Obstetric Outcomes in Women with Nonalcoholic Fatty Liver Disease

Metabolic-associated fatty liver disease and pregnancy complications: new challenges and clinical perspectives

The term metabolic-associated fatty liver disease (MAFLD), with a global prevalence estimated at 38.77%, has gradually replaced the traditional concept of non-alcoholic fatty liver disease (NAFLD). Compared to the general population, the incidence of MAFLD is notably higher among pregnant women, posing potential risks to both maternal and neonatal health. This review summarizes the latest research on MAFLD, focusing on its association with pregnancy complications. Additionally, it provides a comparative analysis with previous studies on NAFLD, presenting a comprehensive perspective for clinical management. Findings suggest that pregnant women with MAFLD face a higher risk of gestational hypertension and cesarean delivery compared to those with NAFLD, while the risk for gestational diabetes mellitus remains similar between the two conditions. Additionally, MAFLD is associated with an increased likelihood of delivering large-for-gestational-age infants and heightened risks of preterm birth and low birth weight. Current treatment strategies for MAFLD focus on lifestyle modifications, such as dietary adjustments and increased physical activity. However, there is an urgent need for the development of safe and effective pharmacological treatments, particularly tailored toward pregnant women. Future research should delve deeper into the causal relationships between MAFLD and pregnancy complications and explore optimal therapeutic approaches to improve outcomes for mothers and their infants.

Obesogenic Diet in Mice Leads to Inflammation and Oxidative Stress in the Mother in Association with Sex-Specific Changes in Fetal Development, Inflammatory Markers and Placental Transcriptome

BACKGROUND

Obesity during pregnancy is related to adverse maternal and neonatal outcomes. Factors involved in these outcomes may include increased maternal insulin resistance, inflammation, oxidative stress, and nutrient mishandling. The placenta is the primary determinant of fetal outcomes, and its function can be impacted by maternal obesity. The aim of this study on mice was to determine the effect of obesity on maternal lipid handling, inflammatory and redox state, and placental oxidative stress, inflammatory signaling, and gene expression relative to female and male fetal growth.

METHODS

Female mice were fed control or obesogenic high-fat/high-sugar diet (HFHS) from 9 weeks prior to, and during, pregnancy. On day 18.5 of pregnancy, maternal plasma, and liver, placenta, and fetal serum were collected to examine the immune and redox states. The placental labyrinth zone (Lz) was dissected for RNA-sequencing analysis of gene expression changes.

RESULTS

the HFHS diet induced, in the dams, hepatic steatosis, oxidative stress (reduced catalase, elevated protein oxidation) and the activation of pro-inflammatory pathways (p38-MAPK), along with imbalanced circulating cytokine concentrations (increased IL-6 and decreased IL-5 and IL-17A). HFHS fetuses were asymmetrically growth-restricted, showing sex-specific changes in circulating cytokines (GM-CSF, TNF-α, IL-6 and IFN-γ). The morphology of the placenta Lz was modified by an HFHS diet, in association with sex-specific alterations in the expression of genes and proteins implicated in oxidative stress, inflammation, and stress signaling. Placental gene expression changes were comparable to that seen in models of intrauterine inflammation and were related to a transcriptional network involving transcription factors, LYL1 and PLAG1.

CONCLUSION

This study shows that fetal growth restriction with maternal obesity is related to elevated oxidative stress, inflammatory pathways, and sex-specific placental changes. Our data are important, given the marked consequences and the rising rates of obesity worldwide.

Nonalcoholic Fatty Liver Disease and Adverse Pregnancy Outcomes in Women With Normal Prepregnant Weight

CONTEXT

Existing studies focusing on the effects of nonalcoholic fatty liver disease (NAFLD) combined with normal prepregnant weight on pregnancy outcomes are limited.

OBJECTIVE

This study aimed to explore the relationship between maternal NAFLD and adverse pregnancy outcomes in different body mass index (BMI) groups.

METHODS

Using an antenatal care and delivery database, we retrospectively analyzed women who delivered in Minhang Hospital affiliated to Fudan University, Shanghai, China from January 1, 2013, to June 30, 2020. NAFLD was confirmed by ultrasound in early pregnancy. A logistic regression model with adjustment for confounders was used to examine potential associations between NAFLD and pregnancy outcomes.

RESULTS

A total of 14 708 pregnant women (mean prepregnant BMI 21.0 [SD, 2.8] kg/m2) were included in our final study, of whom 554 (3.8%) had NAFLD. After fully adjusting for potential confounders, NAFLD significantly increased the risk of gestational diabetes mellitus (adjusted odds ratio 2.477; 95% CI, 1.885-3.254), gestational hypertension (3.054; 2.191-4.257), preeclampsia/eclampsia (3.994; 2.591-6.005), cesarean section (1.569; 1.315-1.872), preterm births (1.831; 1.229-2.727), and macrosomia (1.691; 1.300-2.198). It is notable that 83.9% (12 338) of women were of normal weight at the start of pregnancy (prepregnant 18.5 ≤ BMI < 24 kg/m2), and they still had higher odds of adverse pregnancy outcomes.

CONCLUSION

Women with NAFLD and a normal weight have a higher risk for adverse pregnancy outcomes. Pregnant women with NAFLD, regardless of obesity status, should be offered a more qualified surveillance to optimize pregnancy outcomes.

Obesogenic diet in mice compromises maternal metabolic physiology and lactation ability leading to reductions in neonatal viability

AIMS

Diets containing high-fat and high sugar (HFHS) lead to overweight/obesity. Overweight/obesity increases the risk of infertility, and of the pregnant mother and her child for developing metabolic conditions. Overweight/obesity has been recreated in mice, but most studies focus on the effects of chronic, long-term HFHS diet exposure. Here, we exposed mice to HFHS from 3 weeks prior to pregnancy with the aim of determining impacts on fertility, and gestational and neonatal outcomes.

METHODS

Time-domain NMR scanning was used to assess adiposity, glucose, and insulin tolerance tests were employed to examine metabolic physiology, and morphological and proteomic analyses conducted to assess structure and nutrient levels of maternal organs and placenta.

RESULTS

Fertility measures of HFHS dams were largely the same as controls. HFHS dams had increased adiposity pre-pregnancy, however, exhibited exacerbated lipolysis/hyper-mobilization of adipose stores in late pregnancy. While there were no differences in glucose or insulin tolerance, HFHS dams were hyperglycemic and hyperinsulinemic in pregnancy. HFHS dams had fatty livers and altered pancreatic islet morphology. Although fetuses were hyperglycemic and hyperinsulinemic, there was no change in fetal growth in HFHS dams. There were also reductions in placenta formation. Moreover, there was increased offspring loss during lactation, which was related to aberrant mammary gland development and milk protein composition in HFHS dams.

CONCLUSIONS

These findings are relevant given current dietary habits and the development of maternal and offspring alterations in the absence of an increase in maternal weight and adiposity during pregnancy, which are the current clinical markers to determine risk across gestation.

Maternal liver dysfunction in early pregnancy predisposes to gestational diabetes mellitus independent of preconception overweight: A prospective cohort study

OBJECTIVE

To evaluate whether the associations of maternal liver dysfunction and liver function biomarkers (LFBs) with gestational diabetes mellitus (GDM) are independent of overweight.

DESIGN

Prospective cohort study.

METHODS

A sub-cohort of pregnant women with seven LFBs examined at 9-13 weeks of gestation and with complete GDM evaluation at mid-gestation were extracted from the prospective Shanghai Preconception Cohort Study. Associations of liver dysfunction, defined as having any elevated LFB levels, and individual LFB levels with GDM incidence were assessed by adjusting body mass index and other covariates in the multivariable logistic regression model. Odds ratios (ORs) and 95% CI were reported.

MAIN OUTCOME MEASURES

Incident GDM.

RESULTS

Among 6211 pregnant women, 975 (15.7%) developed GDM. Liver dysfunction was associated with increased odds of GDM (OR 1.63; 95% CI 1.38-1.92). This association persisted after adjustment for BMI (adjusted OR [aOR] 1.37; 95% CI 1.15-1.63). Higher γ-glutamyl transferase, alanine aminotransferase, alkaline phosphatase, and albumin levels were also linked with GDM (aOR per 1 SD: 1.15, 95% CI 1.08-1.23; 1.10, 1.03-1.17; 1.21, 1.13-1.29 and 1.19, 1.11-1.27, respectively). Similar magnitudes of associations were observed between normal weight and overweight pregnant women.

CONCLUSION

Maternal liver dysfunction in early pregnancy predisposes women to subsequent GDM, and this association is independent of being overweight preconception. Our findings of an increased risk even in normal-weight pregnant women adds new mechanistic insights about the pathophysiological role of liver function in GDM aetiology.

Implications of abnormal liver function in pregnancy and non-alcoholic fatty liver disease

Elevated liver enzyme levels can sometimes be encountered in asymptomatic pregnant women. Similar to non-pregnant subjects, women with elevated gamma glutamyltransferase or alanine aminotransferase in early pregnancy have increased risk of subsequent complications, especially gestational diabetes mellitus. In non-pregnant subjects, the commonest cause of abnormal liver function currently is non-alcoholic fatty liver disease. Risk factors include obesity, diabetes, and the metabolic syndrome. It can progress to hepatocellular carcinoma through the development of steatohepatitis, and has become the leading cause for liver transplantation in women. Found in as many as 16-18% of pregnant women, it is associated with an increased risk of pregnancy complications and abnormal foetal growth, which predisposes the offspring to the same problem subsequently. This condition probably explains the majority of the cases of "idiopathic" abnormal liver function in pregnancy, and should be looked out for in high-risk women owing to its implications on their long-term health outcome.