Pregnancy and weaning regulate human maternal liver size and function

Antioxidant Response of Maternal and Fetal Rat Liver to Selenium Nanoparticle Supplementation Compared to Sodium Selenite: Sex Differences between Fetuses

To compare the effects of organic selenium nanoparticles (SeNPs, Se0) and inorganic sodium selenite (NaSe, Na2SeO3, Se4+) on the antioxidant response in maternal and fetal rat liver, pregnant females were treated with two forms of selenium (Se) at equivalent doses during gestation (0.5 mg SeNPs or 0.5 mg NaSe/kg body weight/day). Structural parameters of the liver of gravid females and their fetuses were examined in a sex-specific manner. The oxidative stress parameters superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), glutathione reductase (GR), glutathione S-transferase (GST), total glutathione (GSH) and sulfhydryl groups (SH) were established. In addition, the Se concentration was determined in the blood, liver, urine and feces of the gravid females and in the liver of the fetuses. The structure of the liver of gravid females remained histologically the same after supplementation with both forms of Se, while the oxidative stress in the liver was significantly lower after the use of SeNPs compared to NaSe. Immaturity of fetal antioxidant defenses and sex specificity were demonstrated. This study provides a detailed insight into the differences in the bioavailability of the nano form of Se compared to sodium selenite in the livers of pregnant females and fetuses.

Pharmacokinetics of Monoclonal Antibodies Throughout Pregnancy: A Systematic Literature Review

BACKGROUND AND OBJECTIVE

Although little information is available on the pharmacokinetics (PK) of monoclonal antibodies (mAbs) during pregnancy, multiple mAbs are being used during pregnancy for various indications. The aim of this systematic literature review was to characterize the PK of mAbs throughout pregnancy.

METHODS

A systematic literature search was carried out in PubMed and Embase on 21 April 2023. Articles were included when information on PK or exposure parameters of mAbs in pregnant women was available.

RESULTS

A total of 42 relevant articles were included, of which eight discussed adalimumab, three certolizumab pegol, five eculizumab, one golimumab, 12 infliximab (IFX), two natalizumab, one canakinumab, one omalizumab, five tocilizumab, eight ustekinumab, and five vedolizumab. One of the 42 studies reported information on clearance (CL) and volume of distribution (VD) of IFX; all other studies only reported on serum concentrations in the pre-pregnancy state, different trimesters, and the postpartum period. For all of the assessed mAbs except IFX, serum concentrations were similar to concentrations in the pre-pregnancy state or modestly decreased. In contrast, IFX trough concentrations generally increased in the second and third trimesters in comparison to the non-pregnant state.

CONCLUSION

Available information suggests that the anatomical and physiological changes throughout pregnancy may have meaningful effects on the PK of mAbs. For most mAbs (not IFX), modestly higher dosing (per mg) maybe needed during pregnancy to sustain a similar serum exposure compared to pre-pregnancy.

The Cardiometabolic Impact of Rebaudioside A Exposure during the Reproductive Stage

The consumption of non-sugar sweeteners (NSS) has increased during pregnancy. The European Food Safety Agency suggested that steviol glycosides, such as Rebaudioside A (RebA), the major sweetener component of stevia, are safe for humans up to a dose of 4 mg/kg body weight/day. However, the World Health Organization recommended in 2023 the restraint of using NSS, including stevia, at any life stage, highlighting the need to study NSS safety in early periods of development. We aimed to study the mitochondrial and cardiometabolic effects of long-term RebA consumption during the reproductive stage of the life cycle. Female rats were exposed to RebA (4 mg steviol equivalents/kg body weight/day) in the drinking water from 4 weeks before mating until weaning. Morphometry, food and water consumption, glucose and lipid homeostasis, heart structure, function, and mitochondrial function were assessed. RebA showed an atrophic effect in the heart, decreasing cardiomyocyte cross-sectional area and myocardial fibrosis without repercussions on cardiac function. Mitochondrial and myofilamentary functions were not altered. Glucose tolerance and insulin sensitivity were not affected, but fasting glycemia and total plasma cholesterol decreased. This work suggests that this RebA dose is safe for female consumption during the reproductive stage, from a cardiometabolic perspective. However, studies on the effects of RebA exposure on the offspring are mandatory.

Investigating gastrointestinal disorders in pregnancy

This article reviews anatomical and physiological changes and alterations in reference intervals for laboratory tests in healthy pregnancy, pertinent to investigation of the gastrointestinal system. The safety of procedures and radiological investigations relevant to the investigation of gastrointestinal disorders in pregnancy are also reviewed.

A multi-tissue metabolome atlas of primate pregnancy

Pregnancy induces dramatic metabolic changes in females; yet, the intricacies of this metabolic reprogramming remain poorly understood, especially in primates. Using cynomolgus monkeys, we constructed a comprehensive multi-tissue metabolome atlas, analyzing 273 samples from 23 maternal tissues during pregnancy. We discovered a decline in metabolic coupling between tissues as pregnancy progressed. Core metabolic pathways that were rewired during primate pregnancy included steroidogenesis, fatty acid metabolism, and arachidonic acid metabolism. Our atlas revealed 91 pregnancy-adaptive metabolites changing consistently across 23 tissues, whose roles we verified in human cell models and patient samples. Corticosterone and palmitoyl-carnitine regulated placental maturation and maternal tissue progenitors, respectively, with implications for maternal preeclampsia, diabetes, cardiac hypertrophy, and muscle and liver regeneration. Moreover, we found that corticosterone deficiency induced preeclampsia-like inflammation, indicating the atlas's potential clinical value. Overall, our multi-tissue metabolome atlas serves as a framework for elucidating the role of metabolic regulation in female health during pregnancy.

Bile acids metabolism in the gut-liver axis mediates liver injury during lactation

AIMS

The obesity epidemic, especially in pregnant women, linked to a higher risk of liver diseases. Bile acids (BAs) are known to participate in liver metabolism, but this function during obesogenic reproductive process remains largely uncertain. The study aims to identify whether a high-fat diet (HFD) during pregnancy negatively disturbs liver metabolism and the potential role of BAs and gut microbiota (GM)in a sow model.

MAIN METHODS

Reproductive (RP) or non-reproductive (NRP) sows were fed a 15 % HFD containing compound oil. Body condition, blood parameters, and BAs levels/profile during gestation and lactation were monitored. The tissues and colonic GM were collected after euthanasia at the end of lactation. HepG2 hepatocytes were used to test the effects of BAs on liver damage and the mechanism.

KEY FINDINGS

Reproductive sows fed an HFD (HF-RP) experienced increased weight loss, and elevated plasma non-esterified fatty acid (NEFA) during lactation, consistent with exacerbated lipolysis, aggravating the risk of liver damage. HF-RP sows exhibited an enlarged BAs pool size and alterations in composition (higher levels of CDCA and LCA species) along with a drastic change in the GM (increased Firmicutes/Bacteroidetes ratio and declined Lactobacillus abundance). Furthermore, the liver FXR-SHP pathway, BAs synthesis and transport underwent adaptive regulation to sustain the BAs homeostasis and hepatic lipid metabolism. CDCA alleviated endoplasmic reticulum (ER) stress induced by palmitic acid via FXR pathway, in HepG2 cells.

SIGNIFICANCE

Lactation BAs metabolism signal in gut-liver axis coordinated the risk of liver damage induced by exacerbated lipolysis in obesogenic pregnancy.

The Inhibitory Effect of Geraniol on CCL4-induced Hepatorenal Toxicity in Pregnant Mice through the PI3K/AKT Signaling Pathway

Background

Hepatotoxicity caused by CCL4 is well known. Geraniol (GNL) has high antioxidant effect that can induces liver regeneration. However, the protective effect of GNL effect on CCL4-induced hepatorenal toxicity in pregnant mice has not yet been studied.

Objective

To investigate whether GNL could protect against oxidative stress induced by CCL4 via the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway, which is regulated by phosphatidylinositol 3 kinase/protein kinase B (PI3K/AKT), and has been found to have protective effects on renal and hepatic tissues.

Materials and Methods

Forty-eight female albino mice weighing 25-30 g were randomly allocated to 4 groups: Group I served as a control; Group II received a toxicity-inducing single dose of 15 μL of CCL4 on the 4th day after mating; Group III received 40 mg/kg GNL + CCL4 (with GNL from the 1st day of assimilation to delivery); and Group IV received GNL alone from the 1st day of assimilation to the end of the delivery period. GNL was evaluated for its protective effects on hepatotoxicity in CCL4-treated pregnant mice. Litter size, weight, survival rate, and resorption were recorded. In addition, H & E staining was done for liver and kidney pathology as well as biochemical markers and oxidative markers malondialdehyde, superoxide dismutase, and catalase were analyzed.

Results

CCL4 significantly reduced survival rate and increased resorption after exposure. Alanine transaminase and aspartate aminotransferase concentrations in the serum, tissue MDA, blood urea nitrogen, and creatinine were increased after CCL4 exposure. GNL improved enzyme and antioxidant levels and prevented CCL4-induced hepatic injury in mice. Caspase-3 cleavage was decreased by GNL, which increased PI3K, phosphorylated AKT, Nrf2, and B-cell lymphoma 2.

Conclusion

GNL demonstrates a protective effect against CCl4-induced hepatorenal toxicity, mediated through the activation of the PI3K/AKT signaling pathway and the upregulation of Nrf2. These findings highlight the potential therapeutic implications of GNL in mitigating oxidative stress and inflammation in liver and kidney tissues.

Non-Viral RNA Delivery During Pregnancy: Opportunities and Challenges

During pregnancy, the risk of maternal and fetal adversities increases due to physiological changes, genetic predispositions, environmental factors, and infections. Unfortunately, treatment options are severely limited because many essential interventions are unsafe, inaccessible, or lacking in sufficient scientific data to support their use. One potential solution to this challenge may lie in emerging RNA therapeutics for gene therapy, protein replacement, maternal vaccination, fetal gene editing, and other prenatal treatment applications. In this review, the current landscape of RNA platforms and non-viral RNA delivery technologies that are under active development for administration during pregnancy is explored. Advancements of pregnancy-specific RNA drugs against SARS-CoV-2, Zika, influenza, preeclampsia, and for in-utero gene editing are discussed. Finally, this study highlights bottlenecks that are impeding translation efforts of RNA therapies, including the lack of accurate cell-based and animal models of human pregnancy and concerns related to toxicity and immunogenicity during pregnancy. Overcoming these challenges will facilitate the rapid development of this new class of pregnancy-safe drugs.

Periportal hepatocyte proliferation at midgestation governs maternal glucose homeostasis in mice

The maternal liver is challenged by metabolic demands throughout pregnancy. However, hepatocyte dynamics and their physiological significance in pregnancy remain unclear. Here, we show in mice that hepatocyte proliferation is spatiotemporally regulated in each liver lobular zone during pregnancy, with transient proliferation of periportal and pericentral hepatocytes during mid and late gestation, respectively. Using adeno-associated virus (AAV)-8-mediated expression of the cell cycle inhibitor p21 in hepatocytes, we show that inhibition of hepatocyte proliferation during mid, but not late, gestation impairs liver growth. Transcriptionally, genes involved in glucose/glycogen metabolism are downregulated in late pregnancy when midgestational hepatocyte proliferation is attenuated. In addition, hepatic glycogen storage is abolished, with concomitant elevated blood glucose concentrations, glucose intolerance, placental glycogen deposition, and fetal overgrowth. Laser capture microdissection and RNA-seq analysis of each liver lobular zone show zone-specific changes in the transcriptome during pregnancy and identify genes that are periportally expressed at midgestation, including the hyaluronan-mediated motility receptor (Hmmr). Knockdown of Hmmr in hepatocytes by AAV8-shHmmr suppresses periportal hepatocyte proliferation at midgestation and induces impaired hepatic glycogen storage, glucose intolerance, placental glycogen deposition and fetal overgrowth. Our results suggest that periportal hepatocyte proliferation during midgestation is critical for maternal glycogen metabolism and fetal size.

Spatial-temporal proliferation of hepatocytes during pregnancy revealed by genetic lineage tracing

The maternal liver undergoes dramatic enlargement to adapt to the increased metabolic demands during pregnancy. However, the cellular sources for liver growth during pregnancy remain largely elusive. Here, we employed a proliferation recording system, ProTracer, to examine the spatial-temporal proliferation of hepatocytes during pregnancy. We discovered that during early to late pregnancy, hepatocyte proliferation initiated from zone 1, to zone 2, and lastly to zone 3, with the majority of new hepatocytes being generated in zone 2. Additionally, using single-cell RNA sequencing, we observed that Ccnd1 was highly enriched in zone 2 hepatocytes. We further applied dual-recombinase-mediated genetic lineage tracing to reveal that Ccnd1+ hepatocytes expanded preferentially during pregnancy. Moreover, we demonstrated that estrogen induces liver enlargement during pregnancy, which was abolished in Ccnd1 knockout mice. Our work revealed a unique spatial-temporal hepatocyte proliferation pattern during pregnancy, with Ccnd1+ hepatocytes in zone 2 serving as the major cellular source for hepatic enlargement.

Impact of high-fat diet and exposure to constant light on reproductive competence of female ICR mice

Obesity and exposure to light at night are prevalent in modern society and associated with changes in physiology and behavior that can affect a female's ability to support offspring growth during pregnancy and lactation. A 2X3 factor study of ICR mice was conducted to determine the effect of diet [control (CON; 10% fat) or high fat (HF; 60% fat)] and exposure to regular 12 h light:dark cycles (LD) or continuous low (L5) or high (L100) lux of light on gestation length, birth litter size, milk composition and litter growth to lactation day 12. HF diet reduced birth litter size, but increased postnatal d 12 litter weight (P<0.05), whereas constant light tended to increase litter weight (P=0.07). Continuous light increased gestation length, altered dam feed intake, increased serum prolactin and increased final dam and mammary gland weight (P<0.05), while decreasing mammary ATP content and milk lactose (P<0.05). Correlation analysis indicated a positive relationship between final litter weight and mammary size, metabolic stores (e.g. maternal fat pad weight), kcal of feed intake, and gestation length (P<0.05). Although CON mice spent more time eating than HF dams, the calorically dense HF diet was related to greater rates of litter growth to peak lactation. Constant light circadian disrupting effects appear to be confounded by a potential long day photoperiod response exemplified by higher circulating levels of prolactin and increased body and mammary weight of females exposed to these conditions. Other model systems may be better to study the interacting effects of obesity and circadian disruption on reproductive competence.

Peroxisome proliferator-activated receptor α agonist induces mouse hepatomegaly through the spatial hepatocyte enlargement and proliferation

Peroxisome proliferator-activated receptor alpha (PPARα) activation-induced hepatomegaly is accompanied by hepatocyte hypertrophy around the central vein (CV) area and hepatocyte proliferation around the portal vein (PV) area. However, the molecular mechanisms underlying this spatial change of hepatocytes remains unclear. In this study, we examined the characteristics and possible reasons for the zonation distinction of hypertrophy and proliferation during PPARα activation-induced mouse liver enlargement. Mice were injected with corn oil or a typical mouse PPARα agonist WY-14643 (100 mg·kg-1·d-1, i.p.) for 1, 2, 3, 5 or 10 days. At each time point, the mice were sacrificed after the final dose, and liver tissues and serum were harvested for analysis. We showed that PPARα activation induced zonal changes in hepatocyte hypertrophy and proliferation in the mice. In order to determine the zonal expression of proteins related to hepatocyte hypertrophy and proliferation in PPARα-induced liver enlargement, we performed digitonin liver perfusion to separately destroy the hepatocytes around the CV or PV areas, and found that PPARα activation-induced increase magnitude of its downstream targets such as cytochrome P450 (CYP) 4 A and acyl-coenzyme A oxidase 1 (ACOX1) levels around the CV area were higher compared with those around the PV area. Upregulation of proliferation-related proteins such as cell nuclear antigen (PCNA) and cyclin A1 (CCNA1) after WY-14643-induced PPARα activation mainly occurred around the PV area. This study reveals that the zonal expression of PPARα targets and proliferation-related proteins is responsible for the spatial change of hepatocyte hypertrophy and proliferation after PPARα activation. These findings provide a new insight into the understanding of PPARα activation-induced liver enlargement and regeneration.

Maternal hepatic adaptations during obese pregnancy encompass lobe-specific mitochondrial alterations and oxidative stress

Maternal obesity (MO) is rising worldwide, affecting half of all gestations, constituting a possible risk-factor for some pregnancy-associated liver diseases (PALD) and hepatic diseases. PALD occur in approximately 3% of pregnancies and are characterized by maternal hepatic oxidative stress (OS) and mitochondrial dysfunction. Maternal hepatic disease increases maternal and fetal morbidity and mortality. Understanding the role of MO on liver function and pathophysiology could be crucial for better understanding the altered pathways leading to PALD and liver disease, possibly paving the way to prevention and adequate management of disease. We investigated specific hepatic metabolic alterations in mitochondria and oxidative stress during MO at late-gestation. Maternal hepatic tissue was collected at 90% gestation in Control and MO ewes (fed 150% of recommended nutrition starting 60 days before conception). Maternal hepatic redox state, mitochondrial respiratory chain (MRC), and OS markers were investigated. MO decreased MRC complex-II activity and its subunits SDHA and SDHB protein expression, increased complex-I and complex-IV activities despite reduced complex-IV subunit mtCO1 protein expression, and increased ATP synthase ATP5A subunit. Hepatic MO-metabolic remodeling was characterized by decreased adenine nucleotide translocator 1 and 2 (ANT-1/2) and voltage-dependent anion channel (VDAC) protein expression and protein kinase A (PKA) activity (P<0.01), and augmented NAD+/NADH ratio due to reduced NADH levels (P<0.01). MO showed an altered redox state with increased OS, increased lipid peroxidation (P<0.01), decreased GSH/GSSG ratio (P=0.005), increased superoxide dismutase (P=0.03) and decreased catalase (P=0.03) antioxidant enzymatic activities, lower catalase, glutathione peroxidase (GPX)-4 and glutathione reductase protein expression (P<0.05), and increased GPX-1 abundance (P=0.03). MO-related hepatic changes were more evident in the right lobe, corroborated by the integrative data analysis. Hepatic tissue from obese pregnant ewes showed alterations in the redox state, consistent with OS and MRC and metabolism remodeling. These are hallmarks of PALD and hepatic disease, supporting MO as a risk-factor and highlighting OS and mitochondrial dysfunction as mechanisms responsible for liver disease predisposition.

Maternal hepatic immunology during pregnancy

The liver plays pivotal roles in immunologic responses, and correct hepatic adaptations in maternal immunology are required during pregnancy. In this review, we focus on anatomical and immunological maternal hepatic adaptations during pregnancy, including our recent reports in this area. Moreover, we summarize maternal pregnancy-associated liver diseases, including hyperemesis gravidarum; intrahepatic cholestasis of pregnancy; preeclampsia, specifically hemolysis, elevated liver enzymes, and low platelet count syndrome; and acute fatty liver of pregnancy. In addition, the latest information about the factors that regulate hepatic immunology during pregnancy are reviewed for the first time, including human chorionic gonadotropin, estrogen, progesterone, growth hormone, insulin like growth factor 1, oxytocin, adrenocorticotropic hormone, adrenal hormone, prolactin, melatonin and prostaglandins. In summary, the latest progress on maternal hepatic anatomy and immunological adaptations, maternal pregnancy-associated diseases and the factors that regulate hepatic immunology during pregnancy are discussed, which may be used to prevent embryo loss and abortion, as well as pregnancy-associated liver diseases.

Expression of IkappaB Family in the Ovine Liver during Early Pregnancy

During normal pregnancy, there is a dynamic regulation of the maternal immune system, including the liver, to accommodate the presence of the allogeneic foetus in the uterus. However, it was unclear that the expression of the IkappaB (IκB) family was regulated in the ovine maternal liver during early pregnancy. In this study, sheep livers were collected at day 16 of the oestrous cycle (NP16), and days 13, 16 and 25 of gestation (DP13, DP16 and DP25), and RT-qPCR, Western blot and immunohistochemistry analysis were used to analyse the expression of the IκB family, including B cell leukemia-3 (BCL-3), IκBα, IκBβ, IκBε, IKKγ, IκBNS and IκBζ. The results revealed that expression of BCL-3, IκBβ, IκBε and IKKγ peaked at DP16, and the expression of IκBα was increased during early pregnancy. In addition, the expression of IκBζ peaked at DP13 and DP16, and IκBNS peaked at DP13. IκBβ and IKKγ proteins were located in the endothelial cells of the proper hepatic arteries and portal veins, and hepatocytes. In conclusion, early pregnancy changed the expression of the IκB family, suggesting that the modulation of the IκB family may be related to the regulation of maternal hepatic functions, which may be favourable for pregnancy establishment in sheep.

Young-Onset Breast Cancer Outcomes by Time Since Recent Childbirth in Utah

IMPORTANCE

Breast cancer diagnosed within 5 to 10 years after childbirth, called postpartum breast cancer (PPBC), is associated with increased risk for metastasis and death. Whether a postpartum diagnosis is an independent risk factor or a surrogate marker of cancer features associated with poor outcomes remains understudied.

OBJECTIVE

To determine whether diagnostic temporal proximity to childbirth is associated with features of breast cancer associated with poor outcomes, including tumor stage, estrogen receptor (ER) status, and risk for distant metastasis and breast cancer-specific mortality, using a population database from the state of Utah.

DESIGN, SETTING, AND PARTICIPANTS

This population-based cohort study using the Utah Population Database (UPDB) included individuals with stage I to III breast cancer diagnosed at age 45 years or younger between 1996 and 2017, followed-up until February 2020. Participant data were analyzed from November 2019 to August 2022.

EXPOSURE

The primary exposures were no prior childbirth or time between most recent childbirth and breast cancer diagnosis. Patients were grouped by diagnoses within less than 5 years, 5 to less than 10 years, or 10 years or more since recent childbirth.

MAIN OUTCOMES AND MEASURES

The 2 primary outcomes were distant metastasis-free survival and breast cancer-specific death. Cox proportional hazard models were used to investigate associations between exposures and outcomes adjusting for diagnosis year, patient age, tumor stage, and estrogen receptor (ER) status.

RESULTS

Of 2970 individuals with breast cancer diagnosed at age 45 years or younger (mean [SD] age, 39.3 [5.0] years; 12 Black individuals [0.4%], 2679 White individuals [90.2%]), breast cancer diagnosis within 5 years of recent childbirth was independently associated with approximately 1.5-fold elevated risk for metastasis (hazard ratio [HR], 1.5; 95% CI, 1.2-2.0) and breast cancer-specific death (HR, 1.5; 95% CI, 1.1-2.1) compared with nulliparous individuals. For cancers classically considered to have tumor features associated with good outcomes (ie, stage I or II and ER-positive), a postpartum diagnosis was a dominant feature associated with increased risk for metastasis and death (eg, for individuals with ER-positive disease diagnosed within <5 years of childbirth: age-adjusted metastasis HR, 1.5; 95% CI, 1.1-2.1; P = .01; age-adjusted death HR, 1.5; 95% CI, 1.0-2.1; P = .04) compared with nulliparous individuals. Furthermore, liver metastases were specifically increased in the group with diagnosis within 5 years postpartum and with positive ER expression (38 of 83 patients [45.8%]) compared with the nulliparous (28 of 77 patients [36.4%]), although the difference was not statistically significant. Overall, these data implicate parity-associated breast and liver biology in the observed poor outcomes of PPBC.

CONCLUSIONS AND RELEVANCE

In this cohort study of individuals with breast cancer diagnosed at age 45 years or younger, a postpartum breast cancer diagnosis was a risk factor associated with poor outcomes. Irrespective of ER status, clinical consideration of time between most recent childbirth and breast cancer diagnosis could increase accuracy of prognosis in patients with young-onset breast cancer.

Changes in Visceral and Ectopic Adipose Tissue Stores Across Pregnancy and Their Relationship to Gestational Weight Gain

BACKGROUND

Excessive gestational weight gain has been associated with increased total body fat (TBF), metabolic syndrome, and abdominal obesity. However, little is known about the relationship of gestational weight gain with changes in metabolically active visceral or ectopic (hepatic and skeletal muscle) lipid stores.

OBJECTIVES

In a prospective study of 50 healthy, pregnant women, we assessed whether changes in weight were associated with changes in total, visceral, and ectopic lipid stores.

METHODS

Participants (ages 19-39) were primarily White (84%). The mean preconception BMI was 25.8 kg/m2 (SD, 4.5 kg/m2; min-max, 17.1-35.9 kg/m2). Measurements were completed at visits 1 and 2 at means of 16 and 34 weeks gestation, respectively, and included TBF using BOD POD; abdominal subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) using MRI; and intrahepatic lipids (IHL), intramyocellular lipids (IMCL), and extramyocellular lipids (EMCL) using magnetic resonance spectroscopy. We used paired t-tests to examine changes in adipose tissue and Pearson's correlation to examine associations of adipose tissue changes and weight changes. We also examined whether changes in adipose tissue stores differed by preconception BMI (normal, overweight, and obese), using 1-way ANOVA.

RESULTS

The TBF (mean change, +3.5 kg; 95% CI: 2.4-4.6 kg), SAT (mean change, +701 cm3; 95% CI: 421-981 cm3), VAT (mean change, +275 cm3; 95% CI: 170-379 cm3), and IHL (percentage water peak; median, +0.15; IQR = -0.01 to 0.32) values increased significantly; the IMCL and EMCL values did not change. Changes varied by BMI strata, with the least increase (or, for SAT, net loss) among women with obesity. Weight change was positively correlated with changes in TBF (r = 0.83; P < 0.001), SAT (r = 0.74; P < 0.001), and VAT (r = 0.63; P < 0.001) but not significantly correlated with changes in ectopic lipids (IHL, IMCL, and EMCL; -0.14 < r < 0.26).

CONCLUSIONS

Preferential deposition of adipose tissue to the viscera in pregnancy, as seen in our sample, could serve an important metabolic function; however, excessive deposition in this region could negatively affect maternal health.