Profiles of bile acids and progesterone metabolites in the urine and serum of women with intrahepatic cholestasis of pregnancy

Molecular pathogenesis of intrahepatic cholestasis of pregnancy

Intrahepatic cholestasis of pregnancy (ICP) occurs mainly in the third trimester and is characterised by pruritus and elevated serum bile acid levels. ICP is associated with an increased perinatal risk and higher rates of foetal morbidity and mortality. Although the pathogenesis of this disease is unknown, a genetic hypersensitivity to female hormones (oestrogen and/or progesterone) or their metabolites is thought to impair bile secretory function. Recent data suggest that mutations or polymorphisms of genes expressing hepatobiliary transport proteins or their nuclear regulators may contribute to the development and/or severity of ICP. Unidentified environmental factors may also influence pathogenesis of the disease. This review summarises current knowledge on the potential mechanisms involved in ICP at the molecular level.

Mechanisms of cholestasis

This article gives an overview of the molecular and cellular mechanisms of cholestasis. Topics reviewed include the pathomechanisms of hereditary cholestasis syndromes, such as progressive familial intrahepatic cholestasis, and hepatocellular transporter defects encountered in various acquired cholestatic disorders, such as intrahepatic cholestasis of pregnancy, drug-induced cholestasis, inflammatory cholestasis, primary sclerosing cholangitis, and primary biliary cirrhosis. In addition, current concepts regarding adaptive hepatocellular mechanisms counteracting cholestatic liver damage are discussed.

Intrahepatic cholestasis of pregnancy

Intrahepatic cholestasis of pregnancy (ICP) is a cholestatic disorder characterized by (i) pruritus with onset in the second or third trimester of pregnancy, (ii) elevated serum aminotransferases and bile acid levels, and (iii) spontaneous relief of signs and symptoms within two to three weeks after delivery. ICP is observed in 0.4–1% of pregnancies in most areas of Central and Western Europe and North America, while in Chile and Bolivia as well as Scandinavia and the Baltic states roughly 5–15% and 1–2%, respectively, of pregnancies are associated with ICP. Genetic and hormonal factors, but also environmental factors may contribute to the pathogenesis of ICP. Intrahepatic cholestasis of pregnancy increases the risk of preterm delivery (19–60%), meconium staining of amniotic fluid (27%), fetal bradycardia (14%), fetal distress (22–41%), and fetal loss (0.4–4.1%), particularly when associated with fasting serum bile acid levels > 40 μmol/L. The hydrophilic bile acid ursodeoxycholic acid (10–20 mg/kg/d) is today regarded as the first line treatment for intrahepatic cholestasis of pregnancy. Delivery has been recommended in the 38^th week when lung maturity has been established.

LC/ESI-tandem mass spectrometric determination of bile acid 3-sulfates in human urine

We developed a highly sensitive and quantitative method to detect bile acid 3-sulfates in human urine employing liquid chromatography/electrospray ionization-tandem mass spectrometry. This method allows simultaneous analysis of bile acid 3-sulfates, including nonamidated, glycine-, and taurine-conjugated bile acids, cholic acid (CA), chenodeoxycholic acid (CDCA), deoxycholic acid (DCA), ursodeoxycholic acid (UDCA), and lithocholic acid (LCA), using selected reaction monitoring (SRM) analysis. The method was applied to analyze bile acid 3-sulfates in human urine from healthy volunteers. The results indicated an unknown compound with the nonamidated common bile acid 3-sulfates on the chromatogram obtained by the selected reaction monitoring analysis. By comparison of the retention behavior and MS/MS spectrum of the unknown peak with the authentic specimen, the unknown compound was identified as 3beta,12alpha-dihydroxy-5beta-cholanoic acid 3-sulfate.

Cholestasis in pregnancy associated with ciclosporin therapy in renal transplant recipients

Obstetric cholestasis (OC) presents with pruritus in the second half of pregnancy and is associated with increased risk of foetal distress, intra-uterine death and premature delivery. From a tertiary referral, renal-obstetric clinic, we report the occurrence of OC in 5/23 pregnancies of women with renal transplants maintained on ciclosporin treatment (European incidence 0.1-1.5% of pregnancies). All required premature delivery for foetal reasons at 33-37/40 (median 34/40). Ciclosporin, at therapeutic concentrations, inhibits bile salt excretion pump (BSEP) function in rats and humans. We propose that OC developed in our patients because the mild inhibition of the canalicular pumps by ciclosporin was only revealed in pregnancy when increases in progesterone metabolites overwhelmed pump function. We suggest that all pregnant women receiving ciclosporin should be closely monitored from the second trimester for the development of OC. If detected, enhanced foetal and maternal monitoring to optimize time of delivery and pregnancy outcome is required.

Altered pharmacokinetics and hepatic uptake of TBuMA in ethynylestradiol-induced cholestasis

The objective of this study was to examine the pharmacokinetics of organic cations in intrahepatic cholestatic rats. A pretreatment with 17alpha-ethynylestradiol was used to induce intrahepatic cholestasis, and tributylmethylammonium (TBuMA) was used as a representative model organic cation. When [3H]TBuMA was intravenously administered1 the AUC value for TBuMA was significantly increased by 79% in cholestasis, and its total systemic clearance was consequently decreased by 46%. In addition, the in vivo hepatic uptake clearance of TBuMA from the plasma to the liver was decreased by 50% in cholestasis. The concentration of bile salts in plasma was increased by 2.1 fold in cholestatic rats. Since TBuMA forms ion-pair complexes with anionic components such as bile salts, the decreased hepatic uptake of TBuMA in cholestasis may be due to a change in endogenous components, e.g., bile salts in the plasma. In isolated normal hepatocytes, the uptake clearance for TBuMA in the presence of cholestatic plasma was decreased by 20% compared with normal plasma. Therefore, we conclude that the inhibition of the hepatic uptake process by the cholestasis may be in part due to the increased formation of ion-pair complexes of TBuMA with bile salts in the plasma.

Potential role of trans-inhibition of the bile salt export pump by progesterone metabolites in the etiopathogenesis of intrahepatic cholestasis of pregnancy

BACKGROUND/AIMS

Progesterone metabolites such as 5alpha-pregnan-3alpha-ol-20-one (PM4) are elevated in serum of women with intrahepatic cholestasis of pregnancy (ICP).

METHODS/RESULTS

When assayed in isolated perfused rat liver, PM4 did not induce cholestasis, whereas sulfated PM4 (PM4-S), which unlike PM4 is secreted into bile, reduced bile flow and bile acid (BA) output. Whether PM4-S inhibited the bile salt export pump (BSEP) was investigated. Radiolabeled methylesters (ME) of cholic acid and chenodeoxycholic acid were taken up by Xenopus laevis oocytes co-expressing rat BSEP and human carboxylesterase-1 (CES1), efficiently hydrolyzed to free BAs by CES1 and subsequently exported by BSEP. Rifampicin or cyclosporin A in the extracellular medium had no effect on BA efflux. In contrast, estradiol 17beta-D-glucuronide and several progesterone metabolites, including PM4-S, induced a marked non-competitive trans-inhibition of BSEP-mediated BA efflux (Ki=20-60 microM). Mitochondrial activity was markedly impaired in oocytes incubated with BA-MEs, but not with free BAs. Co-expression of CES1 and BSEP partly protected oocytes from this toxic effect. Trans-inhibition of BSEP abolished this protection.

CONCLUSIONS

Several estrogens and progesterone metabolites are able to induce trans-inhibition of BSEP and the subsequent toxicity induced by the accumulation of BAs, which may play a role in the etiopathogenesis of ICP.

Fifty years with bile acids and steroids in health and disease

Cholesterol and its metabolites, e.g., steroid hormones and bile acids, constitute a class of compounds of great biological importance. Their chemistry, biochemistry, and regulation in the body have been intensely studied for more than two centuries. The author has studied aspects of the biochemistry and clinical chemistry of steroids and bile acids for more than 50 years, and this paper, which is an extended version of the Schroepfer Medal Award lecture, reviews and discusses part of this work. Development and application of analytical methods based on chromatography and mass spectrometry (MS) have been a central part of many projects, aiming at detailed characterization and quantification of metabolic profiles of steroids and bile acids under different conditions. In present terminology, much of the work may be termed steroidomics and cholanoidomics. Topics discussed are bile acids in human bile and feces, bile acid production, bacterial dehydroxylation of bile acids and steroids during the enterohepatic circulation, profiles of steroid sulfates in plasma of humans and other primates, development of neutral and ion-exchanging lipophilic derivatives of Sephadex for sample preparation and group separation of steroid and bile acid conjugates, profiles of steroids and bile acids in human urine under different conditions, hydroxylation of bile acids in liver disease, effects of alcohol-induced redox changes on steroid synthesis and metabolism, alcohol-induced changes of bile acid biosynthesis, compartmentation of bile acid synthesis studied with 3H-labeled ethanol, formation and metabolism of sulfated metabolites of progesterone in human pregnancy, abnormal patterns of these in patients with intrahepatic cholestasis of pregnancy corrected by ursodeoxycholic acid, inherited and acquired defects of bile acid biosynthesis and their treatment, conjugation of bile acids and steroids with N-acetylglucosamine, sulfate-glucuronide double conjugates of hydroxycholesterols, extrahepatic 7alpha-hydroxylation and 3-dehydrogenation of hydroxycholesterols, and extrahepatic formation of C27 bile acids. The final part discusses analysis of free and sulfated steroids in brain tissue by capillary liquid chromatography-electrospray MS and suggests a need for reevaluation of the function of steroid sulfates in rat brain.

Influence of ethinyloestradiol propanolsulphonate on serum bile acids in healthy volunteers

The present work was done to clarify the relevance of altered serum bile acid (BA) profile in healthy women after the administration of the depot oestrogen ethinyloestradiol propanolsulphonate (EES). In the serum of 20 healthy women before and two times after oral EES application, 11 free and 14 taurine- and glycine-conjugated BA were analysed by HPLC with postcolumn derivatisation and fluorescence detection. EES significantly enhanced the total serum BA concentration and that of taurine-conjugated BAs, more pronounced the secondary BAs taurodeoxycholic, tauroursodeoxycholic and taurolithocholic acid. These secondary BAs are produced in the intestine by bacteria due to 7alpha-dehydroxylation of the primary BAs cholic and chenodeoxycholic acid. Because of unchanged free BAs, also produced by intestinal bacteria due to deconjugation, the results were interpreted as a sign of disturbed transport of BAs into the liver. Inhibition of the liver Na(+)-bile salt co-transporter (Ntcp) in the sinusoidal membrane by ethinyloestradiol, formed from the prodrug EES, may be responsible for the altered BA profile in serum.

Contribution of ion-pair complexation with bile salts to the transport of organic cations across LLC-PK1 cell monolayers

PURPOSE

To examine the effect of ion-pair complexation with endogenous bile salts on the transport of organic cations (OCs) across LLC-PK1 cell monolayers.

METHODS

The transport of tributylmethyl-ammonium (TBuMA) and triethylmethylammonium (TEMA) across the cell monolayer was measured in the presence of taurodeoxycholate (TDC), an endogenous organic anion that forms an ion-pair complex with TBuMA, but not with TEMA.

RESULTS

Under proton gradient conditions (i.e., pH 6.0 apical/pH 7.4 basal), the above OCs exhibited similar transport charactersistics, consistent with the well-established OC/H+ antiporter, and the presence of TDC had no measurable effect on the transport of these OCs. Under pH-equilibrated conditions (i.e., pH 7.4 apical/pH 7.4 basal); however. basal to apical transport of TBuMA, not that of TEMA, was increased in the presence of TDC, probably as a result of the formation of a lipophilic ion-pair complex between TBuMA and TDC. The transport and efflux of the TBuMA-TDC complex across the apical membrane of the cell was inhibited by representative substrates of the P-glycoprotein (P-gp), indicating the involvement of P-gp in this process. The increased affinity of the ion-pair complex to P-gp is consistent with a mechanism involving increased transport.

CONCLUSION

In cases where there is no proton gradient between the plasma and urine, the formation of lipophilic ion-pair complexes in the kidney with endogenous bile salts might be involved in the in vivo urinary excretion of large Mw OCs, such as TBuMA.

The human bile salt export pump: characterization of substrate specificity and identification of inhibitors

BACKGROUND & AIMS

The bile salt export pump (BSEP) is the major bile salt transporter in the liver canalicular membrane. Our aim was to determine the affinity of the human BSEP for bile salts and identify inhibitors.

METHODS

Human BSEP was expressed in insect cells. Adenosine triphosphatase (ATPase) assays were performed, and bile salt transport studies were undertaken.

RESULTS

The BSEP gene, ABCB11, was cloned and a recombinant baculovirus was generated. Infected insect cells expressed a 140-kilodalton protein that was absent in uninfected and in mock-infected cells. An ATPase assay showed BSEP to have a high basal ATPase activity. Transport assays were used to determine the Michaelis constant for taurocholate as 4.25 micromol/L, with a maximum velocity of 200 pmol x min(-1) x mg(-1) protein. Inhibition constant values for other bile salts were 11 micromol/L for glycocholate, 7 micromol/L for glycochenodeoxycholate, and 28 micromol/L for taurochenodeoxycholate. Cyclosporin A, rifampicin, and glibenclamide were proved to be competitive inhibitors of BSEP taurocholate transport, with inhibition constant values of 9.5 micromol/L, 31 micromol/L, and 27.5 micromol/L, respectively. Progesterone and tamoxifen did not inhibit BSEP.

CONCLUSIONS

The human BSEP is a high-affinity bile salt transporter. The relative affinities for the major bile salts differ from those seen in rodents and reflect the different bile salt pools. BSEP is competitively inhibited by therapeutic drugs. This is a potentially significant mechanism for drug-induced cholestasis.

Use of ursodeoxycholic acid in liver diseases

Ursodeoxycholic acid is currently the only established drug for the treatment of chronic cholestatic liver diseases. It has cytoprotective, anti-apoptotic, membrane stabilizing, anti-oxidative and immunomodulatory effects. Prolonged administration of ursodeoxycholic acid in patients with primary biliary cirrhosis (PBC) is associated with survival benefit and a delaying of liver transplantation. There is evidence that it might even prevent progression of the histologic stage of PBC. It also has a beneficial effect on primary sclerosing cholangitis, intrahepatic cholestasis of pregnancy, liver disease associated with cystic fibrosis, chronic graft versus host disease, total parenteral nutrition associated cholestasis and various pediatric cholestatic liver diseases. In the present review the current knowledge about the mechanisms of the action and role of ursodeoxycholic acid in the treatment of various liver diseases has been discussed.

Glycosylphosphatidylinositol-specific phospholipase D of human serum--activity modulation by naturally occurring amphiphiles

The enzymatic properties of glycosylphosphatidylinositol-specific phospholipase D (EC 3.1.4.50) were characterized using a 6,000-fold purified enzyme. This was obtained in 100 microg amounts from human serum with a recovery of 35%. Pure alkaline phosphatase containing one anchor moiety per molecule was used as substrate. The enzyme is stimulated by n-butanol, but in contrast to other phospholipases this activation is not produced by a transphosphatidylation reaction. The previously reported non-linearity of the specific activity with respect to phospholipase concentration in the test was no longer observed upon purification, indicating inhibitor removal. The serum inhibitor(s) co-chromatograph with serum proteins and lipoproteins. The main part of the inhibitory activity was found in the lipid fraction after protein denaturation and can be subfractionated into acid phospholipids, cholesteryl esters and triacylglycerides. Added phosphatidyl-serine, phosphatidylinositol, phosphatidylglycerol, gangliosides, cholesteryl esters, and sphingomyelins turned out to be strong inhibitors, as well as phosphatidic acid. Phosphatidylethanolamine and various monoacylglycerols were found to be activators. The low glycosylphosphatidylinositol-specific phospholipase activity found in native serum did not increase significantly upon 90% removal of phospholipids by n-butanol. High serum concentrations of strongly inhibiting compounds, complex kinetic interactions among aggregates of these substances, and compartmentalization effects are discussed as possible reasons for the observed inactivity.

Selenium, zinc and copper plasma levels in intrahepatic cholestasis of pregnancy, in normal pregnancies and in healthy individuals, in Chile

BACKGROUND/AIMS

Low blood Se levels have been previously shown in normal pregnancies (third trimester) and significantly lower levels in patients with intrahepatic cholestasis of pregnancy (ICP), in Finland and in Chile, suggesting that a low or marginal dietary availability of Se may contribute to the pathogenesis of this disease. The aim of this study was to investigate whether a temporal change in plasma concentration of Se, and seasonal fluctuations in plasma concentrations of Se, Zn and Cu, could coincide with changes in the prevalence of ICP.

METHODS

A cross-sectional cohort study was done including 21 ICP patients, 98 women in the third trimester of a normal pregnancy, 29 non-pregnant women, and also 13 individuals (seven non-pregnant women and six men) who had been studied 9 years before. Plasma Se, Zn and Cu were measured by atomic spectroscopy. Plasma Se levels in the present study were compared to the results obtained 5 to 7 years before, employing identical methodology in similar population samples.

RESULTS

Plasma Se concentrations in non-pregnant women were higher than in the previous study: 1.43+/-0.34 micromol/l vs 0.85+/-0.13; p<0.001. In comparison to non-pregnant women, normal pregnancies near term had lower plasma levels of Se: 1.08+/-0.25 micromol/l; p<0.01, and Zn: 17.90+/-3.61 micromol/l vs 19.71+/-3.21; p<0.05, but higher plasma levels of Cu: 34.35+/-7.12 micromol/l vs 20.62+/-3.34; p<0.01. In normal pregnancies, plasma Se concentration was significantly higher in summer (1.34+/-0.19 micromol/l) than in the other seasons, while Zn and Cu diminished. Similar to previous studies, ICP patients had significantly lower Se plasma levels than normal pregnancies: 0.94+/-0.12 micromol/l, p<0.05, and Cu levels were significantly higher: 50.80+/-7.02 micromol/l, p<0.01. Cu plasma levels correlated with the biochemical severity of the disease. Zn did not change in ICP.

CONCLUSIONS

The present study shows that the decrease in the prevalence of ICP in Chile during the last decade coincides with an increase in plasma Se levels. Its lower incidence during summer coincides with a higher plasma Se concentration in summer than in other seasons, as observed in normal pregnancies.

Bile acids and progesterone metabolites in intrahepatic cholestasis of pregnancy

The pathogenesis of intrahepatic cholestasis of pregnancy (ICP) can be related to abnormalities in the metabolism and disposition of sex hormones and/or bile acids, determined by a genetic predisposition interacting with environmental factors. The total amount of oestrogens and progesterone circulating in the blood or excreted in the urine of ICP patients is similar to normal pregnancies. Thus, the search for the cause has been focused on abnormal hormone metabolites. The cholestatic potential of some D-ring oestrogen metabolites is supported by experimental and clinical data. Similar observations with regard to bile acids and progesterone metabolites are still scarce. This article reviews current knowledge in this field, including our own data. Bile acid synthesis appears to be reduced in patients with ICP, in whom primary conjugated bile acids are retained in blood. The major bile acid in blood and urine of these patients is cholic acid instead of chenodeoxycholic acid present in normal pregnancies. Hydroxylation and sulfation of bile acids are enhanced, while glucuronidation appears to be of lesser importance. The synthesis of progesterone appears unimpaired, while the profiles of progesterone metabolites in plasma and urine are different from normal pregnancies, with a larger proportion of mono- and disulfated metabolites, mainly 3alpha,5alpha isomers. Glucuronidated metabolites, however, are unchanged. With the administration of ursodeoxycholic acid (UDCA) to patients with ICP, pruritus and serum liver values are improved, the concentration of bile acids in blood is diminished and the proportion of their conjugated metabolites returned to normal. Simultaneously, the concentration of sulfated progesterone metabolites in blood and their urinary excretion are reduced. The serum levels of bile acids and progesterone metabolites before UDCA administration and their decrease during treatment do not correlate with each other. We propose that patients with ICP have a selective defect in the secretion of sulfated progesterone metabolites into bile and speculate that this may be caused by genetic polymorphism of canalicular transporter(s) for steroid sulfates or their regulation. Interaction with oestrogen metabolites and/or some exogenous compounds may further enhance the process triggering ICP in genetically predisposed individuals.

Drug- and estrogen-induced cholestasis through inhibition of the hepatocellular bile salt export pump (Bsep) of rat liver

BACKGROUND & AIMS

Drug-induced cholestasis is a frequent form of acquired liver disease. To elucidate the molecular pathogenesis of drug-induced cholestasis, we investigated the effects of prototypic cholestatic drugs on the canalicular bile salt export pump (Bsep) of rat liver.

METHODS

Vesicles were isolated from Bsep-, Mrp2-, and Bsep/Mrp2-expressing Sf9 cells. Canalicular plasma membrane (cLPM) vesicles from rat liver and Sf9 cell vesicles were used to study adenosine triphosphate (ATP)-dependent solute uptake by a rapid filtration technique.

RESULTS

Bsep-expressing Sf9 cell vesicles showed ATP-dependent transport of numerous monoanionic bile salts with similar Michaelis constant values as in cLPM vesicles, whereas several known substrates of the multispecific organic anion transporter Mrp2 were not transported by Bsep. Cyclosporin A, rifamycin SV, rifampicin, and glibenclamide cis-inhibited Bsep-mediated bile salt transport to similar extents as ATP-dependent taurocholate transport in cLPM vesicles. In contrast, the cholestatic estrogen metabolite estradiol-17beta-glucuronide inhibited ATP-dependent taurocholate transport only in normal cLPM and in Bsep/Mrp2-coexpressing Sf9 cell vesicles, but not in Mrp2-deficient cLPM or in selectively Bsep-expressing Sf9 cell vesicles, indicating that it trans-inhibits Bsep only after its secretion into bile canaliculi by Mrp2.

CONCLUSIONS

These results provide a molecular basis for previous in vivo observations and identify Bsep as an important target for induction of drug- and estrogen-induced cholestasis in mammalian liver.

Review article: mechanisms of action and therapeutic applications of ursodeoxycholic acid in chronic liver diseases

Ursodeoxycholic acid (ursodiol) is a non-toxic, hydrophilic bile acid used to treat predominantly cholestatic liver disorders. Better understanding of the cellular and molecular mechanisms of action of ursodeoxycholic acid has helped to elucidate its cytoprotective, anti-apoptotic, immunomodulatory and choleretic effects. Ursodeoxycholic acid prolongs survival in primary biliary cirrhosis and it improves biochemical parameters of cholestasis in various other cholestatic disorders including primary sclerosing cholangitis, intrahepatic cholestasis of pregnancy, cystic fibrosis and total parenteral nutrition-induced cholestasis. However, a positive effect on survival remains to be established in these diseases. Ursodeoxycholic acid is of unproven efficacy in non-cholestatic disorders such as acute rejection after liver transplantation, non-alcoholic steatohepatitis, alcoholic liver disease and chronic viral hepatitis. This review outlines the present knowledge of the modes of action of ursodeoxycholic acid, and presents data from clinical trials on its use in chronic liver diseases.

Cholestatic syndromes

Recent advances in cholestatic liver disease have occurred in several areas. Molecular cloning of hepatobiliary transport systems has resulted in the identification of the molecular basis of hereditary and acquired cholestatic syndromes. Apoptosis has been identified as an important mechanism of cholestatic liver injury and bile duct loss. New insights into the pathogenesis of pruritus and fatigue have resulted in new treatment strategies for these debilitating symptoms. Important new studies have been published about pathogenesis, clinical features, and treatment of primary biliary cirrhosis, primary sclerosing cholangitis, cholestasis of pregnancy, and drug-induced cholestasis.

Ursodeoxycholic acid in the treatment of cholestasis of pregnancy: a randomized, double-blind study controlled with placebo

BACKGROUND/AIMS

Intense pruritus and the risk of stillbirths and premature deliveries justify the search for an effective pharmacologic treatment of intrahepatic cholestasis of pregnancy. This study was designed to test the efficacy of ursodeoxycholic acid in maternal pruritus, the biochemical abnormalities and the outcome of pregnancy, in patients with intrahepatic cholestasis of pregnancy of early onset.

METHODS

Pregnant patients hospitalized in a secondary case-referral center with intense pruritus and abnormal serum levels of bile salts and aminotransferases, detected before week 33 of pregnancy, were randomly assigned to receive ursodeoxycholic acid, 1 g per day orally, or an identical placebo, until delivery, in a double-blind study. A 3-week trial period was chosen to compare drug and placebo effects. The follow-up was extended for 3 months after delivery.

RESULTS

Twenty-four patients entered the trial; eight had deliveries before 2 weeks of treatment and one dropped out. The study was then completed in 15 patients: eight received ursodeoxycholic acid and seven placebo. No adverse effects were detected in the mothers or in their babies. After 3 weeks of treatment, patients receiving ursodeoxycholic acid (mean daily dose 16 mg/kg body weight) had a significant improvement in pruritus (p<0.02), in serum bilirubin (0.36+/-0.19 mg/dl (mean+/-SD) versus 0.95+/-0.48 in patients receiving placebo, p<0.01), in aspartate aminotransferase (52+/-42 IU/l vs 98+/-44, p<0.05) and in alanine aminotransferase (54+/-50 IU/l vs 229+/-154, p<0.01); serum total bile salts also tended to be lower in patients receiving ursodeoxycholic acid (26.3+/-33.7 micromol/l vs 55.0+/-44.8, p N.S.). Deliveries occurred at or near term in all mothers who received ursodeoxycholic acid (mean week of pregnancy: 38), while they occurred before week 36 of pregnancy in five patients who received placebo, including one stillbirth. All babies born alive had birth weights adequate for gestational age and they were thriving normally 3 months after delivery.

CONCLUSIONS

Ursodeoxycholic acid is effective and safe in patients with intrahepatic cholestasis of pregnancy of early onset, attenuating pruritus and correcting some biochemical abnormalities in the mothers. Relevant aspects of fetal outcome were also improved in patients receiving ursodeoxycholic acid compared to placebo.