Beyond stillbirth: association of intrahepatic cholestasis of pregnancy severity and adverse outcomes

Preterm birth and stillbirth: total bile acid levels in intrahepatic cholestasis of pregnancy and outcomes of twin pregnancies: a retrospective cohort study from 2014 to 2022

BACKGROUND

Intrahepatic cholestasis of pregnancy (ICP) is a pregnancy-specific liver disorder characterized by maternal pruritus and elevated serum bile acids. Twin pregnancies, as a type of high-risk pregnancy, present additional complexities when complicated by ICP compared to singleton pregnancies. Our study aims to investigate the relationship between bile acid levels in intrahepatic cholestasis of pregnancy and adverse pregnancy outcomes such as preterm birth and stillbirth in twin pregnancies.

METHODS

This retrospective single-center cohort study was conducted at the Second Hospital of Sichuan University from January 2014 to July 2022, focusing on twin pregnancies complicated by ICP. Patients were grouped based on peak levels of total bile acids during pregnancy. Differences among these groups in gestational weeks at delivery, preterm birth, fetal growth restriction, fetal distress, stillbirth, premature rupture of membranes, meconium-stained amniotic fluid, and newborn birth weight were observed as pregnancy outcome indicators.

RESULTS

In 1156 twin pregnancies complicated by ICP, were 430 cases classified as mild, 392 as moderate-low, 292 as moderate-high, and 42 as severe. Regarding pregnancy outcomes, significant differences were observed among the four groups of pregnant women in terms of gestational weeks at delivery (P < 0.001), rate of preterm birth (P < 0.001), newborn birth weight (P < 0.001), incidence of meconium-stained amniotic fluid (P < 0.001), and proportion of low birth weight infants (P < 0.001).

CONCLUSION

The study results indicate that the severity of intrahepatic cholestasis of pregnancy (ICP) is associated with adverse pregnancy outcomes such as preterm birth, newborn birth weight, and meconium-stained amniotic fluid contamination. Additionally, among different bile acid level groups, gestational weeks at delivery showed varying trends in stillbirth occurrence.

Serial Total Bile Acid Measurements in Intrahepatic Cholestasis of Pregnancy

Although peak serum total bile acid (TBA) levels guide management of intrahepatic cholestasis of pregnancy (ICP), whether ICP progresses in severity and when or how to assess bile acid levels serially remains unclear. We conducted a secondary analysis of a single-institution retrospective cohort study to assess bile acid trends across pregnancy among individuals diagnosed with ICP and to evaluate whether there was progression to higher ICP severity. We defined ICP severity as mild (peak TBA less than 40 micromol/L), moderate (peak TBA between 40 and 100 micromol/L), or severe (peak TBA 100 micromol/L or greater). Among the 1,188 patients with ICP in our cohort, 354 (29.8%) had repeat bile acid level measurements. Of those patients, 88 (24.9%) progressed to higher ICP severity that may have resulted in changes to delivery timing. Further studies are needed to determine whether serial assessment of bile acid levels with potential reclassification of ICP severity improves outcomes.

Ultrasonographic assessment of the fetal heart in intrahepatic cholestasis of pregnancy: Pulsed wave Doppler, M-mode, and tissue Doppler imaging prospective study

OBJECTIVES

To investigate the fetal heart using pulsed wave Doppler, M-mode, and tissue Doppler imaging (TDI) in cases of intrahepatic cholestasis of pregnancy (ICP).

METHODS

This prospective study was conducted at a single tertiary center and included 35 patients with ICP and 70 healthy pregnant women at 28-36 weeks of pregnancy. Among the patients with ICP, 26 had serum bile acid (SBA) levels less than 40 μmol/L and nine had SBA levels of 40 μmol/L or greater. Pulsed wave Doppler, M-mode, and TDI evaluations were performed on the patients to assess fetal cardiac function.

RESULTS

The ICP group exhibited significantly higher myocardial performance index (MPI) and isovolumetric relaxation time (IRT), but similar isovolumetric contraction time (ICT). The tricuspid and mitral valve E, A, and E/A ratios were significantly reduced in the ICP group. The TDI parameters showed significantly reduced tricuspid and mitral valve E'/A' ratios in the ICP group compared with the control group (P < 0.001). The E/E' ratio was significantly increased in the ICP group (P < 0.001). According to the M-mode Doppler findings, tricuspid and mitral annular plane systolic excursion values were significantly decreased in the ICP group (P = 0.005 and P = 0.001, respectively). In the subgroup analysis, MPI and IRT were significantly higher in the severe ICP group.

CONCLUSION

ICP might induce changes in the fetal heart during the early systolic and diastolic phases. The detection of these early changes using M-mode and TDI during the antenatal period can provide valuable insights into the condition of the fetus.

Chorionic-based intrahepatic cholestasis in pregnancy on perinatal outcome in twin pregnancies

This study investigates the impact of twin intrahepatic cholestasis in pregnancy (ICP) in different chorionicity scenarios on pregnancy outcome and risk factors. This retrospective study was designed to investigate the association between ICP and pregnancy outcomes and associated risk factors. Logistic regression analysis was used to verify the correlation between ICP and pregnancy outcome and the associated risk factors with the risk of ICP. Pregnant women with ICP had less gestational weight gain (16.19 ± 5.28 vs 17.78 ± 7.19, P = .018), a smaller number of deliveries (16.26% vs 26.40%, P = .016), and less spontaneous pregnancy (50.41% vs 61.73%, P = .019). The mean birth weight of pregnant women without ICP was lower (2328.07 ± 461.82 vs 2404.70 ± 504.58, P = .023), and the prepregnancy hepatitis B virus (HBV) antigen carrying rate was lower (12.20% vs 6.16%, P = .021). Pregnancy weight gain (0.95 (0.92, 0.99) P = .009) and the number of weeks in labor (0.88 (0.81, 0.96) P = .003) were negatively associated with the risk of ICP. Assisted reproductive technology use (1.38 (0.70, 1.79) P = .635) and HBV carrier before pregnancy (2.51 (1.42, 4.48) P = .002) were positively associated with ICP risk. In monochorionic twins, those with ICP were more likely to have abnormal amniotic fluid (15.79% vs 2.16%, P = .012), while those without ICP were less likely to have abnormal amniotic fluid (0.90 (0.83, 0.97) P = .004). In double chorion twins, the incidence of preterm birth was higher in women with ICP (40.00% vs 24.14, P = .002), and the risk of preterm birth was reduced in women without ICP (0.87 (0.79, 0.96) P = .005). In terms of neonatal outcomes, women with ICP were more likely to have a stillbirth (5.26% vs 0.48% P = .037), and stillbirth was less likely to occur without ICP (0.95 (0.92, 0.98) P = .002). Our study illustrates that twin pregnancies with maternal comorbid ICP have lower birth weight, degree of weight gain during pregnancy and prepregnancy HBV carriage is strongly associated with the development of ICP. ICP contributes to adverse perinatal outcomes such as stillbirth, preterm labor, and differentiates between different chorionic twin pregnancy outcomes. The risk of ICP is differently affected by the degree of weight gain during pregnancy, gestational week of delivery, assisted reproductive technology, and prepregnancy HBV carriage.

Simplifying Management of Cholestasis: A Proposal for a Classification System

Given the stillbirth risk associated with intrahepatic cholestasis of pregnancy, management to reduce this adverse outcome has primarily involved planned delivery as early as 36 weeks gestation. While earlier planned delivery has decreased the incidence of stillbirth in this population, recently, there have been multiple published retrospective studies to better correlate the association of adverse outcomes with cholestasis severity. Despite these new data, the uptake of individualized management for cholestasis has been varied from provider to provider. In this opinion, we briefly review the current literature and evidence regarding cholestasis and adverse outcomes and propose a cholestasis classification system with subsequent algorithms for management. KEY POINTS: · Recently, multiple studies have further characterized adverse outcomes with cholestasis.. · Incorporation of severity-associated management into clinical practice is variable.. · A cholestasis classification system will simplify and streamline management..

Adverse Outcomes Associated with Progressive Intrahepatic Cholestasis of Pregnancy

OBJECTIVE

 This study aimed to assess the association between increasing bile acid levels in pregnancies with cholestasis and adverse outcomes.

STUDY DESIGN

 This is a retrospective cohort study of singleton, non-anomalous gestations complicated by cholestasis delivered at a single academic medical center from 2005 to 2019. We compared rates of adverse outcomes in pregnancies complicated by mild cholestasis (initial total bile acid [TBA] <40 μmol/L and peak TBA <40 μmol/L), progressive cholestasis (initial TBA <40 μmol/L and peak TBA ≥40 μmol/L), and severe cholestasis (initial TBA ≥40 μmol/L). Our primary outcome was a composite adverse outcome including spontaneous preterm labor and delivery, umbilical artery pH <7.20, 5-minute Apgar <7, cesarean delivery for nonreassuring fetal heart rate tracing, meconium-stained amniotic fluid, and neonatal intensive care unit (NICU) admission. Analyses were performed using mild cholestasis as the base comparator and a second analysis using severe cholestasis as the base comparator.

RESULTS

 Of the 1,182 pregnancies complicated by cholestasis, 732 (61.9%) had mild cholestasis, 78 (6.6%) had progressive cholestasis, and 372 (31.5%) had severe cholestasis. After adjusting for confounders including gestational age at diagnosis and using mild cholestasis as the base comparator, both progressive and severe cholestasis were associated with the composite adverse outcome (progressive intrahepatic cholestasis of pregnancy [ICP] OR 1.70; 95% CI 1.04-2.78 and severe ICP OR 1.60; 95% CI 1.24-2.06). When using progressive cholestasis as the base comparator, there were no statistically significant differences in the primary or secondary outcomes between progressive cholestasis and severe cholestasis.

CONCLUSION

 This study highlights the significance of monitoring peak bile acid levels and that some cases of cholestasis may progress in pregnancy and the adverse associations are better reflected by the peak TBA level and not the cholestasis severity at initial diagnosis.

KEY POINTS

· Outcomes with worsening cholestasis severity (progressive) are unknown.. · Retrospective study comparing mild to progressive to severe cholestasis.. · Progressive cholestasis outcomes are more similar to severe cholestasis.. · Clinical utility of trending bile acids warrants further study..

Impacts of prenatal environmental exposures on fetal-placental-maternal bile acid homeostasis and long-term health in offspring

During pregnancy, the maternal body undergoes a series of adaptative physiological changes, leading to a slight increase in serum bile acid (BA) levels. Although the fetal liver can synthesize BAs since the first trimester through the alternative pathway, the BA metabolic system is immature in the fetus. Compared to adults, the fetus has a distinct composition of BA pool and limited expression of BA synthesis enzymes and transporters. Besides, the "enterohepatic circulation" of BAs is absent in fetus. Thus, fetal BAs need to be transported to the mother through the placenta for further metabolism and excretion, and maternal BAs can also be transported to the fetus. That is what we call the "fetal-placental-maternal BA circulation". Various BA transporters and nuclear receptors are essential for maintaining the balance of this BA circulation to ensure normal fetal development. However, prenatal adverse environments can alter fetal BA metabolism, resulting in intrauterine developmental abnormalities and susceptibility to a variety of adult chronic diseases. This review summarizes the current understanding of the fetal-placental-maternal BA circulation and discusses the effects of prenatal adverse environments on this particular BA circulation, aiming to provide a theoretical basis for exploring early prevention and treatment strategies for BA metabolism-associated adverse pregnancy outcomes and long-term impairments.

Proteinuria is a clinical characteristic of intrahepatic cholestasis of pregnancy but it is not a marker of severity: A retrospective cohort study

OBJECTIVES

To determine the prevalence of proteinuria in patients diagnosed with intrahepatic cholestasis of pregnancy (IHCP), and the association between the presence of proteinuria and adverse pregnancy outcomes.

METHODS

This was a retrospective cohort study. The study included all pregnant patients between July 2014 and January 2022, at gestational age > 24weeks who had been diagnosed with IHCP and had completed a 24-hour protein collection. High order multifetal gestations were excluded. Patients were divided into 3 groups:1. IHCP without proteinuria (Non-proteinuric group);2. IHCP with proteinuria and normal blood pressure (Isolated proteinuria group), and 3. IHCP with proteinuria and elevated blood pressure (IHCP with preeclampsia (PET)). Primary outcome was defined as a composite maternal-fetal outcome including: preterm labor <34 weeks, arterial cord blood ph<7.1, rate of Cesarean delivery due to non-reassuring fetal monitoring. Parametric and non-parametric statistical methods were used for analysis.

RESULTS

A total of 272 met all inclusion criteria and were included, 94 patients (34.5%) had proteinuria; of them, 67 (24.6%) had isolated proteinuria and 27 (9.9%) had PET. Demographic parameters were comparable among the groups. Patients with PET had higher rates of in-vitro fertilization (IVF) treatments, twin gestation and elevated serum creatinine and urea levels. The rate of composite adverse pregnancy outcome was higher in patients with PET compared with patients with and without proteinuria (14/27 (51.9%) vs. 18/67 (26.9%) vs. 49/178 (27.5%), respectively, p = 0.03).

CONCLUSIONS

Approximately 35% of patients with IHCP have proteinuria. The presence of PET, rather than isolated proteinuria, is associated with adverse pregnancy outcome.

The severity of intrahepatic cholestasis during pregnancy increases risks of adverse outcomes beyond stillbirth: evidence from 15,826 patients

BACKGROUND

What kinds of fetal adverse outcomes beyond stillbirth directly correlate to the severity of intrahepatic cholestasis during pregnancy (ICP) remained tangled. Herein, we conducted a retrospective cohort study and a dose-response meta-analysis to speculate the association between the severity of ICP and its adverse outcomes.

METHODS

We retrospectively collected a cohort of ICP patients from electronic records from Guangzhou Women and Children's Medical Center between Jan 1st, 2018, and Dec 31st, 2022. Also, we searched PubMed, Cochrane, Embase, Scopus, and Web of Science to extract prior studies for meta-analysis. The Kruskal-Wallis test, a one-way or two-way variants analysis (ANOVA), and multi-variant regression are utilized for cohort study. One stage model, restricted cubic spline analysis, and fixed-effect model are applied for dose-response meta-analysis. The data analysis was performed using the R programme.

RESULTS

Our cohort included 1,289 pregnant individuals, including 385 mild ICP cases, 601 low moderate ICP cases, 282 high moderate ICP cases, and 21 severe ICP cases. The high moderate bile acid levels were correlated to preterm birth [RR = 2.14, 95%CI 1.27 to 3.62), P < 0.01], and preterm premature rupture of membranes [RR = 0.34, 95%CI 0.19 to 0.62), P < 0.01]. We added our cases to cases reported by other studies included in the meta-analysis. There were 15,826 patients included in dose-response meta-analysis. The severity of ICP was associated with increased risks of stillbirth, spontaneous preterm birth, iatrogenic preterm birth, preterm birth, admission to neonatal intensive care unit, and meconium-stained fluid (P < 0.05).

CONCLUSIONS

Our study shows the correlation between the severity of ICP and the ascending risks of stillbirth, preterm birth, and meconium-stained fluid, providing new threshold TBA levels.

PROSPERO REGISTRATION NUMBER

CRD42023472634.

Associations of clinical subtypes and bile acid levels of intrahepatic cholestasis of pregnancy with pregnancy outcomes

Intrahepatic cholestasis of pregnancy (ICP) can lead to many adverse pregnancy outcomes, and the influencing factors remain unclear at present. This study retrospectively analyzed clinical data from 1815 pregnant women with ICP and evaluated the relationship between ICP subtypes, gestational age at onset, and pregnancy outcomes. The results of this study show that during pregnancy, the levels of biochemical indicators (TBA, DBIL and ALT) in the serum of pregnant women initially diagnosed with subtypes of ICP were noted to constantly change, and the subtype of ICP and its severity also changed. The incidence of adverse pregnancy outcomes [meconium-stained amniotic fluid (MSAF), NICU transfer, Apgar score ≤ 7 at 1 min, and preterm birth] in patients with ICP1 (icteric type) was significantly higher than for patients with ICP2, ICP3 or ICP4. The preterm birth rate of early-onset ICP was higher than that of late-onset ICP in ICP1 and ICP3 subtypes. In conclusion, the outcome of pregnancy in women with ICP is closely related to the serum TBA level and ICP subtype, which should be recognized in the clinic.

Role of the microbiota-gut-heart axis between bile acids and cardiovascular disease

Bile acid (BA) receptors (e.g., farnesoid X-activated receptor, muscarinic receptor) are expressed in cardiomyocytes, endothelial cells, and vascular smooth muscle cells, indicating the relevance of BAs to cardiovascular disease (CVD). Hydrophobic BAs are cardiotoxic, while hydrophilic BAs are cardioprotective. For example, fetal cardiac insufficiency in maternal intrahepatic cholestasis during pregnancy, and the degree of fetal cardiac abnormality, is closely related to the level of hydrophobic BAs in maternal blood and infant blood. However, ursodeoxycholic acid (the most hydrophilic BA) can reverse/prevent these detrimental effects of increased levels of hydrophobic BAs on the heart. The gut microbiota (GM) and GM metabolites (especially secondary BAs) have crucial roles in hypertension, atherosclerosis, unstable angina, and heart failure. Herein, we describe the relationship between CVD and the GM at the BA level. We combine the concept of the "microbiota-gut-heart axis" (MGHA) and postulate the role and mechanism of BAs in CVD development. In addition, the strategies for treating CVD with BAs under the MGHA are proposed.

Gestational diabetes mellitus aggravates adverse perinatal outcomes in women with intrahepatic cholestasis of pregnancy

PURPOSE

To evaluate the effect of intrahepatic cholestasis of pregnancy (ICP) with gestational diabetes mellitus (GDM) on perinatal outcomes and establish a prediction model of adverse perinatal outcomes in women with ICP.

METHODS

This multicenter retrospective cohort study included the clinical data of 2,178 pregnant women with ICP, including 1,788 women with ICP and 390 co-occurrence ICP and GDM. The data of all subjects were collected from hospital electronic medical records. Univariate and multivariate logistic regression analysis were used to compare the incidence of perinatal outcomes between ICP with GDM group and ICP alone group.

RESULTS

Baseline characteristics of the population revealed that maternal age (p < 0.001), pregestational weight (p = 0.01), pre-pregnancy BMI (p < 0.001), gestational weight gain (p < 0.001), assisted reproductive technology (ART) (p < 0.001), and total bile acid concentration (p = 0.024) may be risk factors for ICP with GDM. Furthermore, ICP with GDM demonstrated a higher association with both polyhydramnios (OR 2.66) and preterm labor (OR 1.67) compared to ICP alone. Further subgroup analysis based on the severity of ICP showed that elevated total bile acid concentrations were closely associated with an increased risk of preterm labour, meconium-stained amniotic fluid, and low birth weight in both ICP alone and ICP with GDM groups. ICP with GDM further worsened these outcomes, especially in women with severe ICP. The nomogram prediction model effectively predicted the occurrence of preterm labour in the ICP population.

CONCLUSIONS

ICP with GDM may result in more adverse pregnancy outcomes, which are associated with bile acid concentrations.

Risk of stillbirth in United States patients with diagnosed intrahepatic cholestasis of pregnancy

BACKGROUND

Intrahepatic cholestasis of pregnancy is associated with a 4- to 10-fold increase in the risk of stillbirth in the absence of intervention, leading to recommendations for antenatal assessment, ursodiol use, and often preterm or early term delivery.

OBJECTIVE

This study aimed to determine whether current management strategies for intrahepatic cholestasis of pregnancy mitigate the elevated risk of stillbirth at a population level.

STUDY DESIGN

This was a retrospective cohort study using the 2015-2020 National Readmissions Database, an administrative database developed by the United States Agency for Healthcare Research and Quality. Our study identified delivery hospitalizations, gestational age at delivery, occurrence of intrahepatic cholestasis of pregnancy and stillbirth, and comorbid conditions using the International Classification of Diseases diagnosis and procedure codes. Moreover, this study compared the timing of delivery and stillbirth rates of pregnant patients with intrahepatic cholestasis of pregnancy vs those without intrahepatic cholestasis of pregnancy at the time of delivery hospitalization.

RESULTS

This study identified a cohort of 9,987,705 delivery hospitalizations in the National Readmissions Database, corresponding to a weighted national estimate of 18,609,207 births. Of these births, 152,040 (0.8%) were noted to have an intrahepatic cholestasis of pregnancy diagnosis. Patients with an intrahepatic cholestasis of pregnancy diagnosis were older, with small differences in comorbidities, such as a higher rate of gestational diabetes mellitus, than patients without an intrahepatic cholestasis of pregnancy diagnosis at delivery hospitalization. The overall rates of stillbirth were lower among those with intrahepatic cholestasis of pregnancy than among those without intrahepatic cholestasis of pregnancy (252 vs 386 per 100,000 deliveries; risk difference, 133 fewer per 100,000 deliveries; 95% confidence interval, 98-170), a finding that persisted after adjustment for insurance status, socioeconomic factors, and comorbid conditions (risk difference, 160 fewer stillbirths per 100,000 deliveries; 95% confidence interval, 127-194). Furthermore, although patients with intrahepatic cholestasis of pregnancy were more likely to deliver before term than those without intrahepatic cholestasis of pregnancy (30.1% vs 9.3%; P<.001), increased rates of stillbirth were not noted at any point after stratification of the cohort by gestational age at delivery.

CONCLUSION

Patients with intrahepatic cholestasis of pregnancy diagnosis codes delivered earlier than those without intrahepatic cholestasis of pregnancy diagnosis codes, but the percentage of births affected by stillbirth was lower, even when stratifying for gestational age at birth. These results may provide reassurance to patients receiving an intrahepatic cholestasis of pregnancy diagnosis that current management does mitigate stillbirth risk in intrahepatic cholestasis of pregnancy.

Severe cholestasis-associated coagulopathy diagnosed by routine screening: a case report

Recent case reports suggest an association between severe intrahepatic cholestasis of pregnancy and fat-soluble vitamin deficiencies, including vitamin K deficiency. Screening for coagulopathy and fat-soluble vitamin deficiency has been proposed as a possible strategy to identify pregnancies at additional risk of adverse outcomes and allow for earlier risk-reducing iatrogenic preterm delivery. This report highlights a case of routine screening that resulted in the detection of subclinical coagulopathy that allowed for earlier intervention and delivery of a healthy neonate at 34 weeks of gestation. Further prospective studies are needed to determine the clinical use of routine screening in detecting coagulopathy and fat-soluble vitamin deficiency in cases of severe cholestasis.

Cholic acid exposure during late pregnancy causes placental dysfunction and fetal growth restriction by reactive oxygen species-mediated activation of placental GCN2/eIF2α pathway

Epidemiological studies suggest that fetal growth restriction (FGR) caused by gestational cholestasis is associated with elevated serum cholic acid (CA). Here, we explore the mechanism by which CA induces FGR. Pregnant mice except controls were orally administered with CA daily from gestational day 13 (GD13) to GD17. Results found that CA exposure decreased fetal weight and crown-rump length, and increased the incidence of FGR in a dose-dependent manner. Furthermore, CA caused placental glucocorticoid (GC) barrier dysfunction via down-regulating the protein but not the mRNA level of placental 11β-Hydroxysteroid dehydrogenase-2 (11β-HSD2). Additionally, CA activated placental GCN2/eIF2α pathway. GCN2iB, an inhibitor of GCN2, significantly inhibited CA-induced down-regulation of 11β-HSD2 protein. We further found that CA caused excessive reactive oxygen species (ROS) production and oxidative stress in mouse placentas and human trophoblasts. NAC significantly rescued CA-induced placental barrier dysfunction by inhibiting activation of GCN2/eIF2α pathway and subsequent down-regulation of 11β-HSD2 protein in placental trophoblasts. Importantly, NAC rescued CA-induced FGR in mice. Overall, our results suggest that CA exposure during late pregnancy induces placental GC barrier dysfunction and subsequent FGR may be via ROS-mediated placental GCN2/eIF2α activation. This study provides valuable insight for understanding the mechanism of cholestasis-induced placental dysfunction and subsequent FGR.

Imaging of benign gallbladder and biliary pathologies in pregnancy

The rising incidence combined with pregnancy-related physiological changes make gallbladder and biliary pathology high on the differential for pregnant patients presenting with right upper abdominal pain. Imaging plays a crucial role in determining surgical versus non-surgical management in pregnant patients with biliary or gallbladder pathology. Ultrasound (first-line) and magnetic resonance with magnetic resonance cholangiopancreatography (second-line) are the imaging techniques of choice in pregnant patients with suspected biliary pathology due to their lack of ionizing radiation. MRI/MRCP offers an excellent non-invasive imaging option, providing detailed anatomical detail without known harmful fetal side effects. This article reviews physiological changes in pregnancy that lead to gallstone and biliary pathology, key imaging findings on US and MRI/MRCP, and management pathways.

Bile Acids in Intrahepatic Cholestasis of Pregnancy

Intrahepatic cholestasis of pregnancy (ICP) is the most common, reversible, and closely related to pregnancy condition characterized by elevated levels of bile acids (BAs) in blood serum and an increased risk of adverse perinatal outcomes. Due to the complex interactions between the mother and the fetus in metabolism and transplacental BAs transport, ICP is classified as a fetal-maternal disease. The disease is usually mild in pregnant women, but it can be fatal to the fetus, leading to numerous complications, including intrauterine death. The pathophysiology of the disease is based on inflammatory mechanisms caused by elevated BA levels. Although ICP cannot be completely prevented, its early diagnosis and prompt management significantly reduce the risk of fetal complications, the most serious of which is unexpected intrauterine death. It is worth emphasizing that all diagnostics and management of ICP during pregnancy are based on BA levels. Therefore, it is important to standardize the criteria for diagnosis, as well as recommendations for management depending on the level of BAs, which undoubtedly determines the impact on the fetus. The purpose of this review is to present the potential and importance of BAs in the detection and rules of medical procedure in ICP.