Clinical biochemistry of pregnancy

Cardiovascular complications during pregnancy: Advancing cardio-obstetrics

As the incidence of cardiovascular diseases (CVDs) continues to rise among women of childbearing age, the pregnant population with pre-existing heart conditions presents a complex and heterogeneous profile. These women face varying degrees of risk concerning maternal cardiovascular, obstetric, and fetal complications. Effectively managing adverse cardiovascular events during pregnancy presents substantial clinical challenges. The uncertainties surrounding diagnostic and therapeutic approaches create a dynamic landscape with potential implications for maternal and fetal health. Cardio-obstetrics has become increasingly recognized as a vital multidisciplinary field necessitating a collaborative approach to managing cardiovascular conditions during pregnancy. In this review, we aim to provide a thorough and up-to-date examination of the existing evidence, offering a comprehensive overview of strategies and considerations in the management of cardiovascular complications during pregnancy. Special emphasis is placed on the safety assessment of diagnostic procedures and the exploration of treatment options designed to prioritize the well-being of the mother and fetus. We also explore the significance of a multidisciplinary cardio-obstetrics team in providing comprehensive care for women of childbearing age with or at risk for CVD.

Women Skin Microbiota Modifications during Pregnancy

Several studies have shown fluctuations in the maternal microbiota at various body sites (gut, oral cavity, and vagina). The skin microbiota plays an important role in our health, but studies on the changes during pregnancy are limited. Quantitative and qualitative variations in the skin microbiota in pregnant woman could indeed play important roles in modifying the immune and inflammatory responses of the host. These alterations could induce inflammatory disorders affecting the individual's dermal properties, and could potentially predict infant skin disorder in the unborn. The present study aimed to characterize skin microbiota modifications during pregnancy. For this purpose, skin samples were collected from 52 pregnant women in the first, second, and third trimester of non-complicated pregnancies and from 17 age- and sex-matched healthy controls. The skin microbiota composition was assessed by next generation sequencing (NGS) of the V3-V4 region of the bacterial rRNA 16S. Our results indicate that from the first to the third trimester of pregnancy, changes occur in the composition of the skin microbiota, microbial interactions, and various metabolic pathways. These changes could play a role in creating more advantageous conditions for fetal growth.

Association between gut microbiota, microbial network, and immunity in pregnancy with a focus on specific bacterial clusters

Background

The community characteristics of the gut microbiota are not well defined and are not as widely studied as the functions of individual bacteria. This study aims to investigate the community composition of intestinal flora in women of childbearing age by conducting cluster analysis of gut microbiota and analyzing the relationship between different clusters and immune status.

Methods

A total of 45 women of childbearing age were recruited in the study, including 15 non-pregnant women and 30 women in late pregnancy, and stool samples were collected twice during the third trimester, specifically at 32 weeks and at full term. The gut microbiota data was analyzed using 16S rRNA amplicon sequencing. Partitioning Around Medoids algorithm was employed to assess microbial clustering patterns. Microbial network for each cluster was performed and plasm cytokines were measured to analyze the relationship between specific genera and immune state in clusters.

Results

There were three distinct clusters of intestinal community composition in women of childbearing age. Cluster 1 (PAM_1) was characterized by a high abundance of Bacteroides, while cluster 2 (PAM_2) showed higher levels of Bifidobacterium and Blautia, along with a significantly increased Firmicutes to Bacteroidota ratio. Cluster 3 (PAM_3) displayed a high abundance of Escherichia-shigella. PAM_1 was the most dominant cluster in non-pregnant women, and this dominant cluster was also one of the main in late pregnancy. At full term, the majority of subjects retained the same cluster as at 32 weeks, while a few experienced a shift. The microbial correlation networks differed across the three clusters, with PAM_1 exhibiting higher modularity and fewer connections. Analysis of the correlation between genera and plasma cytokines showed significant differences in their associations with cytokines between pregnancy and nonpregnancy within the same cluster, and the same genera had different effects in different clusters.

Conclusion

Women of childbearing age exhibit three distribution patterns of gut microbiota, and the intestinal clusters reshaped during late pregnancy in a small population. Different clusters may have diverse immunomodulatory effects in different physiological states. When studying the gut microbiome during pregnancy, it is crucial to consider the cluster differences within healthy women.

Fatty acids, inflammation and angiogenesis in women with gestational diabetes mellitus

Gestational diabetes mellitus (GDM) is a metabolic disorder in pregnancy whose prevalence is on the rise. Reports suggest a likely association between inflammation and maternal GDM. A balance between pro and anti-inflammatory cytokines is necessary for the regulation of maternal inflammation system throughout pregnancy. Along with various inflammatory markers, fatty acids also act as pro-inflammatory molecules. However, studies reporting the role of inflammatory markers in GDM are contradictory, suggesting the need of more studies to better understand the role of inflammation in pregnancies complicated by GDM. Inflammatory response can be regulated by angiopoietins suggesting a link between inflammation and angiogenesis. Placental angiogenesis is a normal physiological process which is tightly regulated during pregnancy. Various pro and anti-angiogenic factors influence the regulation of the feto-placental vascular development. Studies evaluating the levels of angiogenic markers in women with GDM are limited and the findings are inconsistent. This review summarizes the available literature on fatty acids, inflammatory markers and angiogenesis in women with GDM. We also discuss the possible link between them and their influence on placental development in GDM.

IMI-The Dynamic Choroid: New Insights, Challenges, and Potential Significance for Human Myopia

The choroid is the richly vascular layer of the eye located between the sclera and Bruch's membrane. Early studies in animals, as well as more recent studies in humans, have demonstrated that the choroid is a dynamic, multifunctional structure, with its thickness directly and indirectly subject to modulation by a variety of physiologic and visual stimuli. In this review, the anatomy and function of the choroid are summarized and links between the choroid, eye growth regulation, and myopia, as demonstrated in animal models, discussed. Methods for quantifying choroidal thickness in the human eye and associated challenges are described, the literature examining choroidal changes in response to various visual stimuli and refractive error-related differences are summarized, and the potential implications of the latter for myopia are considered. This review also allowed for the reexamination of the hypothesis that short-term changes in choroidal thickness induced by pharmacologic, optical, or environmental stimuli are predictive of future long-term changes in axial elongation, and the speculation that short-term choroidal thickening can be used as a biomarker of treatment efficacy for myopia control therapies, with the general conclusion that current evidence is not sufficient.

Pharmacokinetics of antibodies during pregnancy: General pharmacokinetics and pregnancy related physiological changes (Part 1)

Pharmacokinetics (PK) studies are important to determine a safe and effective dose of both small and large molecule drugs. Intrinsic factors such as pregnancy can substantially alter the PK of a drug. Several PK studies have been published for small molecules administered during pregnancy, but such investigations are scarce for macromolecules including monoclonal and polyclonal antibodies. In this part 1 of 2 reviews, we first provide a general description of macromolecule drugs, the PK differences with small molecules, and current knowledge on their absorption, distribution, metabolism and elimination in non-pregnant subjects. We then review in detail the physiological changes during pregnancy. While some of the physiologic adaptions of pregnancy, for example increased plasma volume and cardiac output, are expected to impact PK of antibody therapeutics, the effects of others, such as increased GFR and altered immune responses are not fully understood. We conclude that further investigations are needed to fully elucidate how pregnancy can impact PK properties of macromolecules.

Patterns of Medication Use and Their Determinants in Pregnancy among Women Admitted to the Obstetrics Wards of a Tertiary Care Hospital: A Cross-Sectional Study: Patterns of Medication Use and Their Determinants in Pregnancy

Background

To assess the patterns and factors affecting medication use during antenatal and perinatal periods and to examine maternal and fetal outcomes among pregnant women admitted to a tertiary care hospital in a developing country.

Methods

A cross-sectional study was conducted in the obstetrics wards from 2017 to 2019. Data on patient demographics, co-existent medical conditions, medications, and patient outcomes were collected. Descriptive statistics were used to analyze baseline data, chi-square test was used for categorical variables, and multivariate logistic regression was used for factors influencing drug prescription.

Results

Out of 442 pregnant women, 56% were primigravida with a mean age of 24.7 ± 3.9 years. Approximately 32% experienced at least one disease condition during pregnancy; hypothyroidism (9.7%) was the commonest. The mean number of medications was 2.7 and 38.9% received drugs for a disease condition. Antimicrobials (24.5%) were the commonest drug class. Maternal age of over 25 [(OR (CI): 1.508 (1.191–2.716) ( p = .005)] and maternal illness [OR (CI) 2.934 (1.8–4.7) ( p = .00)] were identified as factors affecting drug prescription. Approximately 39.8% of deliveries were cesarean. Of the newborns, 12.6% had low birth weight, 9.2% were admitted to the newborn intensive care unit, and 14.9% were premature.

Conclusions

Most patients were primigravida and under 25 years. Antimicrobials were the most prescribed drug class. Maternal age over 25 years and maternal illness were identified as the factors affecting medication use. The prevalence of cesareans and prematurity was similar to previous studies.

Allostatic Load and Adverse Pregnancy Outcomes

OBJECTIVE

To assess the association between allostatic load, as an estimate of chronic stress, and adverse pregnancy outcomes.

METHODS

This was a secondary analysis of nuMoM2b (Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-Be), a prospective observational cohort study. Our primary exposure was dichotomous high allostatic load in the first trimester, defined as 4 or more of 12 biomarkers in the "worst" quartile. The primary outcome was a composite adverse pregnancy outcome: hypertensive disorders of pregnancy (HDP), preterm birth, small for gestational age (SGA), and stillbirth. Secondary outcomes included components of the composite. Multivariable logistic regression was used to test the association between high allostatic load and adverse pregnancy outcomes, adjusted for potential confounders. Mediation and moderation analyses were conducted to assess the role of allostatic load along the causal pathway between racial disparities and adverse pregnancy outcomes.

RESULTS

Among 4,266 individuals, 34.7% had a high allostatic load. Composite adverse pregnancy outcome occurred in 1,171 (27.5%): 14.0% HDP, 8.6% preterm birth (48.0% spontaneous and 52.2% indicated), 11.0% SGA, and 0.3% stillbirth. After adjustment for maternal age, gravidity, smoking, bleeding in the first trimester, and health insurance, high allostatic load was significantly associated with a composite adverse pregnancy outcome (adjusted odds ratio [aOR] 1.5, 95% CI 1.3, 1.7) and HDP (aOR 2.5, 95% CI 2.0-2.9), but not preterm birth or SGA. High allostatic load partially mediated the association between self-reported race and adverse pregnancy outcomes. The association between allostatic load and HDP differed by self-reported race, but not for a composite adverse pregnancy outcome, preterm birth, or SGA.

CONCLUSION

High allostatic load in the first trimester is associated with adverse pregnancy outcomes, particularly HDP. Allostatic load was a partial mediator between race and adverse pregnancy outcomes. The association between allostatic load and HDP differed by self-reported race.

Pr-AKI: Acute Kidney Injury in Pregnancy – Etiology, Diagnostic Workup, Management

Despite significant improvements in inpatient and outpatient management, pregnancy-related acute kidney injury (Pr-AKI) remains an important risk factor for early and late maternal and fetal morbidity and mortality. There is a discrepancy between the incidence of Pr-AKI in developing and in developed countries, with the former experiencing a decrease and the latter an increase in Pr-AKI in recent decades. Whereas septic and hemorrhagic complications predominated in the past, nowadays hypertensive disorders and thrombotic microangiopathy are the leading causes of Pr-AKI. Modern lifestyles and the availability and widespread use of in-vitro fertilization techniques in industrialized countries have allowed more women of advanced age to become pregnant. This has led to a rise in the percentage of high-risk pregnancies due to the disorders and comorbidities inherent to or accompanying aging, such as diabetes, arterial hypertension and preexisting chronic kidney disease. Last but not least, the heterogeneity of symptoms, the often overlapping clinical and laboratory characteristics and the pathophysiological changes related to pregnancy make the diagnosis and management of Pr-AKI a difficult and challenging task for the treating physician. In addition to general supportive management strategies such as volume substitution, blood pressure control, prevention of seizures or immediate delivery, each disease entity requires a specific therapy to reduce maternal and fetal complications. In this review, we used the current literature to provide a summary of the physiologic and pathophysiologic changes in renal physiology which occur during pregnancy. In the second part, we present common and rare disorders which lead to Pr-AKI and provide an overview of the available treatment options.

The Importance of Cardiovascular Risk Assessment and Pregnancy Heart Team in the Management of Cardiovascular Disease in Pregnancy

Pregnancy-related maternal morbidity and mortality is increasing because of complications from cardiovascular disease. Pregnancy results in physiologic changes that can adversely impact the cardiovascular system and lead to adverse pregnancy outcomes. A multidisciplinary pregnancy heart team is essential to safely navigate women with heart disease through pregnancy. This role of the pregnancy heart team is to offer preconception counseling, determine pregnancy risks and educate women about those risks, develop a comprehensive antenatal and delivery plan, and ensure appropriate postpartum follow-up. These steps are important to improve cardiovascular outcomes in pregnancy.

Retinal Vascular Changes during the Menstrual Cycle Detected with Optical Coherence Tomography Angiography

Purpose

To evaluate the effects of the menstrual cycle on the retinal vascular status of healthy women by optical coherence tomography angiography (OCTA).

Materials and Methods

Healthy women with regular natural menstrual cycles of 28 to 30 days were recruited for this prospective study. The women's retinal vascular status was measured by OCTA at 3 time points: the early follicular, ovulatory, and midluteal phases of the menstrual cycle. The main outcome measures were foveal avascular zone (FAZ) parameters, perfusion density (PD) percentage in the superficial retinal capillary plexus (SCP), and PD percentage in the deep retinal capillary plexus (DCP). The mean arterial pressure (MAP), spherical equivalent (SE), best-corrected visual acuity (BCVA), intraocular pressure (IOP), and axial (AL) were also measured in a same menstrual cycle.

Results

In total, 62 right eyes of 62 women were included in the study. The mean age was 27.0 ± 1.73 (range, 24 to 31) years, and the mean menstrual cycle was 28.90 ± 0.84 (range, 28 to 30) days. The mean values of the DCP-PD parameters were significantly decreased in the nasal and inferior ETDRS subfields during the ovulatory phase. The mean DCP-PD in the nasal ETDRS subfield in the early follicular, ovulatory, and luteal phases was 54.11 ± 2.85, 56.39 ± 3.03, and 55.70 ± 3.27, respectively. The mean DCP-PD in the inferior ETDRS subfield in the early follicular, ovulatory, and midluteal phases was 52.90 ± 3.30, 54.86 ± 2.51, and 55.21 ± 2.64, respectively. No significant differences were found in MAP, SE, AL, IOP, FAZ area, or other quadrants of PD parameters, and no significant correlation was found between parameters by OCTA and age, MAP,SE, axial length, or IOP.

Conclusions

The DCP-PD decreased in the nasal and inferior ETDRS subfields during the ovulatory phase in our study. This may indicate the need to consider the menstrual phase when interpreting DCP-PD parameters by OCTA in healthy women.

Hematological Profile of Pregnant Women with Suspected Zika Virus Infection Followed Up at a Referral Service in Manaus, Brazil

The purpose of this paper is to describe the hematological profile of pregnant women with suspected Zika virus (ZIKV) infection followed up at a reference service for infectious diseases in Manaus, Brazil, through a clinical, epidemiological, cross-sectional study of pregnant women with an exanthematic manifestation who looked for care between 2015 and 2017. The participants were 499 pregnant women, classified into four subgroups, according to laboratory confirmation of infections: ZIKV-positive; ZIKV-positive and positive for another infection; positive for another infection but not ZIKV-positive; and not positive for any of the infections investigated. Hematological parameters were analyzed descriptively. The association between maternal infection and the hematological profile, along with the association between the maternal hematological profile and the gestational outcome, were tested. Similar hematic and platelet parameters were observed among pregnant women. However, a significant association was observed between low maternal lymphocyte count and a positive diagnosis for ZIKV (p < 0.001). The increase in maternal platelet count and the occurrence of unfavorable gestational outcome were positively associated. A similar hematic and platelet profile was identified among pregnant women, differing only in the low lymphocyte count among ZIKV-positive pregnant women. Regarding gestational outcomes, in addition to the damage caused by ZIKV infection, altered maternal platelets may lead to unfavorable outcomes, with the need for adequate follow-up during prenatal care.

Allostatic load: Developmental and conceptual considerations in a multi-system physiological indicator of chronic stress exposure

Developmental researchers studying how stress affects health have often focused on specific, individual, physiological parameters such as cortisol. Yet, recent theories of stress biology emphasize that the stress response is multi-faceted and engages distinct yet interconnected physiological systems, including metabolic, immune, and cardiovascular systems that respond to one another. Moreover, advocates of a systems approach also argue that the confluence of changes across several physiological systems presents a health risk, even when one indicator alone is not predictive of health outcomes. Allostatic load is one potential multi-system indicator of stress, capturing the cumulative, physiological burden of chronic stress exposure on the body. At the same time, studying allostatic load during early development raises several issues, including how allostatic load is operationalized, the clinical importance of commonly used biomarkers during distinct periods of development, and the fundamental role of timing. In this review paper, we discuss the potential of allostatic load in the context of studies of stress in developmental science, review developmental studies that have assessed allostatic load, and articulate critical conceptual questions regarding the study of allostatic load during the childhood years.

Early pregnancy reference intervals; 29 serum analytes from 4 to 12 weeks' gestation in naturally conceived and uncomplicated pregnancies resulting in live births

Background Pregnancy introduces major physiological changes that also alter biochemical analytes. Maternal and perinatal health can be optimized by early intervention and therefore, pregnancy-specific reference intervals (RIs) for the local population are warranted. While the second and third trimester-specific changes are well described, the first trimester is less well characterized. We therefore wanted to facilitate early detection of abnormalities by generating first trimester reference values for 29 common analytes. Methods In a prospective early pregnancy (PEP) cohort (2016-2017), 203 pregnant women were recruited from 4 to 8 weeks' gestation. Consecutive blood samples were drawn every 2 weeks until an ongoing second trimester pregnancy (n = 164) or a miscarriage (n = 39) occurred. After exclusion of women with complicated pregnancies or deliveries (n = 42), 122 women were included. The serum samples collected at <6, 6-8, 8-10, 10-12 and >12 weeks' gestation were analyzed for 29 common analytes. Subsequently the RIs were calculated according to the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) recommendations (2.5-97.5th percentiles) and compared with the conventional RIs for non-pregnant women. Results Human chorionic gonadotropin (hCG), progesterone (P4), estradiol (E2), pregnancy-associated plasma protein A (PAPP-A), cancer antigen 125 (CA125), thyroid stimulating hormone (TSH), creatinine (CREA) and albumin (ALB) showed an early pregnancy-dependent change compared with conventional limits. For ALB the change was seen at 5.5 weeks' gestation. Conclusions We report gestational age-specific RIs available from the early part of the first trimester applicable to everyday clinical care of pregnant women. Well-known alterations of RIs seen in later trimesters are also observed in the first.

A Review of the Potential Interaction of Selenium and Iodine on Placental and Child Health

A healthy pregnancy is important for the growth and development of a baby. An adverse pregnancy outcome is associated with increased chronic disease risk for the mother and offspring. An optimal diet both before and during pregnancy is essential to support the health of the mother and offspring. A key mediator of the effect of maternal nutrition factors on pregnancy outcomes is the placenta. Complicated pregnancies are characterized by increased oxidative stress in the placenta. Selenium and iodine are micronutrients that are involved in oxidative stress in placental cells. To date, there has been no comprehensive review investigating the potential synergistic effect of iodine and selenium in the placenta and how maternal deficiencies may be associated with increased oxidative stress and hence adverse pregnancy outcomes. We undertook a hypothesis-generating review on selenium and iodine, to look at how they may relate to pregnancy complications through oxidative stress. We propose how they may work together to impact pregnancy and placental health and explore how deficiencies in these micronutrients during pregnancy may impact the future health of offspring.

Evaluation of the Choroid in Women with Uncomplicated Pregnancy

Purpose

To study the choroid in uncomplicated pregnant women using advanced optical coherence tomography (OCT) imaging and analysis.

Methods

Women with uncomplicated pregnancy in the third trimester (>28 weeks gestational age) and age-matched nonpregnant women were enrolled in this prospective study. All subjects underwent spectral-domain OCT with enhanced depth imaging mode and spectral-domain optical coherent tomography angiography (OCTA). Main outcomes were subfoveal choroidal thickness (SFCT), choroidal vascularity index (CVI), and choriocapillaris flow deficits (CC FD).

Results

Twenty-two eyes of 12 uncomplicated pregnant women and 23 eyes of 15 nonpregnant, female controls were included. The mean age was 32.27 ± 6.96 years for the pregnant group and 30.08 ± 5.49 years for control group (P > 0.05). Mean SFCT was 238.70 ± 82.96 µm in the pregnant group, and 277.40 ± 61.79 µm in the control group. CVI was 67.58% ± 2.45% in the pregnant group and 67.31% ± 2.62% in the control group. The CC FD% was 54.06 ± 3.95 in the pregnant group, and 55.02 ± 3.78 in the control group. There was no significant difference between the pregnant and control groups (P > 0.05) in SFCT, CVI or CC FD.

Conclusions

Although extensive hemodynamic changes occurred with pregnancy, choroidal measurements by OCT and OCTA demonstrated no differences in uncomplicated third-trimester pregnant women compared with nonpregnant controls.

Translational Relevance

The unaltered choroid in uncomplicated third-trimester pregnancy we described allows clinicians to determine whether abnormal choroidal measurements could be used as a biomarker for complications of pregnancy.

Multidisciplinary approach in medicine: successful pregnancy in a patient with hyperinsulinism/hyperammonaemia (HI/HA) syndrome

This case illustrates the importance of multidisciplinary counselling and management of pregnancies in women with complex medical conditions, especially concerning women with cognitive impairment. We present a woman with hyperinsulinism/hyperammonaemia (HI/HA) syndrome. This syndrome is characterised by recurrent episodes of hypoglycaemia and elevated ammonia levels, which are potentially harmful to both the patient and a developing fetus. We describe a successful multidisciplinary approach during the pregnancy of a mentally challenged patient with HI/HA syndrome. This case illustrates the importance of personalised counselling during the preconception period and emphasises to include all disciplines involved in the medical and daily care of such a patient. In our case, the extensive multidisciplinary care during the preconception period, pregnancy, delivery and postpartum period resulted in a good maternal and neonatal outcome.

Feeding Buttermilk-Derived Choline Forms During Gestation and Lactation Modulates Ex Vivo T-Cell Response in Rat Dams

BACKGROUND

Buttermilk contains a mixture of choline forms; it is high in phosphatidylcholine (PC) and sphingomyelin (SM), which could have an impact on immune system development and function.

OBJECTIVES

We aimed to determine the effect of feeding buttermilk-derived choline forms during pregnancy and lactation on maternal immune function.

METHODS

Sprague Dawley dams (n = 8 per diet) were randomly assigned midway through pregnancy (10 d of gestation) to 1 of 3 experimental diets, containing 1.7 g/kg choline: control [100% free choline (FC)]; buttermilk [37% PC, 34% SM, 17% glycerophosphocholine (GPC), 7% FC, 5% phosphocholine]; or placebo (50% PC, 25% FC, 25% GPC). Dams consumed the same diet until the end of the lactation period (21 d after parturition). Cell phenotypes and cytokine production by mitogen-stimulated splenocytes were measured and compared using 1-factor ANOVA test in order to asses the effect of diet on immune fuction of lactating dams (main outcome).

RESULTS

After ConA stimulation, splenocytes from dams in the buttermilk group produced more IL-2 (30%), TNF-α (30%), and IFN-γ (42%) compared with both the placebo and control diets. Placebo-fed dams had a higher proportion of CD8+ cells expressing CD152+ (22%) in spleen, and splenocytes from dams that were fed the buttermilk and the placebo diets produced about 50% and 53% more IL-10 after LPS and OVA stimulation, respectively, compared with the control group.

CONCLUSIONS

Feeding buttermilk-derived choline forms during pregnancy and lactation had a beneficial impact on the immune system of Sprague Dawley rat dams, especially on T-cell function.

Salivary proteome signatures in the early and middle stages of human pregnancy with term birth outcome

The establishment and maintenance of pregnancy in humans proceed through a continuous change of biochemical and biophysical processes. It requires a constant interaction between the fetus and the maternal system. The present prospective study aims to elucidate changes in salivary proteome from the early to middle stages of term pregnancy, and establishing an expressional trajectory for modulated proteins. To date, a comprehensive characterization of the longitudinal salivary proteome in pregnancy has not been performed and it is our immediate interest. In the discovery phase, maternal saliva (N = 20) at 6–13, 18–21, and 26–29 weeks of gestation was analyzed using level-free proteomics (SWATH-MS) approach. The expression levels of 65 proteins were found to change significantly with gestational age and distributed into two distinct clusters with a unique expression trajectory. The results revealed that altered proteins are involved in maternal immune modulation, metabolism, and host defense mechanism. Further, verification of 12 proteins was employed using targeted mass spectrometry (MRM-MS) in a separate subset of saliva (N = 14). The MRM results of 12 selected proteins confirmed a similar expression pattern as in SWATH-MS analysis. Overall, the results not only demonstrate the longitudinal maternal saliva proteome for the first time but also set the groundwork for comparative analysis between term birth and adverse pregnancy outcomes.

Statistical Modelling Outcome of In Vitro Fertilization and Intracytoplasmic Sperm Injection: A Single Centre Study

BACKGROUND

Assisted reproductive techniques (ART) have been extensively used to treat infertility. Inaccurate prediction of a couple's fertility often leads to lowered self-esteem for patients seeking ART treatment and causes fertility distress.

OBJECTIVE

This prospective study aimed to statistically analyze patient data from a single reproductive medical center over a period of 18 months, and to establish mathematical models that might facilitate accurate prediction of successful pregnancy when ART are used.

METHODS

In the present study, we analyzed clinical data prospectively collected from 760 infertile patients visiting the second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University between June 1, 2016 and December 31, 2017. Various advanced statistical methods, including broken-line regression, were employed to analyze the data.

RESULTS

Age remained the most important factor affecting the outcome of IVF/ICSI. Using the broken-line regression model, the fastest clinical pregnancy declining age was between 25 and 32. Female infertility type was found to be a key predictor for the number of good-quality embryos and successful pregnancy, along with the antral follicle count (AFC), total number of embryos, recombinant follicle stimulating hormones (rFSH) dosage, estradiol (E2) on the trigger day, and total number of oocytes retrieved. rFSH dosage was also significantly associated with the number of oocytes retrieved and the number of frozen embryos.

CONCLUSION

The fastest clinical pregnancy declining age is ranged between 25 and 32, and female infertility type is evidenced as another key predictive factor for the cumulative outcome of ART.

Prenatal Biochemical Screening and a Woman’s Long-Term Risk of Cancer: A Population-Based Cohort Study

Background

Some hormones measured in pregnancy are linked to certain hormone-sensitive cancers. We investigated whether routine serum screening in pregnancy is associated with a woman’s subsequent risk of hormone-sensitive cancer.

Methods

This population-based cohort study included women aged 12–55 years who underwent prenatal screening between 11 weeks + 0 days of gestation to 20 weeks + 6 days of gestation in Ontario, Canada, 1993–2011, where universal health care is available. The hazard ratio of newly diagnosed breast, ovarian, endometrial, and thyroid cancer—arising at 21 weeks + 0 days of gestation or thereafter—was estimated in association with an abnormally low (≤5th) or high (>95th) percentile multiple of the median (MoM) for alpha-fetoprotein (AFP), total human chorionic gonadotropin (hCG), unconjugated estriol, pregnancy-associated plasma protein A, and dimeric inhibin A.

Results

Among 677 247 pregnant women followed for a median of 11.0 years (interquartile range = 7.5–16.1), 7231 (1.07%) developed breast cancer, 515 (0.08%) ovarian cancer, 508 (0.08%) endometrial cancer, and 4105 (0.61%) thyroid cancer. In multivariable adjusted models, abnormally high hCG greater than the 95th percentile MoM was associated with a doubling in the risk of endometrial cancer (adjusted hazard ratio [aHR] = 1.98, 95% confidence interval [CI] = 1.33 to 2.95), and abnormally low AFP at the fifth percentile or less MoM conferred a moderately greater risk of thyroid cancer (aHR = 1.21, 95% CI = 1.07 to 1.38). Abnormally low pregnancy-associated plasma protein A at the fifth percentile or less MoM was not statistically significantly associated with breast cancer after multivariable adjustment (aHR = 1.19, 95% CI = 0.98 to 1.36).

Conclusions

Women with abnormally high levels of serum hCG or low AFP in early pregnancy may be at a greater future risk of certain types of hormone-sensitive cancers.

To Evaluate Choroidal and Retinal Thicknesses in Singleton versus Twin Pregnancies using Optical Coherence Tomography

PURPOSE:

The purpose of the study was to evaluate the choroidal and retinal thicknesses in singleton versus twin pregnancies.

MATERIALS AND METHODS:

This study included 20 single and 20 twin pregnant women in their 3^rd trimester with 20 age-matched healthy nonpregnant women as a control group. All participants underwent a detailed ocular examination. Cirrus enhanced depth imaging-optical coherence tomography was used for choroidal thickness (CT) with frame enhancement software. The study was divided into three groups: Group 1 – singleton pregnancy, Group 2 – twin pregnancy, and Group 3 – healthy nonpregnant controls. CT was measured from nasal, subfoveal, and temporal fields.

RESULTS:

Regarding CT, the twin pregnancy group had the thickest choroid followed by the singleton pregnancy group and control group. There was a statistically significant difference between Group 2 and Group 3 in terms of nasal, subfoveal, and temporal CTs (P = 0.002, P = 0.001, and P = 0.003, respectively). There was a statistically significant difference between Group 1 and Group 3 regarding just subfoveal CT (P = 0.028). Regarding retinal thickness, there was a statistically significant difference between Group 1 and Group 3 regarding the mean macular volume and ganglion cell-inner plexiform layer thicknesses (P < 0.05). Furthermore, regarding mean retinal nerve fiber layer thickness, there was a statistically significant difference between Group 1 and Group 2 and between Group 2 and Group 3 (P = 0.004, P = 0.003, respectively).

CONCLUSION:

Our study is the first one which evaluates choroidal and retinal thicknesses in twin pregnancies. We found that there was an increase in CT in the 3^rd trimester of pregnancies and it was prominent in twin pregnancies.

Postpartum care of women with renal disease

Twenty-three percent of women with known chronic kidney disease (CKD) have been reported to demonstrate the first decline in kidney function between giving birth and six-weeks postpartum. As such, these women warrant close monitoring during the postpartum period irrespective of their pregnancy journey. Substantial haemodynamic variability during pregnancy and postpartum renders estimated glomerular filtration rate inaccurate, and poorly defined normal ranges of markers of kidney function at this time pose challenges for accurate assessment of renal complications. Multi-disciplinary specialist care is therefore essential, with consideration of specific implications of any known renal diagnosis and with observation for the development of postpartum complications of pregnancy. Furthermore, the postpartum period affords time to further investigate and diagnose kidney disease revealed by pregnancy. Good care planning and communication in the postpartum period has the potential to improve long-term health outcomes for women with known or new CKD and will be discussed in this review.

Hormone Levels in Pregnancy and Subsequent Risk of Maternal Breast and Ovarian Cancer: A Systematic Review

OBJECTIVE

Some maternal hormone levels in pregnancy are associated with a higher risk of breast and ovarian cancer. This study systematically assessed the association between blood hormone levels measured in pregnancy and future risk of these cancers.

METHODS

Two reviewers independently conducted a literature search of MEDLINE and EMBASE databases from January 1970 to August 2017. Studies were included that measured one or more serum hormone levels in pregnancy and later assessed for cancer. Cancer outcomes were considered by cancer type, each in relation to a specific maternal hormone.

RESULTS

Eleven studies were included, comprising a total of 57 967 women. The interval between pregnancy and cancer onset varied from 4.1 to 20.5 years. Elevated serum chorionic gonadotropin (two of four studies) and alpha fetoprotein (two of three studies) were each associated with a lower risk of maternal breast cancer, whereas elevated estrone levels suggested a higher risk (one of three studies). Elevated testosterone (one of one study) and androstenedione (one of one study) were each associated with a significantly greater risk of sex-cord stromal ovarian tumours. Higher serum 17-hydroxyprogesterone was associated with an increased risk of sex-cord stromal (one of one study) and epithelial (one of one study) ovarian cancer.

CONCLUSION

Observational studies suggest some degree of association between serum hormones measured in pregnancy and a woman's future risk of breast and ovarian cancer. More data are needed to determine sufficiently whether certain blood hormone levels measured in pregnancy are predictive of future cancer risk.

Physiological changes in pregnancy

Physiological changes occur in pregnancy to nurture the developing foetus and prepare the mother for labour and delivery. Some of these changes influence normal biochemical values while others may mimic symptoms of medical disease. It is important to differentiate between normal physiological changes and disease pathology. This review highlights the important changes that take place during normal pregnancy.

Updated Etiology and Significance of Elevated Bilirubin During Pregnancy: Changes Parallel Shift in Demographics and Vaccination Status

BACKGROUND

The most common cause of jaundice during pregnancy in the United States (US) is still attributed to viral hepatitis, despite the dramatic drop in incidence of viral hepatitis in the US.

OBJECTIVE

We hypothesized that viral hepatitis is no longer a frequent etiology of jaundice among the pregnant population in the US and sought to identify the contemporary causes of elevated bilirubin during pregnancy as well as to quantify the associated risk to the mother and fetus.

STUDY DESIGN

Clinical data from all pregnant women who delivered an infant between 2005 and 2011 at a single hospital in Dallas, Texas, were ascertained using prospectively collected computerized databases. Women with elevated total bilirubin (>1.2 mg/dl) were analyzed to determine the cause of hyperbilirubinemia and maternal and fetal outcomes.

RESULTS

Out of a total of 80,857 consecutive deliveries, there were 397 (0.5 %) pregnancies with hyperbilirubinemia. The most common etiology was gallstones (98/397 = 25 %), followed by preeclampsia/eclampsia/HELLP (94/397 = 24 %) and intrahepatic cholestasis of pregnancy (53/397 = 13 %). Adverse infant outcomes, including stillbirths, fetal malformations, neonatal deaths, and small for gestational age births, were more common in the women with hyperbilirubinemia during pregnancy, but there were no maternal deaths.

CONCLUSIONS

Acute viral hepatitis is no longer a common cause of jaundice in pregnant women in the US. In the current era, gallstones and preeclampsia-related disorders are the most common causes of jaundice in pregnant women. Disorders that cause elevated maternal bilirubin during pregnancy are associated with increased risk for the fetus.

Renal and Hepatic Functions after A Week of Controlled Ovarian Hyperstimulation during In Vitro Fertilization Cycles

BACKGROUND

One the main aspects of in vitro fertilization (IVF) cycle is to avoid any possible systemic damage on women undergoing a controlled ovarian hyperstimulation (COH). The aim of this work is to evaluate renal and hepatic function blood tests in patients undergoing controlled ovarian hyperstimulation during IVF cycles.

MATERIALS AND METHODS

We performed a prospective cohort analysis. All patients re- ceived a long stimulation protocol with gonadotropin-releasing hormone (GnRH) analogues by daily administration, since the twenty-first day of the previous ovarian cycle followed by COH with recombinant follicle-stimulating hormone (FSH). The daily dose of exogenous gonadotropins for every single patient was modified according to her follicular growth. The oocytes were retrieved during the oocyte pick up and fertilized by standard procedures of intracytoplasmic sperm injection (ICSI). The blood samples to evaluate renal and hepatic functions were taken at the 7^th day of ovarian stimulation.

RESULTS

We enrolled 426 women aged between 19 and 44 years, with a mean body mass index (BMI) of 24.68 Kg/m². The mean value of blood urea nitrogen was 14 ± 3.16 mg/ dl, creatinine: 1 ± 0.45 mg/dl, uric acid: 4 ± 1.95 mg/dl, total proteins: 7 ± 3.93 mg/dl, aspartate aminotransferase: 18 ± 6.29 mU/ml, alanine aminotransferase: 19 ± 10.41 mU/ ml, alkaline phosphatase: 81 ± 45.25 mU/ml, total bilirubin 1 ± 0.35 mg/dL. All of the results were considered as a normal range following the Medical Council of Canada.

CONCLUSION

Our data suggest that, unlike ovarian hyperstimulation syndrome (OHSS), COH patients did not show any alteration to renal and hepatic functions.

Physiologic and pharmacokinetic changes in pregnancy

Physiologic changes in pregnancy induce profound alterations to the pharmacokinetic properties of many medications. These changes affect distribution, absorption, metabolism, and excretion of drugs, and thus may impact their pharmacodynamic properties during pregnancy. Pregnant women undergo several adaptations in many organ systems. Some adaptations are secondary to hormonal changes in pregnancy, while others occur to support the gravid woman and her developing fetus. Some of the changes in maternal physiology during pregnancy include, for example, increased maternal fat and total body water, decreased plasma protein concentrations, especially albumin, increased maternal blood volume, cardiac output, and blood flow to the kidneys and uteroplacental unit, and decreased blood pressure. The maternal blood volume expansion occurs at a larger proportion than the increase in red blood cell mass, which results in physiologic anemia and hemodilution. Other physiologic changes include increased tidal volume, partially compensated respiratory alkalosis, delayed gastric emptying and gastrointestinal motility, and altered activity of hepatic drug metabolizing enzymes. Understating these changes and their profound impact on the pharmacokinetic properties of drugs in pregnancy is essential to optimize maternal and fetal health.

Association between low blood glucose increase during glucose tolerance tests in pregnancy and impaired fetal growth

OBJECTIVE

To evaluate how different levels of increase in maternal blood glucose from a fasting state to 2 h after an oral glucose challenge in late pregnancy are associated with fetal growth, with special emphasis on those with a low increase.

DESIGN

Prospective cohort study.

SUBJECTS

We followed 855 women, of whom 70% had an increased risk for carrying lighter babies.

STUDY DESIGN AND METHODS

Ultrasound was used to estimate fetal growth in gestational weeks 25, 33 and 37. In week 37 the women had a 75-g oral glucose tolerance test, and fasting and 2-h capillary glucose values were recorded with the difference between these two called delta (∆) glucose. Three groups were constructed from the ∆ glucose distribution: Low below the 10th centile; Medium between the 10th and 90th centiles; and High above the 90th centile. Missing data were imputed. Linear and Poisson regression models were applied.

OUTCOME MEASURES

Estimated fetal weight, percent deviation from expected fetal weight and anthropometric measures at birth.

RESULTS

The Low group carried the lightest fetuses and the High group the heaviest. The fetal growth in the Low group deviated increasingly more in a negative direction from week 25 to 37 than in the other groups.

CONCLUSION

In a high-risk population, a positive relation between ∆ glucose and fetal growth was found. The Low group demonstrated impaired growth. More attention should be paid to pregnant women with an insufficient increase in glucose after a glucose challenge. Future studies should challenge our findings in high-risk and low-risk populations.

Allostatic load may not be associated with chronic stress in pregnant women, NHANES 1999-2006

PURPOSE

Pregnant women are generally excluded from studies that measure allostatic load (AL) because there is concern that the changing levels of AL-related biomarkers during pregnancy do not reflect a woman's true AL. The goal of this study was to determine whether AL can be measured in a meaningful way during pregnancy.

METHODS

The National Health and Nutrition Examination Survey (NHANES) is a nationally representative, cross-sectional survey of the U.S. civilian population. AL was based on the distributions of 10 biomarkers in pregnant (n = 1138) and nonpregnant (n = 4993) women aged 15 to 44 from NHANES (1999-2006).

RESULTS

The distribution of each AL-related biomarker differed significantly between pregnant and nonpregnant women (P < .01). Among nonpregnant women, high AL findings were consistent with previous studies (e.g., higher AL in women who are black, are older, and who have lower incomes). However, these associations were not seen in pregnant women.

CONCLUSIONS

Our results suggest that the various biomarkers that comprise AL may reflect proximal factors in pregnancy more strongly than they represent exposure to chronic stress over a woman's lifetime. Therefore, our approach to measuring AL may not provide meaningful information about chronic stress in pregnant women without further consideration of pregnancy-related factors.

Vitamin E deficiency in developing countries

In addition to its role as a potent antioxidant, vitamin E is involved in a wide range of physiological processes, ranging from immune function and control of inflammation to regulation of gene expression and cognitive performance. Results from multiple studies suggest that poor nutritional status and higher prevalence of other oxidative stressors such as malaria and HIV infection predispose populations in developing countries for vitamin E deficiency. Although direct comparison between study outcomes is complicated by varied definitions of vitamin E deficiency, data trends indicate that children and the elderly are more vulnerable age groups and that men may be at higher risk for deficiency than women. Public health initiatives aimed at improving the vitamin E status of high-risk populations in developing countries would be prudent to counteract oxidative stress, improve immune function, and protect against neurologic and cognitive deficits. Additional research is needed to establish dose-response relationships of various interventions and to develop cost-effective, culturally-appropriate, and targeted programs.

Changes in transferrin glycosylation during pregnancy may lead to false-positive carbohydrate-deficient transferrin (CDT) results in testing for riskful alcohol consumption

BACKGROUND

An alcohol-induced change in serum transferrin glycosylation, termed carbohydrate-deficient transferrin (CDT), is widely used as a biomarker of heavy long-term drinking. This study examined the transferrin glycosylation profile and the risk for false-positive CDT results during pregnancy.

METHODS

Serum samples were collected from 24 healthy pregnant women starting in gestation week 9-21, throughout pregnancy, and 8 or more weeks after delivery. Altogether 171 sera (5-9 samples/person) were analysed. Transferrin glycoforms were quantified as a percentage of total transferrin, using an HPLC candidate reference method for CDT.

RESULTS

During pregnancy, the relative disialo-, pentasialo- and hexasialotransferrin levels increased gradually, whereas trisialo- and tetrasialotransferrin were reduced. This effect was most pronounced in the third trimester. For disialotransferrin, the main target in CDT testing, initial values of 1.07 ± 0.17% (mean ± SD) increased to 1.61 ± 0.23% before delivery (~50% increase). Nine (38%) pregnant women reached %disialotransferrin values ≥ 1.7% (97.5th percentile for controls) but all results were < 2.0%. In the postpartum samples, all glycoform levels had returned towards the starting values.

CONCLUSIONS

These results suggest that the cutoff for %disialotransferrin and %CDT employed to indicate heavy long-term drinking need to be raised slightly in pregnant women, to minimize the risk for false-positive results on CDT testing.

Dichlorodiphenyldichloroethane and polychlorinated biphenyls: intraindividual changes, correlations, and predictors in healthy women from the southeastern United States

Dichlorodiphenyldichloroethane (DDE) and polychlorinated biphenyls (PCB) are widespread environmental contaminants that have been postulated to increase the risk of diseases such as non-Hodgkin's lymphoma, breast cancer, as well as lead to early menopause. Studies assessing the effect of organochlorine exposure often can only measure organochlorine levels once, such as at study enrollment, which may not be an etiologically relevant time period. We assessed the temporal changes in DDE and PCBs and the predictors of those changes using interview data and DDE and PCB measures collected from 123 women who were enrolled in a baseline study from 1978 to 1982 and followed up in 2003 to 2004. Baseline and follow-up organochlorine levels were compared using Spearman correlations (r(s)), and predictors of the rate of change in log concentration were evaluated using linear regression models. Although serum concentrations dramatically declined (median follow-up to baseline concentration ratio was 16% for DDE and 45% for PCB), baseline and follow-up measures were strongly correlated for DDE (r(s)=0.72) and moderately correlated for PCBs (r(s)=0.43). Prediction of follow-up PCB levels was substantially improved (r(s)=0.75) with data on initial concentration, length of lactation, baseline body mass index, and percent change in body fat, whereas DDE prediction improved slightly (r(s)=0.83) with data on lactation and baseline body mass index. These findings suggest that a single organochlorine measure provides considerable information on relative ranking at distant times and that the predictive power can be improved, particularly for PCBs, with information on a few predictors.

Best practice in primary care pathology: review 9

This ninth best-practice review examines two series of common primary care questions in laboratory medicine: (i) potassium abnormalities and (ii) venous leg ulcer microbiology. The review is presented in question-and-answer format, referenced for each question series. The recommendations represent a précis of guidance found using a standardised literature search of national and international guidance notes, consensus statements, health policy documents and evidence-based medicine reviews, supplemented by MEDLINE EMBASE searches to identify relevant primary research documents. They are not standards but form a guide to be set in the clinical context. Most are consensus rather than evidence-based. They will be updated periodically to take account of new information.

The role of the endocannabinoid system in gametogenesis, implantation and early pregnancy

Maternal use of marijuana, in which the exocannabinoid Delta(9)-tetrahydrocannabinol is the most active psychoactive ingredient, is known to have adverse effects on various aspects of reproduction including ovulation, spermatogenesis, implantation and pregnancy duration. Endogenous cannabinoids of which Anandamide is the prototype are widely distributed in the body especially in the reproductive tract and pregnancy tissues and act through the same receptors as the receptor as Delta(9)-tetrahydrocannabinol. Anandamide, has been reported to have pleiotropic effects on human reproduction and in experimental animal models. It appears to be the important neuro-cytokine mediator synchronizing the embryo-endometrial development for timed implantation, the development of the embryo into the blastocyst and transport of the embryo across the fallopian tubes. The mechanisms by which it exerts these effects are unclear but could be via direct actions on the various sites within the reproductive system or its differential actions on vascular tone dependent. In this review article we bring together the current knowledge on the role of endoccanabinoids in reproduction and postulate on the potential mechanisms on how these affect reproduction. In addition, we examine its role on the endothelium and vascular smooth muscle as a potential mechanism for adverse pregnancy outcome.

Biochemistry testing associated with pregnancy and the newborn period -- a lot has changed since you were a baby!

Everyone has been a newborn, and everyone's mother has been pregnant. Despite the commonality of these events, medical care and the clinical chemistry laboratory's role in it have changed remarkably over the last 50 years. This review is a historical overview of clinical chemistry testing that is related to pregnancy and the newborn period.

Status of anti-thyroid peroxidase during normal pregnancy and in patients with hyperemesis gravidarum

Autoimmune thyroid diseases (AITD) comprising Hashimoto's thyroiditis, primary myxedema, and Graves' disease are associated with autoantibodies directed against thyroglobulin and thyroid peroxidase (anti-TPO). Anti-TPO occur in 10% of pregnant women, half of whom reportedly develop postpartum thyroid dysfunction. We recently published data on the thyroid function reference ranges in pregnant Chinese but the AITD status of our cohort was unknown. In view of this missing information we have measured anti-TPO in specimens from our cohort stored at -80 degrees C, and compared these to those of patients with hyperemesis gravidarum (HG) and nonpregnant controls. After eliminating 3 outliers from 47 nonpregnant controls, the anti-TPO concentration range was 2.2-14.7 kIU/L (n = 44). In 282 pregnant control subjects, the anti-TPO levels were less than 14.7 kIU/L (upper limit of nonpregnant controls) in 189 (67%); between 14.7-55 kIU/L in 82 (29.1%); and greater than 55 kIU/L in 11 (3.9%). The percentage of women with anti-TPO greater than 14.7 kIU/L during the first, second, and third trimesters were 47% (30/64), 39% (49/126), and 16% (15/92), respectively. Anti-TPO level was significantly higher in pregnant controls compared to nonpregnant controls and patients with HG. With reference to other studies in which anti-TPO levels greater than 60 kIU/L were considered pathologic, we conclude that more than 96% of our pregnant controls were without AITD and the data on thyroid function reference ranges we previously reported remain valid.

Olestra is associated with slight reductions in serum carotenoids but does not markedly influence serum fat-soluble vitamin concentrations

BACKGROUND

The 1996 Food and Drug Administration approval of the fat substitute olestra (sucrose polyester) called for active postmarketing surveillance because preapproval studies showed that olestra may lower circulating concentrations of fat-soluble nutrients such as vitamins and carotenoids.

OBJECTIVE

The objective of the Olestra Post-Marketing Surveillance Study was to examine whether customary consumption of olestra-containing savory snacks was associated with changes in serum fat-soluble vitamin and carotenoid concentrations among free-living persons in geographically and ethnically distinct US cities.

DESIGN

Adults (n = 2535) and their children aged 12-17 y (n = 272) in Baltimore, Minneapolis, and San Diego attended clinic visits during which data were collected on diet, savory snack consumption, lifestyle, and anthropometric indexes. Blood samples were drawn to assay carotenoids and vitamins A, D, E, and K. Data and blood samples were collected both before and after the nationwide introduction of olestra. General estimating equations were used in multivariate-adjusted models that examined olestra's association with the specified serum nutrients.

RESULTS

Compared with no intake, the top 2 tertiles of olestra use in adults were associated with circulating carotenoid concentrations that were modestly but significantly lower (4.3% to 22.4%). There were no significant associations of olestra with any serum nutrients among adolescents.

CONCLUSIONS

This active postmarketing surveillance study of a food additive suggests that small decreases in serum fat-soluble nutrients are attributable to olestra use. Although health outcomes were not measured here, it is unlikely that these small changes in nutrient measures would adversely affect health.

Female sex steroids increase adrenomedullin-induced vasodilation by increasing the expression of adrenomedullin2 receptor components in rat mesenteric artery

Based on the favorable effects of female sex steroids in vascular functions and the potent hypotensive effects of adrenomedullin (AM), we hypothesized that AM-induced vasodilation is gender dependent, and female sex steroids enhance this effect. In endothelium-intact rat mesenteric artery, AM (1 nm-0.3 microM)-induced concentration-dependent relaxation was significantly (P < 0.05) higher in females [pD2(-log EC50 of the molar concentration), 7.05 +/- 0.10; maximal relaxation response (Emax), 69.2 +/- 3.46%] than males (pD2, 6.53 +/- 0.08; Emax, 53.28 +/- 4.86%). The increased relaxation was lost when the females were ovariectomized (OVX) (pD2, 6.14 +/- 0.24; Emax, 39.68 +/- 5.68%). The reduced relaxation response in OVX rats was reversed by administration of either progesterone (P4; pD2, 7.18 +/- 0.07; Emax, 72.4 +/- 2.76%) or 17beta-estradiol (E2; pD2, 7.00 +/- 0.14; Emax, 70.4 +/- 4.79%). AM mediates its effects through either AM(22-52)-sensitive AM1 receptors [composed of calcitonin receptor-like receptors (CLs) and receptor activity-modifying protein (RAMP)2] or AM2 receptors (CL/RAMP3), which can be antagonized more potently by calcitonin gene-related peptide(8-37) than AM(22-52). Pharmacological characterization suggested the involvement of AM2 receptors in the increased vasodilatory effect of AM in both P4- and E2-treated animals as calcitonin gene-related peptide(8-37) (10 microM) was more potent in antagonizing the AM effects (Emax, P(4): 25.92 +/- 5.32%; E2: 29.11 +/- 7.41%) than AM(22-52) (100 microM). RT-PCR studies also supported the involvement of AM2 receptors because expression of mRNA levels encoding CL (previously reported) and RAMP3 were increased in P4- or E2-treated OVX rats. In conclusion, AM-induced vasodilation is gender-dependent and increased by female sex steroids by increased expression of AM2 receptor components.

The concentration of free holo-retinol binding protein is higher in vitamin A-sufficient than in deficient Nepalese women in late pregnancy

Free holo-retinol binding protein (RBP) [i.e., unbound to transthyretin (TTR)] plays a role in transporting vitamin A across the placenta during pregnancy. In a cross-sectional study of clinically healthy urban women, we assessed the association among clinical and biochemical factors on estimated concentrations of free holo-RBP during the last trimester of pregnancy. Serum samples obtained from a subsample of women (n = 259), who had participated in the Night Vision Threshold Test study in Nepal, were analyzed for determinations of retinol by HPLC, and RBP, TTR, and alpha-1 acid glycoprotein by radial immunodiffusion. Free holo-RBP concentrations were calculated using dissociation constants for free holo- and apo-RBP. Among these women, 30% were vitamin A deficient based on either the RBP:TTR index < or = 0.36 or serum retinol < 1.05 micromol/L. Using stepwise regression analyses, the RBP:TTR index explained 75% of the variance in free holo-RBP concentrations, whereas retinol explained only 14%. Women were classified as vitamin A sufficient (n = 185) or deficient (n = 74) using the RBP:TTR index and were stratified into 3 gestational groups (I: 24-28 wk, II: 29-33 wk, III: >33 wk). Concentrations of free holo-RBP were higher in vitamin A-sufficient women than in vitamin A-deficient women (mean +/- SEM, 48.1 +/- 1.2 vs. 27.6 +/- 0.8 nmol/L; P < 0.001), and in a 3 x 2 factorial analysis, the interaction between gestational group and vitamin A status was significant. These results demonstrate that the RBP:TTR index is a useful proxy for free holo-RBP concentration and that vitamin A status affects its distribution.

Thyroid hormones status during pregnancy in normal Iranian women

Pregnancy is associated with significant, but reversible changes in thyroid function studies, which are among the most profound seen as a result of a normal physiologic state. The present study was carried out to find out alterations in thyroid function tests in each trimester in normal pregnant women as compared to non-pregnant women in Tabriz-Iran. A case-control study designed with 229 normal pregnant women that randomly selected from the first (64 samples), the second (92 samples), and the third (73 samples) trimesters and 250 randomly selected non-pregnant healthy female controls. Age range in both groups was 16-40 years. Thyroid function tests carried out by measuring serum levels of thyroid stimulating hormone (TSH), free and total thyroxin (FT(4), TT(4)), and free and total triiodothyronine (FT(3), TT(3)) by commercially available radio immunoassay kits. We found that mean TT(4) increased progressively during pregnancy. Our study showed increasing in serum levels of TT(3) in the second trimester and then declining during the third trimester compared with non-pregnant women. We showed that FT(4) strongly decreased during the third trimester. Free T(3) showed declining in the second and third trimesters. Mean TSH did not show significant difference in each trimester compared with non-pregnant women. The thyroid function tests in pregnancy should be interpreted against gestational age-related reference intervals to avoid mis-interpretation of thyroid function during pregnancy.

Maternal-fetal risk assessment

In first-world countries, maternal and infant mortality has significantly decreased over the past 50 years due to factors such as skilled pregnancy care practitioners, aseptic hospital births, antibiotics, safe blood transfusions, and oxytocin. However, international maternal and infant mortality statistics from underdeveloped countries remain high. Pregnancy risk management requires implementation of risk-reduction strategies that have been proven to be effective. Marked physiological alterations in biochemical indices that occur in pregnancy require that laboratories participating in the evaluation of new interventions in pregnancy must ensure that tests are compared to appropriate gestation-specific reference intervals.

Maternal cardiac function during pregnancy at high altitude

OBJECTIVE

To investigate the maternal cardiovascular adaptation in pregnancy at high altitude, compared with that at sea level.

DESIGN

Cross sectional study.

SETTING

Two maternity units providing routine antenatal care: one at 4370 m above sea level (Cerro de Pasco, Peru) and one at sea level (Lima, Peru).

POPULATION

We examined 175 pregnant women at 5-41 weeks of gestation and 16 non-pregnant controls resident at high altitude and 132 pregnant women and 18 non-pregnant controls at sea level.

METHODS

Two-dimensional and M-mode echocardiography of the left ventricle.

MAIN OUTCOME MEASURES

Maternal cardiac output and left ventricular longitudinal and transverse systolic function indices.

RESULTS

Pregnancy at high altitude, compared with sea level, is associated with 11% lower birthweight and 31% lower maternal cardiac output, due to 15% lower stroke volume and 11% lower heart rate. The lower stroke volume was due to a lower preload and impaired longitudinal and transverse left ventricular systolic function. Mean arterial pressure was about 8% lower during pregnancy at high altitude versus sea level. Pregnant women at high altitude failed to expand their intravascular space to the same extent as the sea level group: cardiac output increased by 17%, left atrial diameter by 12% and end-diastolic diameter by 1% at high altitude versus 41%, 25% and 5%, respectively, at sea level.

CONCLUSIONS

Pregnancy at high altitude, compared with sea level, is characterised by lower cardiac output due to lower heart rate and lower stroke volume and reduced expansion of the maternal intravascular space compared with the non-pregnant state.