2.5 is a harmful mixture of various chemical components that pose a challenge in determining their individual and combined health effects due to multicollinearity issues with traditional linear regression models. This study aimed to develop an analytical methodology combining traditional and novel machine learning models to evaluate PM2.5's combined effects on blood pressure (BP) and identify the most toxic components.

METHODS

We measured late-pregnancy BP of 1138 women from the Heshan cohort while simultaneously analyzing 31 PM2.5 components. We utilized multiple linear regression modeling to establish the relationship between PM2.5 components and late-pregnancy BP and applied Random Forest (RF) and generalized Weighted Quantile Sum (gWQS) regression to identify the most toxic components contributing to elevated BP and to quantitatively evaluate the cumulative effect of the PM2.5 component mixtures.

RESULTS

The results revealed that 16 PM2.5 components, such as EC, OC, Ti, Fe, Mn, Cu, Cd, Mg, K, Pb, Se, Na+, K+, Cl-, NO3-, and F-, contributed to elevated systolic blood pressure (SBP), while 26 components, including two carbon components (EC, OC), fourteen metallics (Ti, Fe, Mn, Cr, Mo, Co, Cu, Zn, Cd, Na, Mg, Al, K, Pb), one metalloid (Se), and nine water-soluble ions (Na+, K+, Mg2+, Ca2+, NH4+, Cl-, NO3-, SO42-, F-), contributed to elevated diastolic blood pressure (DBP). Mn and Cr were the most toxic components for elevated SBP and DBP, respectively, as analyzed by RF and gWQS models and verified against each other. Exposure to PM2.5 component mixtures increased SBP by 1.04 mmHg (95% CI: 0.33-1.76) and DBP by 1.13 mmHg (95% CI: 0.47-1.78).

CONCLUSIONS

Our study highlights the effectiveness of combining traditional and novel models as an analytical strategy to quantify the health effects of PM2.5 constituent mixtures.

Multiple Infections, Nutrient Deficiencies, and Inflammation as Determinants of Anemia and Iron Status during Pregnancy: The MINDI Cohort

In pregnant women with multiple infections, nutrient deficiencies, and inflammation (MINDI), the study of anemia and iron status is limited. For this cross-sectional study (n = 213 Panamanian indigenous women), we investigated if hemoglobin, anemia (Hb < 110 g/L), ferritin, serum iron, serum transferrin receptor, and hepcidin were associated with (1) maternal nutritional status and supplementation practices, (2) biomarkers of inflammation, and (3) presence/absence of infections. Hierarchical generalized linear and logistic regression models and dominance analyses identified the relative importance of these predictors. Anemia (38%), which was likely underestimated due to low plasma volume (95%), was associated with lower ferritin, vitamin A, and weight-for-height, suggesting anemia of undernutrition. Inflammation was not associated with Hb or anemia; nevertheless, higher CRP was associated with increased odds of low serum iron and higher ferritin and hepcidin, indicating iron restriction due to inflammation. The length of iron supplementation did not enter models for anemia or iron indicators, but a multiple nutrient supplement was associated with higher ferritin and hepcidin. Moreover, iron supplementation was associated with higher odds of vaginal trichomoniasis but lower odds of caries and bacterial vaginosis. The complex pathogenesis of anemia and iron deficiency in MINDI settings may require other interventions beyond iron supplementation.

Biomarker Candidates of Habitual Food Intake in a Swedish Cohort of Pregnant and Lactating Women and Their Infants

Circulating food metabolites could improve dietary assessments by complementing traditional methods. Here, biomarker candidates of food intake were identified in plasma samples from pregnancy (gestational week 29, N = 579), delivery (mothers, N = 532; infants, N = 348), and four months postpartum (mothers, N = 477; breastfed infants, N = 193) and associated to food intake assessed with semi-quantitative food frequency questionnaires. Families from the Swedish birth cohort Nutritional impact on Immunological maturation during Childhood in relation to the Environment (NICE) were included. Samples were analyzed using untargeted liquid chromatography-mass spectrometry (LC-MS)-based metabolomics. Both exposure and outcome were standardized, and relationships were investigated using a linear regression analysis. The intake of fruits and berries and fruit juice were both positively related to proline betaine levels during pregnancy (fruits and berries, β = 0.23, FDR < 0.001; fruit juice, β = 0.27, FDR < 0.001), at delivery (fruit juice, infants: β = 0.19, FDR = 0.028), and postpartum (fruits and berries, mothers: β = 0.27, FDR < 0.001, infants: β = 0.29, FDR < 0.001; fruit juice, mothers: β = 0.37, FDR < 0.001). Lutein levels were positively related to vegetable intake during pregnancy (β = 0.23, FDR < 0.001) and delivery (mothers: β = 0.24, FDR < 0.001; newborns: β = 0.18, FDR = 0.014) and CMPF with fatty fish intake postpartum (mothers: β = 0.20, FDR < 0.001). No clear relationships were observed with the expected food sources of the remaining metabolites (acetylcarnitine, choline, indole-3-lactic acid, pipecolic acid). Our study suggests that plasma lutein could be useful as a more general food group intake biomarker for vegetables and fruits during pregnancy and delivery. Also, our results suggest the application of proline betaine as an intake biomarker of citrus fruit during gestation and lactation.

Active plasma renin concentration throughout healthy and complicated pregnancy: a systematic review and meta-analysis

BACKGROUND

Pregnancy is characterized by profound circulatory changes and compensatory adjustments in the renin-angiotensin-aldosterone system (RAAS). Differences in regulatory response may antedate or accompany vascular complicated pregnancy. We performed a systematic review and meta-analysis to delineate the trajectory of active plasma renin concentration (APRC) in healthy pregnancy and compare this to complicated pregnancy.

METHODS

We performed a systematic review and meta-analysis on APRC during normotensive and hypertensive pregnancies, using PubMed (NCBI) and Embase (Ovid) databases. We included only studies reporting measurements during pregnancy together with a nonpregnant reference group measurement. Risk of bias was assessed with QUIPS. Ratio of the mean (ROM) and 95% confidence intervals (CI) of APRC values between pregnant and nonpregnant women were estimated for predefined intervals of gestational age using a random-effects model. Meta-regression was used to analyze APRC over time.

RESULTS

In total, we included 18 studies. As compared to nonpregnant, APRC significantly increased as early as the first weeks of healthy pregnancy and stayed increased throughout the whole pregnancy (ROM 2.77; 95% CI 2.26-3.39). APRC in hypertensive complicated pregnancy was not significantly different from nonpregnancy (ROM 1.32; 95% CI 0.97-1.80).

CONCLUSION

Healthy pregnancy is accompanied by a profound rise in APRC in the first trimester that is maintained until term. In hypertensive complicated pregnancy, this increase in APRC is not observed.

Ventricular Tachycardia in Patients With Pre-eclampsia: Prevalence, Predictors, and Associated In-Hospital Adverse Events

Introduction Pre-eclampsia is a pregnancy-associated multisystem disorder; in rare cases, it can be complicated by arrhythmias such as ventricular tachycardia (VT). The purpose of this study was to determine the prevalence and predictors of VT among patients admitted with pre-eclampsia as well as to analyze the independent association of VT with in-hospital outcomes in this population. Methods Data were obtained from the National Inpatient Sample from January 2016 to December 2019. Patients with a primary diagnosis of pre-eclampsia were selected using International Classification of Diseases, 10th Revision, Clinical Modification (ICD-10-CM) codes. Subsequently, the study population was divided into patients who developed VT versus patients who did not develop this complication. We then assessed the predictors of VT in women with pre-eclampsia as well as the independent association of VT with outcomes taking into account confounders such as age, race, and comorbidities. Results Of 255,946 patients with pre-eclampsia, 92 developed VT (0.04%) during their hospital stay. Multivariate logistic regression showed that patients with VT were far more likely to develop cardiac arrest (adjusted odds ratio, or aOR: 92.582, 95% CI: 30.958-276.871, p=0.001), require permanent pacemaker implantation (aOR: 41.866, 95% CI: 14.800-118.432, p=0.001), develop postpartum hemorrhage (aOR: 2.932, 95% CI: 1.655-5.196, p=0.001), and require left heart catheterization (aOR: 19.508, 95% CI: 3.261-116.708, p=0.001). Predictors of VT included being African American (aOR: 1.939, 95% CI: 1.183-3.177, p=0.009), cerebrovascular disease (aOR: 23.109, 95% CI: 6.953-76.802, p=0.001), congestive heart failure (aOR: 50.340, 95% CI: 28.829-87.901, p=0.001), atrial fibrillation (aOR: 20.148, 95% CI: 6.179-65.690, p=0.001), and obstructive sleep apnea, or OSA (aOR: 3.951, 95% CI: 1.486-10.505, p=0.006). Patients in the VT cohort were found to have an increased length of hospital stay compared to the non-VT cohort (7.16 vs. 4.13 days, p=0.001). Conclusion In a large cohort of women admitted with pre-eclampsia, we found the prevalence of VT to be <1%. Predictors of VT included conditions such as atrial fibrillation, congestive heart failure, and OSA and being African American. VT was found to be independently associated with several adverse outcomes as well as an increased length of hospital stay.

Neglected medium-term and long-term consequences of labour and childbirth: a systematic analysis of the burden, recommended practices, and a way forward

Over the past three decades, substantial progress has been made in reducing maternal mortality worldwide. However, the historical focus on mortality reduction has been accompanied by comparative neglect of labour and birth complications that can emerge or persist months or years postnatally. This paper addresses these overlooked conditions, arguing that their absence from the global health agenda and national action plans has led to the misconception that they are uncommon or unimportant. The historical limitation of postnatal care services to the 6 weeks after birth is also a contributing factor. We reviewed epidemiological data on medium-term and long-term complications arising from labour and childbirth beyond 6 weeks, along with high-quality clinical guidelines for their prevention, identification, and treatment. We explore the complex interplay of human evolution, maternal physiology, and inherent predispositions that contribute to these complications. We offer actionable recommendations to change the current trajectories of these neglected conditions and help achieve the targets of Sustainable Development Goal 3. This paper is the third in a Series of four papers about maternal health in the perinatal period and beyond.

Identification and treatment of iron-deficiency anemia in pregnancy and postpartum: A systematic review and quality appraisal of guidelines using AGREE II

BACKGROUND

Several international guidelines provide recommendations for the optimal management of iron-deficiency anemia (IDA) in the pregnant and postpartum populations.

OBJECTIVES

To review the quality of guidelines containing recommendations for the identification and treatment of IDA in pregnancy and postpartum using the Appraisal of Guidelines for Research and Evaluation II (AGREE II) instrument and to summarize their recommendations.

SEARCH STRATEGY

PubMed, Medline, and Embase databases were searched from inception to August 2, 2021. A web engine search was also performed.

SELECTION CRITERIA

Clinical practice guidelines that focused on the management of IDA in pregnancy and/or postpartum populations were included.

DATA COLLECTION AND ANALYSIS

Included guidelines were appraised using AGREE II independently by two reviewers. Domain scores greater than 70% were considered high-quality. Overall scores of six or seven (out of a possible seven) were considered high-quality guidelines. Recommendations on IDA management were extracted and summarized.

MAIN RESULTS

Of 2887 citations, 16 guidelines were included. Only six (37.5%) guidelines were deemed high-quality and were recommended by the reviewers. All 16 (100%) guidelines discussed the management of IDA in pregnancy, and 10 (62.5%) also included information on the management of IDA in the postpartum period.

CONCLUSIONS

The complex interplay of racial, ethnic, and socioeconomic disparities was rarely addressed, which limits the generalizability of the recommendations. In addition, many guidelines failed to identify barriers to implementation, strategies to improve uptake or iron treatment, and resource and cost implications of clinical recommendations. These findings highlight important areas to target future work.

Maternal anaemia during early pregnancy and the risk of neonatal outcomes: a prospective cohort study in Central China

BACKGROUND

The purpose of this study was to explore the association between anaemia during early pregnancy and the risk of neonatal outcomes.

METHODS

We collected clinical data from pregnant women (≥18 years) who received their first antenatal care between 8 and 14 weeks of gestation in Hunan Provincial Maternal and Child Health Care Hospital. Multiple logistic regression models and restricted cubic spline regression models were used to analyse the association between anaemia during early pregnancy and the risk of neonatal outcomes. In addition, sensitivity analysis was further performed to assess the robustness of the results.

RESULTS

The prospective cohort study ultimately included 34 087 singleton pregnancies. In this study, the rate of anaemia during early pregnancy was 16.3%. Our data showed that there was a positive relationship between the rate of preterm birth, low birth weight as well as small for gestational age (SGA) and the severity of maternal anaemia (Ptrend<0.05). After adjustment, the association of early pregnancy anaemia and haemoglobin (Hb) levels with the risk of preterm birth (mild anaemia adjusted OR (aOR) 1.37 (95% CI 1.25 to 1.52), moderate anaemia aOR 1.54 (95% CI 1.35 to 1.76) and severe anaemia aOR 4.03 (95% CI 2.67 to 6.08), respectively), low birth weight (mild anaemia aOR 1.61 (95% CI 1.44 to 1.79), moderate anaemia aOR 2.01 (95% CI 1.75 to 2.30) and severe anaemia aOR 6.11 (95% CI 3.99 to 9.36), respectively) and SGA (mild anaemia aOR 1.37 (95% CI 1.25 to 1.52), moderate anaemia aOR 1.54 (95% CI 1.35 to 1.76) and severe anaemia aOR 2.61 (95% CI 1.74 to 4.50), respectively; Pnon-linear<0.05) was observed. However, no association was found between early pregnancy anaemia or Hb levels and the risk of congenital malformations. Sensitivity analysis verified the stability of the results.

CONCLUSIONS

Maternal anaemia during early pregnancy was associated with an increased risk of preterm birth, low birth weight and SGA and their rates may increase with the severity of maternal anaemia.

TRIAL REGISTRATION NUMBER

ChiCTR1800016635.

PCSK9 inhibitor use during pregnancy in a case of familial hypercholesterolemia complicated with coronary artery disease

Limited data have been reported on the use of proprotein convertase subtilisin/kexin type 9 (PCSK 9) inhibitors during pregnancy in women with familial hypercholesterolemia (FH). Here, we present the first case of initiating evolocumab (PCSK9 inhibitor) in a compound heterozygous FH mother. The patient was a 34-year-old primipara with severe dyslipidemia and a history of coronary artery bypass surgery. An elevated low-density lipoprotein cholesterol (LDL-C) level of 420 mg/dL was detected in the first trimester and persistently increased throughout pregnancy. Evolocumab was administered at 31 and 35 weeks of gestation, showing a positive effect on stabilizing LDL-C levels. Planned delivery with labor analgesia was performed at 38 + 4 weeks. Both the mother and infant were discharged without any notable complications. Hence, evolocumab, an IgG2 monochromatic antibody with little placental permeability, may be an alternative medication with limited influence on infants. Further studies are needed to assess the safety of evolocumab administration during pregnancy.

Effect of Third Interstitial Fluid on Adverse Outcomes in Patients with Severe Pre-eclampsia and Twin Pregnancy: A 5-year Single-center Retrospective Study

OBJECTIVE

This study aims to identify the effect of third interstitial fluid on adverse outcomes in twin pregnancies with severe pre-eclampsia, and explore the differences in bad ending between twins and singletons.

METHODS

The present retrospective cohort study was conducted on patients with severe pre-eclampsia, who delivered in Tongji Hospital, Wuhan, China, between 2017 and 2022. The adverse outcomes in singleton and twin pregnancies with severe pre-eclampsia were initially investigated. Then, the diverse maternal and fetal consequences between singleton and twin pregnancies in patients with severe pre-eclampsia were compared after merging with the third interstitial fluid.

RESULTS

A total of 709 patients were included for the present study. Among these patients, 68 patients had twin pregnancies, and 641 patients had singleton pregnancies. The rate of postpartum hemorrhage (2.81% vs. 13.24%, P<0.001), and admission rate to the Neonatal Intensive Care Unit (NICU) after birth (30.73% vs. 63.24%, P=0.011) were significantly higher in twin pregnancies. The neonatal weight of twins was statistically lower than singletons (1964.73±510.61 g vs. 2142.92±731.25 g, P=0.008). For the groups with the third interstitial fluid, the delivery week (P=0.001) and rate of admission to the NICU after birth were significantly advanced in twin pregnancy group, when compared to singleton pregnancy group (P=0.032), and the length of hospital stay was shorter (P=0.044). Furthermore, there was no statistically significant difference between the twin pregnancy group and the singletony pregnancy group without the third interstitial fluid.

CONCLUSION

The maternal and fetal adverse outcomes of patients with severe pre-eclampsia increased in twin pregnancies, when compared to singleton pregnancies. Thus, when patients develop the third interstitial fluid, twin pregnancies would more likely lead to adverse fetal outcomes, when compared to singleton pregnancies, and there would be no significant difference in maternal adverse outcomes. More attention should be given to patients who merge with the third interstitial fluid.

The Amount of Fluid Intake among Pregnant Women in China Increases with Pregnancy Progression: A Prospective Cohort Study

Fluid intake and hydration status during pregnancy may have influences on maternal and infant health. However, few studies have recorded and analyzed total fluid intake (TFI) levels during the whole pregnancy. This study mainly aimed to investigate the TFI levels of pregnant women in three trimesters, and further to assess their hydration status. The relationships of TFI and hydration status were also analyzed. A convenience sampling method was used to recruit pregnant women from the Haikou Maternity and Child Health Hospital in China in this prospective cohort study. A 7-day 24 h fluid intake questionnaire was used for recording the fluid intake of the participants in their three trimesters. Fasting blood samples and first morning urine samples were also collected and tested. Hydration status was evaluated using urine osmolality. Finally, 142 pregnant women completed the study. The median TFIs in the first, second, and third trimesters were 1336, 1477, and 1584 mL, respectively. The TFI levels increased with pregnancy progression (χ2 = 134.155, p < 0.05). Out of 142 participants, 100.0%, 97.2%, and 85.2% of participants did not reach the recommendation amount for an adequate TFI among Chinese pregnant women in the three trimesters, respectively (χ2 = 29.840, p < 0.05). Plain water was the main source of fluid intake, accounting for 92.0%, 94.2%, and 93.4% of TFI, respectively. The median values of dairy product intake were 61, 57, and 59 mL in the three trimesters. The frequency of participants without an optimal hydration status in the three trimesters was 71.8%, 76.1%, and 83.1%, respectively (χ2 = 29.909, p < 0.05). The participants of each trimester were divided into four groups according to quartiles of TFI, including participants with a lower fluid intake (LFI1 and LFI2) and higher fluid intake (HFI1 and HFI2). As the TFI values increased from the LFI1 group to the HFI2 group, the urine osmolality decreased (all p < 0.05). Moderate-intensity negative correlations were found between urine osmolality, hydration status, and TFI (all p < 0.05). It is suggested that fluid intake strategies should be promoted and health education should be conducted to improve the hydration status of pregnant women.

The Association Between Serum Magnesium Levels and Gestational Diabetes Mellitus: a Systematic Review and Meta-Analysis

Observational studies suggest that the potential role of magnesium remains controversial in gestational diabetes mellitus (GDM). This meta-analysis aims to consolidate the available information from observational studies that have focused on the relationship between magnesium levels and GDM. A systematic and comprehensive literature search was conducted in PubMed, Embase, Web of Science, CNKI, and Wanfang databases. Data were extracted independently by two investigators. Standardized mean differences (SMD) and 95% confidence intervals (CIs) were used to summarize the circulating magnesium levels (CI). This meta-analysis included a total of 17 studies involving 2858 participants including 1404 GDM cases and 1454 healthy controls, which showed that magnesium levels were significantly lower in GDM compared to healthy controls (SMD: - 0.35; 95% CI: - 0.62, - 0.07, P = 0.013). Likewise, the same phenomenon was observed in the third trimester (SMD =  - 1.07; 95% CI: - 1.84 to - 0.29, P = 0.007). Other subgroup analyses revealed that this trend of decreasing magnesium concentration was only observed in Europeans (SMD =  - 0.64; 95% CI: - 0.90, - 0.38, P < 0.0001). This meta-analysis revealed that serum magnesium levels were lower in patients with GDM than in healthy pregnant women, and this discrepancy was most pronounced in European populations and during the third trimester. Nevertheless, current evidence suggests that circulating magnesium deficiency is associated with gestational diabetes; the challenge for the future is to further elucidate the possible benefits of preventing gestational diabetes through magnesium supplementation.

Evaluation and Management of Hypertensive Disorders of Pregnancy

Hypertensive disorders of pregnancy complicate up to 10% of pregnancies and remain the major cause of maternal and neonatal morbidity and mortality. Hypertensive disorders of pregnancy can be classified into four groups depending on the onset of hypertension and the presence of target organ involvement: chronic hypertension, preeclampsia, gestational hypertension, and superimposed preeclampsia on chronic hypertension. Hypertension during pregnancy is associated with a higher risk of cardiovascular disease and kidney failure. Early diagnosis and proper treatment for pregnant women with hypertension remain a priority since this leads to improved maternal and fetal outcomes. Labetalol, nifedipine, methyldopa, and hydralazine are the preferred medications to treat hypertension during pregnancy. In this comprehensive review, we discuss the diagnostic criteria, evaluation, and management of pregnant women with hypertension.

Elevated levels of renal function tests conferred increased risks of developing various pregnancy complications and adverse perinatal outcomes: insights from a population-based cohort study

OBJECTIVES

Physiological changes during pregnancy can affect the results of renal function tests (RFTs). In this population-based cohort study, we aimed to establish trimester-specific reference intervals (RIs) of RFTs in singleton and twin pregnancies and systematically investigate the relationship between RFTs and adverse pregnancy outcomes.

METHODS

The laboratory results of the first- and third-trimester RFTs, including blood urea nitrogen (BUN), serum uric acid (UA), creatinine (Crea) and cystatin C (Cys C), and the relevant medical records, were retrieved from 29,328 singleton and 840 twin pregnant women who underwent antenatal examinations from November 20, 2017 to January 31, 2021. The trimester-specific RIs of RFTs were estimated with both of the direct observational and the indirect Hoffmann methods. The associations between RTFs and pregnancy complications as well as perinatal outcomes were assessed by logistic regression analysis.

RESULTS

Maternal RFTs showed no significant difference between the direct RIs established with healthy pregnant women and the calculated RIs derived from the Hoffmann method. In addition, elevated levels of RFTs were associated with increased risks of developing various pregnancy complications and adverse perinatal outcomes. Notably, elevated third-trimester RFTs posed strong risks of preterm birth (PTB) and fetal growth restriction (FGR).

CONCLUSIONS

We established the trimester-specific RIs of RFTs in both singleton and twin pregnancies. Our risk analysis findings underscored the importance of RFTs in identifying women at high risks of developing adverse complications or outcomes during pregnancy.

Made in the Womb: Maternal Programming of Offspring Cardiovascular Function by an Obesogenic Womb

Obesity incidence has been increasing at an alarming rate, especially in women of reproductive age. It is estimated that 50% of pregnancies occur in overweight or obese women. It has been described that maternal obesity (MO) predisposes the offspring to an increased risk of developing many chronic diseases in an early stage of life, including obesity, type 2 diabetes, and cardiovascular disease (CVD). CVD is the main cause of death worldwide among men and women, and it is manifested in a sex-divergent way. Maternal nutrition and MO during gestation could prompt CVD development in the offspring through adaptations of the offspring's cardiovascular system in the womb, including cardiac epigenetic and persistent metabolic programming of signaling pathways and modulation of mitochondrial metabolic function. Currently, despite diet supplementation, effective therapeutical solutions to prevent the deleterious cardiac offspring function programming by an obesogenic womb are lacking. In this review, we discuss the mechanisms by which an obesogenic intrauterine environment could program the offspring's cardiovascular metabolism in a sex-divergent way, with a special focus on cardiac mitochondrial function, and debate possible strategies to implement during MO pregnancy that could ameliorate, revert, or even prevent deleterious effects of MO on the offspring's cardiovascular system. The impact of maternal physical exercise during an obesogenic pregnancy, nutritional interventions, and supplementation on offspring's cardiac metabolism are discussed, highlighting changes that may be favorable to MO offspring's cardiovascular health, which might result in the attenuation or even prevention of the development of CVD in MO offspring. The objectives of this manuscript are to comprehensively examine the various aspects of MO during pregnancy and explore the underlying mechanisms that contribute to an increased CVD risk in the offspring. We review the current literature on MO and its impact on the offspring's cardiometabolic health. Furthermore, we discuss the potential long-term consequences for the offspring. Understanding the multifaceted effects of MO on the offspring's health is crucial for healthcare providers, researchers, and policymakers to develop effective strategies for prevention and intervention to improve care.

The impact of recommending iron supplements to women with depleted iron stores in early pregnancy on use of supplements, and factors associated with changes in iron status from early pregnancy to postpartum in a multi-ethnic population-based cohort

BACKGROUND

We aimed to evaluate the impact of recommending supplementation to pregnant women with serum ferritin (SF) < 20 µg/L in early pregnancy on use of supplements, and to explore which factors were associated with changes in iron status by different iron indicators to 14 weeks postpartum.

METHODS

A multi-ethnic population-based cohort study of 573 pregnant women examined at mean gestational week (GW) 15 (enrolment), at mean GW 28 and at the postpartum visit (mean 14 weeks after delivery). Women with SF < 20 µg/L at enrolment were recommended 30-50 mg iron supplementation and supplement use was assessed at all visits. Change of SF, soluble transferrin receptor and total body iron from enrolment to postpartum were calculated by subtracting the concentrations at the postpartum visit from that at enrolment. Linear and logistic regression analyses were performed to assess associations between use of supplements in GW 28 and changes in iron status and postpartum iron deficiency/anaemia. Change of iron status was categorized into 'steady low', 'improvement', 'deterioration', and 'steady high' based on SF status at enrolment and postpartum. Multinomial logistic regression analyses were performed to identify factors associated with change of iron status.

RESULTS

At enrolment, 44% had SF < 20 µg/L. Among these women (78% non-Western European origin), use of supplements increased from 25% (enrolment) to 65% (GW 28). Use of supplements in GW 28 was associated with improved iron levels by all three indicators (p < 0.05) and with haemoglobin concentration (p < 0.001) from enrolment to postpartum, and with lower odds of postpartum iron deficiency by SF and TBI (p < 0.05). Factors positively associated with 'steady low' were: use of supplements, postpartum haemorrhage, an unhealthy dietary pattern and South Asian ethnicity (p ≤ 0.01 for all); with 'deterioration': postpartum haemorrhage, an unhealthy dietary pattern, primiparity and no use of supplements (p < 0.01 for all), and with 'improvement': use of supplements, multiparity and South Asian ethnicity (p < 0.03 for all).

CONCLUSIONS

Both supplement use and iron status improved from enrolment to the postpartum visit among women recommended supplementation. Dietary pattern, use of supplements, ethnicity, parity and postpartum haemorrhage were identified as factors associated with change in iron status.

Blood Plasma Calorimetric Profiles of Women with Preeclampsia: Effect of Oxidative Stress

Preeclampsia is a pregnancy-related disease with poor placentation and presents itself through hypertension and proteinuria. The disease is also associated with the oxidative modification of proteins in maternal blood plasma. In this work, we combine differential scanning calorimetry (DSC), capillary electrophoresis, and atomic force microscopy (AFM) to evaluate the changes in the plasma denaturation profiles of patients with preeclampsia (PE) as compared with those of pregnant controls. Our results demonstrate that the last trimester of pregnancy substantially affects the main calorimetric characteristics of blood plasma from pregnant controls relative to nonpregnant women. These variations correlate well with the changes in protein levels determined by electrophoresis. DSC analysis revealed significant deviations in the plasma heat capacity profiles of preeclamptic patients from those of pregnant controls. These alterations are expressed mainly in a substantial reduction in albumin-assigned transitions and an upward shift in its denaturation temperature, lower calorimetric enthalpy changes, and a reduced ratio of heat capacity in the albumin/globulin-assigned thermal transitions, which are more pronounced in severe PE cases. The in vitro oxidation model shows that the alteration of PE thermograms is partly related to protein oxidation. AFM data detected numerous aggregate formations in the plasma of PE samples and fewer small ones in the pregnant controls, which are not found in healthy nonpregnant samples. These findings could serve as a basis for further investigations to reveal the possible relationship between albumin thermal stabilization, the increased inflammatory state and oxidative stress, and protein misfolding in preeclampsia.

Individual, Independent, and Joint Associations of Toxic Metals and Manganese on Hypertensive Disorders of Pregnancy: Results from the MIREC Canadian Pregnancy Cohort

BACKGROUND

Toxic metals, such as lead (Pb), cadmium (Cd), arsenic (As), and mercury (Hg), may be associated with a higher risk of gestational hypertension and preeclampsia, whereas manganese (Mn) is an essential metal that may be protective.

OBJECTIVES

We estimated the individual, independent, and joint associations of Pb, Cd, As, Hg, and Mn on the risk of developing gestational hypertension and preeclampsia in a cohort of Canadian women.

METHODS

Metal concentrations were analyzed in first and third trimester maternal blood (n = 1,560 ). We measured blood pressure after 20 wk gestation to diagnose gestational hypertension, whereas proteinuria and other complications defined preeclampsia. We estimated individual and independent (adjusted for coexposure) relative risks (RRs) for each doubling of metal concentrations and examined interactions between toxic metals and Mn. We used quantile g-computation to estimate the joint effect of trimester-specific exposures.

RESULTS

Each doubling of third trimester Pb (RR = 1.54 ; 95% CI: 1.06, 2.22) and first trimester blood As (RR = 1.25 ; 95% CI: 1.01, 1.58) was independently associated with a higher risk of developing preeclampsia. First trimester blood As (RR = 3.40 ; 95% CI: 1.40, 8.28) and Mn (RR = 0.63 ; 95% CI: 0.42, 0.94) concentrations were associated with a higher and lower risk, respectively, of developing gestational hypertension. Mn modified the association with As such that the deleterious association with As was stronger at lower concentrations of Mn. First trimester urinary dimethylarsinic acid concentrations were not associated with gestational hypertension (RR = 1.31 ; 95% CI: 0.60, 2.85) or preeclampsia (RR = 0.92 ; 95% CI: 0.68, 1.24). We did not observe overall joint effects for blood metals.

DISCUSSION

Our results confirm that even low blood Pb concentrations are a risk factor for preeclampsia. Women with higher blood As concentrations combined with lower Mn in early pregnancy were more likely to develop gestational hypertension. These pregnancy complications impact maternal and neonatal health. Understanding the contribution of toxic metals and Mn is of public health importance. https://doi.org/10.1289/EHP10825.

Alterations in Vessel Hemodynamics Across Uncomplicated Pregnancy

Pregnancy is marked by the onset of rapid hemodynamic alterations in order to accommodate the needs of the developing fetus. Arterial stiffness is an independent predictor of cardiovascular events and mortality, and its measurement in clinical practice has been recommended. It follows a U-shaped curve in uncomplicated pregnancy, decreasing to a nadir in mid-pregnancy and rising at term. Systemic vasodilation occurs due to elevated nitric oxide, prostacyclin, endothelium-derived hyperpolarizing factor, estrogen, progesterone, and relaxin. Vascular resistance decreases to a nadir in mid-pregnancy, while endothelial function is enhanced starting in the first trimester. Plasma volume increases by about 50%, and total red blood cell mass increases by up to 40%. Cardiac output increases by up to 45%, at first due primarily to elevated stroke volume, then mainly due to increased heart rate. Along with echocardiography, cardiac magnetic resonance imaging is safe for use in pregnancy. It may assess cardiac function more accurately than echocardiography, and may be indicated in specific clinical cases. Moreover, blood pressure decreases to a nadir in mid-pregnancy and rises to near preconception values postpartum. An appreciation of the vascular changes occurring in healthy pregnancy can aid in the prediction and diagnosis of pregnancy complications, such as preeclampsia and other hypertensive disorders of pregnancy, and inform treatment. In particular, noninvasive arterial stiffness/hemodynamics assessment provides unique clinical information beyond blood pressure and traditional maternal characteristics, and can signal a need for further testing, or be used in combination with other tests to predict or diagnose complications of pregnancy.

Gestational hemodilution as a putative risk factor for postpartum depression: A large-scale nationwide longitudinal cohort study

BACKGROUND

While anemia during pregnancy has been linked to increased postpartum depression (PPD) risk, longitudinal studies on the association between gestational hemodilution, represented by decreased hematocrit (Hct) during the transition from the 1st to 2nd trimester, and PPD risk, are scarce. The current study aimed to investigate this association in a nationwide cohort over the perinatal period.

METHODS

This retrospective cohort study included 104,715 women who gave birth between January 2008 and December 2015. The cohort was followed up for new-onset PPD during the year post birth and gestational hemodilution was assessed by the change in Hct levels (Δ: 2nd-1st trimester). The cohort was divided into three hemodilution groupings: maximal and minimal 10 % of mothers and intermediate 80 %. Multivariable regression analyses were performed to estimate the association between gestational hemodilution and PPD, adjusting for confounders.

RESULTS

Among the full cohort, 2.2 % (n = 2263) met the definition of new-onset PPD. Mothers with greater hemodilution had higher rates of PPD: 2.7 % (n = 269) in the maximal hemodilution group, 2.1 % (n = 1783) in the intermediate and 1.9 % (n = 211) in the minimal hemodilution group (p < 0.001). The maximal hemodilution group had higher rates of pre-gestational psychiatric disorders (p < 0.001) and higher adjusted risk for PPD [OR = 1.18, 95 % CI (1.04, 1.35)].

LIMITATIONS

Data on iron levels and supplementation were unavailable, thus it could not be adjusted for in the analysis.

CONCLUSIONS

Women in the top 10th percentile of gestational hemodilution may be at risk for PPD, justifying monitoring of gestational Hct as a biomarker for PPD.

Longitudinal maternal cardiac function in hypertensive disorders of pregnancy

BACKGROUND

Compared with gestational hypertension, preeclampsia has traditionally been considered the worse end of the spectrum of hypertensive disorders of pregnancy. It is associated with worse pregnancy outcomes and future cardiovascular morbidities. Both hypertensive disorders may be associated with cardiac maladaptation in pregnancy. However, previous studies were limited by small numbers and a paucity of longitudinal data and unaccounted for the contribution of maternal characteristics that can affect hemodynamics.

OBJECTIVE

This study aimed to assess, in an unselected population, the maternal cardiac adaptation in normotensive and hypertensive pregnancies after controlling for important maternal characteristics that affect maternal cardiac function and the interaction among these covariates.

STUDY DESIGN

This was a prospective, multicenter longitudinal study of maternal hemodynamics, assessed by a noninvasive bioreactance technology, measured at 11 0/7 to 13 6/7, 19 0/7 to 24 0/7, 30 0/7 to 34 0/7, and 35 0/7 to 37 0/7 weeks of gestation in 3 groups of women. Group 1 was composed of women with preeclampsia (n=45), group 2 was composed of women with gestational hypertension (n=61), and group 3 was composed of normotensive women (n=1643). A multilevel linear mixed-effects model was performed to compare the repeated measures of hemodynamic variables controlling for maternal age, height, weight, weight gain, race, previous obstetrical history, and birthweight.

RESULTS

After adjusting for confounders that significantly affect maternal hemodynamics, both group 1 and group 2, compared with group 3, had pathologic cardiac adaptation. Group 1, compared with group 3, demonstrated hyperdynamic circulation with significantly higher cardiac output driven by greater stroke volume in the first trimester of pregnancy. As the pregnancies progressed to after 20 0/7 weeks of gestation, this hyperdynamic state transitioned to hypodynamic state with low cardiac output and high peripheral vascular resistance. Group 2, compared with group 3, had no significant differences in cardiac output, stroke volume, and heart rate before 20 0/7 weeks of gestation but thereafter demonstrated a continuous decline in cardiac output and stroke volume, similar to group 1. Both groups 1 and 2, compared with group 3, had persistently elevated mean arterial pressure and uterine artery pulsatility index throughout pregnancy.

CONCLUSION

After adjusting for confounders that affect maternal hemodynamics in an unselected pregnant population, women with preeclampsia and gestational hypertension, compared with normotensive women, demonstrated similar cardiac maladaptation. This pathologic profile was evident after 20 0/7 weeks of gestation and at least 10 weeks before the clinical manifestation of the disease.

Beta-Blockers in Pregnancy: Clinical Update

PURPOSE OF REVIEW

The aim of this review was to determine the anticipated benefits and adverse effects of beta-blockers in pregnant women with hypertension. The other issue was to assess the possible adverse effects of beta-blockers for their babies and provide current consensus recommendations for appropriate selection and individualized antihypertensive treatment with beta-blockers in pregnancy-associated hypertension.

RECENT FINDINGS

Hypertensive disorders of pregnancy are a major cause of maternal and fetal morbidity, with consequences later in life. Certain beta-blockers are useful for ameliorating hypertension in pregnancy and may have a protective role in endothelial dysfunction. However, some aspects of beta-blocker use in pregnancy are contentious among providers. Evidence on their safety, although well documented, is variable, and recent research reveals areas of controversy. Besides intrauterine growth restriction, other neonatal and obstetric complications remain a concern and should be explored thoroughly. Attention is necessary when treating pregnancy-associated hypertensive disorders with beta-blockers. Specific beta-blockers are considered safe in pregnancy, although the associated effects in the fetus are not clearly known and evidence is lacking for many safety outcomes, other than intrauterine growth restriction. Nevertheless, beta-blockers with specific indications in pregnancy under individualized selection and monitoring may confer substantial improvements in pregnant women with hypertension.

Association of Fatty Acid Desaturase 1 rs174547 Polymorphism with the Composition of Long-Chain Polyunsaturated Fatty Acids in Serum Glycerophospholipids during Pregnancy

The increase in fetal requirements of long-chain polyunsaturated fatty acids (LCPUFAs) during pregnancy alters maternal fatty acid metabolism, and therefore, fatty acid desaturase (FADS) gene polymorphisms may change blood fatty acid composition or concentration differently during pregnancy. We investigated the relationship between a FADS1 single-nucleotide polymorphism (SNP) and maternal serum LCPUFA levels in Japanese pregnant women during the first and third trimesters and at delivery. Two hundred and fifty-three pregnant women were included, and fatty acid compositions of glycerophospholipids in serum (weight %) and the FADS1 SNP rs174547 (T/C) were analyzed. LCPUFAs, including arachidonic acid (ARA) and docosahexaenoic acid (DHA), significantly decreased from the first to the third trimester of pregnancy. Furthermore, DHA significantly decreased from the third trimester of pregnancy to delivery. At all gestational stages, linoleic acid (LA) and α-linolenic acid were significantly higher with the number of minor FADS1 SNP alleles, whereas γ-linolenic acid and ARA and the ARA/LA ratio were significantly lower. DHA was significantly lower with the number of minor FADS1 SNP alleles only in the third trimester and at delivery, suggesting that genotype effects become more obvious as pregnancy progresses.

Hypertensive disorders of pregnancy and long-term cardiovascular health: FIGO Best Practice Advice

Hypertensive disorders of pregnancy (HDP) are the most common causes of maternal and perinatal morbidity and mortality. They are responsible for 16% of maternal deaths in high-income countries and approximately 25% in low- and middle-income countries. The impact of HDP can be lifelong as they are a recognized risk factor for future cardiovascular disease. During pregnancy, the cardiovascular system undergoes significant adaptive changes that ensure adequate uteroplacental blood flow and exchange of oxygen and nutrients to nurture and accommodate the developing fetus. Failure to achieve normal cardiovascular adaptation is associated with the development of HDP. Hemodynamic alterations in women with a history of HDP can persist for years and predispose to long-term cardiovascular morbidity and mortality. Therefore, pregnancy and the postpartum period are an opportunity to identify women with underlying, often unrecognized, cardiovascular risk factors. It is important to develop strategies with lifestyle and therapeutic interventions to reduce the risk of future cardiovascular disease in those who have a history of HDP.

Prepregnancy Body Mass Index and Lipoprotein Fractions are Associated with Changes in Women's Serum Metabolome from Late Pregnancy to the First Months of Postpartum

BACKGROUND

Pregnancy and postpartum are periods of intense changes in women's metabolism. The knowledge of the metabolites and maternal factors underlying these changes is limited.

OBJECTIVES

We aimed to investigate the maternal factors that could influence serum metabolome changes from late pregnancy to the first months of postpartum.

METHODS

Sixty-eight healthy women from a Brazilian prospective cohort were included. Maternal blood and general characteristics were collected during pregnancy (28-35 wk) and postpartum (27-45 d). A targeted metabolomics approach was applied to quantify 132 serum metabolites, including amino acids, biogenic amines, acylcarnitines, lysophosphatidylcholines (LPC), diacyl phosphatidylcholines (PC), alkyl:acyl phosphatidylcholines (PC-O), sphingomyelins with (SM) and without hydroxylation [SM(OH)], and hexoses. Metabolome changes from pregnancy to postpartum were measured as log₂ fold change (log₂FC), and simple linear regressions were employed to evaluate associations between maternal variables and metabolite log₂FC. Multiple comparison-adjusted P values of < 0.05 were considered significant.

RESULTS

Of 132 metabolites quantified in serum, 90 changed from pregnancy to postpartum. Most metabolites belonging to PC and PC-O classes decreased, whereas most LPC, acylcarnitines, biogenic amines, and a few amino acids increased in postpartum. Maternal prepregnancy body mass index (ppBMI) showed positive associations with leucine and proline. A clear opposite change pattern was observed for most metabolites across ppBMI categories. Few phosphatidylcholines were decreased in women with normal ppBMI, while an increase was observed in women with obesity. Similarly, women with high postpartum levels of total cholesterol, LDL cholesterol, and non-HDL cholesterol showed increased sphingomyelins, whereas a decrease was observed for women with lower levels of those lipoproteins.

CONCLUSIONS

The results revealed several maternal serum metabolomic changes from pregnancy to postpartum, and the maternal ppBMI and plasma lipoproteins were associated with these changes. We highlight the importance of the nutritional care of women prepregnancy to improve their metabolic risk profile.

Urinary paracetamol (4-acetaminophenol) and its isomer 2-acetaminophenol of Chinese pregnant women: Exposure characteristics and association with oxidative stress biomarkers

N-Acetyl-4-aminophenol (NA4AP, paracetamol/acetaminophen), a widely used pharmaceutical, is ubiquitous in urine samples of general population, raising concern about human health risks; oxidative stress is considered to be a mechanism for its toxicities. N-Acetyl-2-aminophenol (NA2AP) is an isomer of NA4AP; until now, few studies characterized exposure characteristics of NA4AP and NA2AP in pregnant women. In this work, NA4AP and NA2AP concentrations in urine samples (n = 2124) collected at three different trimesters were measured to examine their internal body burden among Chinese pregnant women (n = 708) and their associations with three oxidative stress biomarkers (OSBs, 8-OHG, 8-OHdG, and HNE-MA). NA4AP was detected in 100% of the urine samples (median concentration: 7.96 ng/mL); NA2AP was detected in 94.9% of them (median: 3.05 ng/mL). The intraclass correlation coefficients of their concentrations across three trimesters were poor (<0.4); correlations of NA4AP and NA2AP were weak (r: 0.15-0.23). Pregnant women who had higher household income or urine samples provided in summer (vs. winter) had higher concentrations of NA4AP. Pregnant women who had a college degree or above (vs. less than a high school education) had higher concentrations of NA2AP but urine samples provided in summer (vs. winter) had lower concentrations of NA2AP. The 95th percentile estimated daily intake of NA4AP (2,331 ng/kg-bw/d) based on averaged concentrations of the three trimesters was 40 times lower than the cRfD for NA4AP (2.33 vs. 93 μg/kg-bw/d). Urinary concentrations of NA4AP and NA2AP were associated with higher levels of the selected OSBs. For example, an interquartile range increase in NA4AP was associated with a 26.5% (95% CI: 23.6-29.6%) increase in 8-OHG, a 27.5% (95% CI: 23.8-31.3%) increase in 8-OHdG, and a 33.4% (95% CI: 24.7-42.7%) increase in HNE-MA (p < 0.05). This is the first study to measure their concentrations repeatedly over three trimesters, examine their exposure characteristics, and reveal their associations with the selected OSBs in pregnant women. Further studies are needed to identify non-intentional exposure sources of NA4AP, NA2AP, and another isomer of them (i.e., N-acetyl-3-aminophenol), as well as more health risks related to their exposure.

Do maternal albumin levels affect post-operative complications after cesarean delivery?

BACKGROUND

This study explored the correlation between maternal serum albumin levels prior to elective cesarean delivery (CD) and postoperative complications.

METHODS

This retrospective cohort study included women admitted for elective CD at term to our tertiary referral center, during the years 2016-2018. Blood samples were collected during the preoperative admission. Information collected included maternal demographics, pregnancy and postoperative complications. Data between patients with preoperative serum albumin levels < 3.3 g/dL or ≥ 3.3 g/dL were compared.

RESULTS

Among 796 women admitted for an elective CD, 537 met the inclusion criteria. There were 250 (46.6%) women in the low albumin level group (< 3.3 g/dL) and 287 (53.4%) with serum albumin level ≥ 3.3 g/dL. Patients with serum albumin ≥ 3.3 g/dL had increased rates of surgical site infection (SSI) (5.6% vs. 1.6% respectively; p = 0.02), need for antibiotics during the post-partum period (10.8% vs 3.2%, respectively; p = 0.001), surgical intervention (2.1% vs. 0%, respectively; p = 0.03) and higher rate of rehospitalization (5.2% vs. 0.4%, respectively; p = 0.001). Multivariant analysis showed that albumin level ≥ 3.3 g/dL was independently associated with composite postoperative adverse maternal outcome.

CONCLUSIONS

High serum albumin levels among women undergoing CD, might be associated with abnormal postoperative outcomes. Larger prospective studies, with a heterogenous population are needed to validate these observations.

The incidence, complications, and treatment of iron deficiency in pregnancy

Iron deficiency and/or iron deficiency anemia (IDA) complicate nearly 50% of pregnancies globally, negatively impacting both maternal and fetal outcomes. Iron deficiency can cause a range of symptoms that range from aggravating to debilitating including fatigue, poor quality of life, pagophagia, and restless leg syndrome. Iron deficiency and IDA are also associated with maternal complications including preterm labor, increased rates of cesarean delivery, postpartum hemorrhage, and maternal death. Fetal complications include increased rates of low birth weight and small for gestational age newborns. Prenatal maternal anemia has also been associated with autism spectrum disorders in the neonate, although causation is not established. Deficiency in the newborn is associated with compromised memory, processing, and bonding, with some of these deficits persisting into adulthood. Despite the prevalence and consequences associated with iron deficiency in pregnancy, data show that it is routinely undertreated. Due to the physiologic changes of pregnancy, all pregnant individuals should receive oral iron supplementation. However, the bioavailability of oral iron is poor and it is often ineffective at preventing and treating iron deficiency. Likewise, it frequently causes gastrointestinal symptoms that can worsen the quality of life in pregnancy. Intravenous iron formulations administered in a single or multiple dose series are now available. There is increasing data suggesting that newer intravenous formulations are safe and effective in the second and third trimesters and should be strongly considered in pregnant individuals without optimal response to oral iron repletion.

The Significance of COVID-19 Diseases in Lipid Metabolism Pregnancy Women and Newborns

Coronavirus disease (COVID-19) is an infectious disease caused by SARS-CoV-2. Elderly people, people with immunodeficiency, autoimmune and malignant diseases, as well as people with chronic diseases have a higher risk of developing more severe forms of the disease. Pregnant women and children can becomesick, although more often they are only the carriers of the virus. Recent studies have indicated that infants can also be infected by SARS-CoV-2 and develop a severe form of the disease with a fatal outcome. Acute Respiratory Distress Syndrome (ARDS) ina pregnant woman can affect the supply of oxygen to the fetus and initiate the mechanism of metabolic disorders of the fetus and newborn caused by asphyxia. The initial metabolic response of the newborn to the lack of oxygen in the tissues is the activation of anaerobic glycolysis in the tissues and an increase in the concentration of lactate and ketones. Lipid peroxidation, especially in nerve cells, is catalyzed by iron released from hemoglobin, transferrin and ferritin, whose release is induced by tissue acidosis and free oxygen radicals. Ferroptosis-inducing factors can directly or indirectly affect glutathione peroxidase through various pathways, resulting in a decrease in the antioxidant capacity and accumulation of lipid reactive oxygen species (ROS) in the cells, ultimately leading to oxidative cell stress, and finally, death. Conclusion: damage to the mitochondria as a result of lipid peroxidation caused by the COVID-19 disease can cause the death of a newborn and pregnant women as well as short time and long-time sequelae.

Plasma metabolic disturbances during pregnancy and postpartum in women with depression

Examining plasma metabolic profiling during pregnancy and postpartum could help clinicians understand the risk factors for postpartum depression (PPD) development. This analysis targeted paired plasma metabolites in mid-late gestational and 1 month postpartum periods in women with (n = 209) or without (n = 222) PPD. Gas chromatogram-mass spectrometry was used to analyze plasma metabolites at these two time points. Among the 170 objected plasma metabolites, principal component analysis distinguished pregnancy and postpartum metabolites but failed to discriminate women with and without PPD. Compared to women without PPD, those with PPD exhibited 37 metabolites with disparate changes during pregnancy and the 1-month postpartum period and an enriched citrate cycle. Machine learning and multivariate statistical analysis identified two or three compounds that could be potential biomarkers for PPD prediction during pregnancy. Our findings suggest metabolic disturbances in women with depression and may help to elucidate metabolic processes associated with PPD development.

Modeling renal autoregulation in a hemodynamic, first-trimester gestational model

The maternal cardiovascular system, led by renal volume regulatory responses, changes during pregnancy to ensure an adequate circulation for fetal development and growth. Circulatory maladjustment predisposes to hypertensive complications during pregnancy. Mathematical models can be used to gain insight in the gestational cardiovascular physiology. In this study, we developed an accurate, robust, and transparent model for renal autoregulation implemented in an existing circulatory gestational model. This renal autoregulation model aims to maintain steady glomerular pressure by the myogenic response, and glomerular filtration rate by tubuloglomerular feedback, both by inducing a change in the radius, and thus resistance, of the afferent arteriole. The modeled response of renal blood flow and the afferent arteriole following blood pressure increase were compared to published observations in rats. With solely the myogenic response, our model had a maximum deviation of 7% in change in renal blood flow and 7% in renal vascular resistance. When both the myogenic response and tubuloglomerular feedback were concurrently activated, the maximum deviation was 7% in change in renal blood flow and 5% in renal vascular resistance. These results show that our model is able to represent renal autoregulatory behavior comparable to empirical data. Further studies should focus on extending the model with other regulatory mechanisms to understand the hemodynamic changes in healthy and complicated pregnancy.

Beneficios del uso del hierro parenteral como alternativa eficaz en el manejo de la anemia gestacional en Colombia

Introducción. La Organización Mundial de la Salud (OMS) estima que más del 40% de las mujeres embarazadas a nivel mundial tienen anemia, y la mitad de estas padecen deficiencia de hierro. La prevalencia en América Latina es del 40% y en Colombia del 44.7%. Fisiológicamente en el embarazo se produce una mal llamada “anemia dilucional”, existen condiciones en la embarazada que la predisponen a tener una anemia patológica. Esta última es causada principalmente por un déficit de hierro, de allí la importancia de diagnosticar a tiempo esta entidad e iniciar el manejo. La administración de hierro es la base del tratamiento de la anemia por deficiencia de hierro. Puede ser administrado por vía oral, la cual es la preferida en la mayoría de las pacientes; sin embargo, cuando este no es posible administrarlo, es esencial recurrir al hierro parenteral. No obstante, el hierro parenteral es poco usado como primera línea en el manejo de la anemia gestacional. El presente artículo tiene como objetivo realizar una revisión que permita identificar la terapia con hierro parenteral como una alternativa eficaz de manejo para la anemia gestacional, teniendo en cuenta las características farmacológicas, la administración y el uso entre las diferentes moléculas disponibles en Colombia. Metodología. Corresponde a un estudio de revisión de literatura en bases de datos y bibliotecas electrónicas, los criterios que se tuvieron en cuenta fueron textos publicados entre 1996 y 2020, en español e inglés. Se obtuvo un resultado de 95 artículos, de los cuales se seleccionaron 49. Las palabras clave para su búsqueda fueron fisiología, hierro parenteral, anemia gestacional, déficit de hierro, complicaciones del embarazo, compuestos de hierro, farmacocinética, diagnóstico y tratamiento. División de temas tratados. Fisiología; ayudas diagnósticas; características farmacológicas del hierro parenteral; ventajas, indicaciones y contraindicaciones del hierro parenteral; efectos secundarios y forma de aplicación. Conclusiones. El hierro parenteral es un tratamiento seguro y eficaz para manejar la anemia en el embarazo, se debe tener en cuenta las indicaciones y la farmacología de las moléculas para elegir la más adecuada. Además, repone más rápidamente las reservas de hierro y los niveles de hemoglobina.

Maternal body weight and estimated circulating blood volume: a non-linear approach

Postpartum haemorrhage continues to be a leading cause of morbidity and mortality in the obstetric population worldwide, especially in patients at extremes of body weight. Quantification of blood loss has been considered extensively in the literature. However, these volumes must be contextualised to appreciate the consequences of blood loss for individual parturients. Knowledge of a patient's peripartum circulating blood volume is essential to allow accurate interpretation of the significance of haemorrhage and appropriate resuscitation. Greater body weight in obesity can lead to overestimation of blood volume, resulting in inappropriately high thresholds for blood product transfusion and delays in treatment. The most recent Mothers and Babies: Reducing Risk through Audits and Confidential Enquiries across the UK (MBRRACE-UK) surveillance report demonstrated the risk to this population, with more than half of all maternal mortality recorded in parturients who were either overweight or obese. Current linear calculations used to estimate circulating blood volumes based on patients' weights could be contributing to this phenomenon, as blood volume increases at a disproportional rate to body composition. In this review, we summarise the relevant physiology and explore the existing literature on the estimation of circulating blood volume, both during pregnancy and in obesity. Building on key works and principal findings, we present a practical, nonlinear approach to the adjustment of estimated blood volume with increasing body mass. This clinical tool aims to reduce the clinical bias influencing the management of obstetric haemorrhage in a population already at increased risk of morbidity and mortality. Discussion of the limitations of this approach and the call for further research within this field completes this review.

Prenatal Exposure to PM2.5 and Its Specific Components and Risk of Hypertensive Disorders in Pregnancy: A Nationwide Cohort Study in China

Hypertensive disorders in pregnancy (HDP) are a leading cause of maternal mortality and adverse birth outcomes. Fine particulate matter (PM_2.5) has been linked to HDP risk; however, limited studies have explored the relationships between specific chemical constituents of PM_2.5 and HDP risk. Based on maternal data from the China Labor and Delivery Survey (CLDS), this study included a total of 67,659 participants from 95 participant hospitals in 25 provinces of China between March 1, 2015, and December 31, 2016. Maternal exposure to total PM_2.5 mass and six main components during pregestation and pregnancy were estimated using the Combined Geoscience-Statistical Method. Multilevel logistic regression models were applied to quantify the associations, controlling for sociodemographic characteristics. We found that an interquartile range (IQR) increase in PM_2.5 exposure during the second trimester was associated with a 14% increase in HDP risk (95% CI: 2%, 29%). We observed that black carbon (BC) and SO₄^2- had larger or comparable estimates of the effect than total PM_2.5 mass. The association estimates were greater in the gestational hypertension group than in the group of pre-eclampsia and eclampsia. Our findings suggest that PM_2.5 exposure and specific chemical components (particularly BC and SO₄^2-) were associated with an increased HDP risk in China.

Pentachlorophenol exposure in early pregnancy and gestational diabetes mellitus: A nested case-control study

Pentachlorophenol (PCP) is an endocrine-disrupting chemical that is ubiquitously found in the environment. Few studies have reported PCP exposure in pregnant women and its association with gestational diabetes mellitus (GDM). This nested case-control study aimed to determine the concentration of urinary PCP in early pregnancy and explore the association between PCP exposure and GDM risk. This study included 293 GDM cases and 586 non-GDM controls matched by fetal sex and maternal age from a birth cohort in Wuhan, China. PCP concentrations in spot urine samples collected between 8 and 16 weeks of gestation were measured by ultra-performance liquid chromatography-tandem mass spectrometry. Conditional logistic regression was used to assess the association between PCP exposure and the odds ratio of GDM. The median concentrations of specific gravity-adjusted PCP in controls and cases were 0.70 and 0.80 ng/mL, respectively, with no significant differences (P > 0.05). The multivariate-adjusted odds ratios (ORs) (95% confidence intervals) for GDM across quartiles of urinary PCP were 1 (reference), 1.63 (1.06-2.50), 1.70 (1.11-2.61), and 1.35 (0.87-2.08), respectively, showing a potential "inverted-U" shaped association. In addition, PCP levels and maternal age or fetal sex had significant interactions with GDM risk (both P for interaction < 0.05). Among older women and those carrying female fetuses, the ORs of GDM risk were higher. This study suggests that pregnant women in central China are widely exposed to PCP, and this is the first time to report that PCP exposure may increase the risk of GDM (with potential effect modifications by maternal age and fetal sex). The association observed is in agreement with PCP's "inverted-U" anti-estrogenic effect in vivo; thus, such an effect in humans at environmentally relevant doses should be studied further.

Maternal Low Volume Circulation Relates to Normotensive and Preeclamptic Fetal Growth Restriction

This narrative review summarizes current evidence on the association between maternal low volume circulation and poor fetal growth. Though much work has been devoted to the study of cardiac output and peripheral vascular resistance, a low intravascular volume may explain why high vascular resistance causes hypertension in women with preeclampsia (PE) that is associated with fetal growth restriction (FGR) and, at the same time, presents with normotension in FGR itself. Normotensive women with small for gestational age babies show normal gestational blood volume expansion superimposed upon a constitutionally low intravascular volume. Early onset preeclampsia (EPE; occurring before 32 weeks) is commonly associated with FGR, and poor plasma volume expandability may already be present before conception, thus preceding gestational volume expansion. Experimentally induced low plasma volume in rodents predisposes to poor fetal growth and interventions that enhance plasma volume expansion in FGR have shown beneficial effects on intrauterine fetal condition, prolongation of gestation and birth weight. This review makes the case for elevating the maternal intravascular volume with physical exercise with or without Nitric Oxide Donors in FGR and EPE, and evaluating its role as a potential target for prevention and/or management of these conditions.

A Critical Analysis of the Automated Hematology Assessment in Pregnant Women at Low and at High Altitude: Association between Red Blood Cells, Platelet Parameters, and Iron Status

The objectives of the study were to determine differences in the parameters of red blood cells (RBC), white blood cells (WBC), and platelets at low altitude (LA) and at high altitude (HA) and with the gestation being advanced, and to determine correlations between parameters of RBC and platelets. We also studied the association of RBC and platelets with markers of iron status. In addition, markers of iron status and inflammation were measured and compared at each trimester of gestation in pregnant women at LA and HA. A cross-sectional comparative study was conducted at Lima (150 m above sea level) and Cusco at 3400 m above sea level from May to December 2019. Hematological parameters in pregnant women (233 at LA and 211 at HA) were analyzed using an automated hematology analyzer. Serum ferritin levels, soluble transferrin receptor (sTfR), hepcidin, erythropoietin, testosterone, estradiol, and interleukin-6 (IL6) levels were measured by ELISA. One-way ANOVA supplemented with post hoc test, chi-square test, and Pearson correlation test statistical analyses were performed. p < 0.05 was considered significant. Pregnant woman at HA compared to LA had significantly lower WBC (p < 0.01), associated with higher parameters of the RBC, except for the mean corpuscular volume (MCV) that was no different (p > 0.05). Platelets and mean platelet volume (MPV) were higher (p < 0.01), and platelet distribution width (PDW) was lower at HA than at LA (p < 0.01). A higher value of serum ferritin (p < 0.01), testosterone (p < 0.05), and hepcidin (p < 0.01) was observed at HA, while the concentration of sTfR was lower at HA than at LA (p < 0.01). At LA, neutrophils increased in the third trimester (p < 0.05). RBC parameters decreased with the progress of the gestation, except RDW-CV, which increased. The platelet count decreased and the MPV and PDW were significantly higher in the third trimester. Serum ferritin, hepcidin, and serum testosterone decreased, while sTfR and serum estradiol increased during gestation. At HA, the WBC and red blood cell distribution width- coefficient of variation (RDW-CV), PCT, and serum IL-6 did not change with gestational trimesters. RBC, hemoglobin (Hb), hematocrit (Hct), mean corpuscular hemoglobin concentration (MCHC), and platelet count were lower as gestation advanced. MCV, MPV, and PDW increased in the third trimester. Serum ferritin, testosterone, and hepcidin were lower in the third trimester. Serum estradiol, erythropoietin, and sTfR increased as gestation progressed. Direct or inverse correlations were observed between RBC and platelet parameters and LA and HA. A better number of significant correlations were observed at HA. Hb, Hct, and RDW-CV showed a significant correlation with serum ferritin at LA and HA. Of these parameters, RDW-CV and PDW showed an inversely significant association with ferritin (p < 0.05). In conclusion, a different pattern was observed in hematological markers as well as in iron status markers between pregnant women at LA and HA. In pregnant women a significant correlation between several RBC parameters with platelet marker parameters was also observed. Data suggest that pregnant women at HA have adequate iron status during pregnancy as reflected by higher serum ferritin levels, lower sTfR levels, and higher hepcidin values than pregnant women at LA.

Changes in Serum Levels of Ketone Bodies and Human Chorionic Gonadotropin during Pregnancy in Relation to the Neonatal Body Shape: A Retrospective Analysis

Among the physiological changes occurring during pregnancy, the benefits of morning sickness, which is likely mediated by human chorionic gonadotropin (HCG) and induces serum ketone production, are unclear. We investigated the relationship between serum levels of ketone bodies and HCG in the first, second, and third trimesters and neonatal body shape (i.e., birth weight, length, head circumference, and chest circumference) in 245 pregnant women. Serum levels of 3-hydroxybutyric acid peaked in late-stage compared with early stage pregnancy (27.8 [5.0−821] vs. 42.2 [5.0−1420] μmol/L, median [range], p < 0.001). However, serum levels of ketone bodies and HCG did not correlate with neonatal body shape. When weight loss during pregnancy was used as an index of morning sickness, a higher pre-pregnancy body mass index was associated with greater weight loss. This study is the first to show that serum ketone body levels are maximal in the third trimester of pregnancy. As the elevation of serum ketone bodies in the third trimester is a physiological change, high serum levels of ketone bodies may be beneficial for mothers and children. One of the possible biological benefits of morning sickness is the prevention of diseases that have an increased incidence due to weight gain during pregnancy.