Intrahepatic cholestasis of pregnancy is associated with an increased risk of gestational diabetes.
OBJECTIVE
To evaluate the association between intrahepatic cholestasis of pregnancy (ICP) and gestational diabetes mellitus (GDM).


METHODS
A retrospective case-control study of pregnancy outcomes in 57,724 women managed at a university teaching hospital in Rhode Island, USA, in whom universal screening for GDM had been performed and who were assessed for the incidence of ICP. Pregnancies complicated by ICP or GDM between February 2005 and June 2011 were identified from the electronic patient records using appropriate ICD codes. A total of 125 cases were required to detect a difference in the incidence of GDM in ICP at 5% significance with 80% power. Demographic and clinical outcome data (including maternal age, ethnic group, BMI, and infant weight and gender) were also collected.


RESULTS
Of the 57,724 pregnancies, 143 were complicated by ICP (0.25%) and 4880 by GDM (8.5%). Nineteen ICP cases had GDM. The incidence of GDM in ICP was 13.6% (19/140, OR 1.68 CI 1.04-2.72). Where gestational ages were available (n=105), of those screened for GDM prior to developing ICP, 13.4% (11/82, OR 1.64 CI 0.88-3.06) had a confirmed diagnosis, rising to 30% (7/23, OR 4.69 CI 1.98-11.1) in cases that were screened following the onset of cholestasis. Simple linear regression analysis of adjusted birth weight centiles in ICP revealed a significant linear trend of increasing centiles with gestational age (p=0.005).


CONCLUSIONS
These data support the hypothesis that the incidence of GDM is higher in women predisposed to developing ICP. It is likely that this susceptibility increases further following the onset of cholestasis.
Division of Obstetric & Consultative Medicine, Women and Infants Hospital, Alpert Medical School of Brown University, Providence, RI 02905, USA; Maternal and Fetal Disease Group, Institute of Reproductive and Developmental Biology, Imperial College, London W12 0NN, United Kingdom. Electronic address: m.martineau@ic.ac.uk.
Marcus
M
Martineau
Division of Research, Women and Infants Hospital of Rhode Island, Providence, RI 02903, USA. Electronic address: craker@wihri.org.
Christina
C
Raker
Division of Obstetric & Consultative Medicine, Women and Infants Hospital, Alpert Medical School of Brown University, Providence, RI 02905, USA; Division of Research, Women and Infants Hospital of Rhode Island, Providence, RI 02903, USA. Electronic address: rpowrie@wihri.org.
Raymond
R
Powrie
Maternal and Fetal Disease Group, Institute of Reproductive and Developmental Biology, Imperial College, London W12 0NN, United Kingdom; Women's Health Academic Centre, Kings College London, 2nd Floor Hodgkin Building, King's College London, Guy's campus, London SE1 1UL, United Kingdom. Electronic address: catherine.williamson@kcl.ac.uk.
Catherine
C
Williamson
D000328:Adult; D016022:Case-Control Studies; D002780:Cholestasis, Intrahepatic / Q000150:complications / Q000453:epidemiology* / Q000208:ethnology; D016640:Diabetes, Gestational / Q000453:epidemiology* / Q000208:ethnology; D005260:Female; D020022:Genetic Predisposition to Disease; D005865:Gestational Age; D006630:Hispanic or Latino / Q000706:statistics & numerical data; D006801:Humans; D011247:Pregnancy; D011248:Pregnancy Complications / Q000453:epidemiology* / Q000208:ethnology; D011256:Pregnancy Outcome; D012189:Retrospective Studies; D012237:Rhode Island / Q000453:epidemiology; D012306:Risk
Bile acids; Gestational diabetes; Glucose tolerance; Intrahepatic cholestasis of pregnancy