Perinatal outcomes with intrahepatic cholestasis of pregnancy in twin pregnancies

<i>Objective</i>: To describe perinatal outcomes of twin pregnancies complicated by intrahepatic cholestasis of pregnancy (ICP). <i>Methods</i>: We conducted a retrospective cohort study of women delivered at a large tertiary obstetric center in Shanghai, China from January 2006 to May 2014. Delivery data were abstracted from medical records of all twin gestations delivered at the hospital. <i>Results</i>: A total of 129/1922(6.7%) twin and 1190/92 273 singleton (1.3%) pregnancies were complicated by ICP. An increased risk of stillbirth among twin pregnancies was observed (3.9% and 0.8% in the ICP and non-ICP groups, respectively; aOR 5.75, 95% CI 2.00–16.6). Stillbirths with ICP and twins occurred between 33 and 35 weeks gestation compared to 36–38 weeks gestation among singletons. ICP in twins was also associated with an increased risk of preterm birth (&lt;37 weeks) with an aOR of 4.17 (95% CI 2.47–7.04) and an aOR of 1.89 (95% CI 1.26–2.85) for delivery &lt;35 weeks. Twin pregnancies complicated by ICP also had increased meconium staining of amniotic fluid and lower birth weight. <i>Conclusions</i>: Twin pregnancies with ICP have significantly increased risks of adverse perinatal outcomes including stillbirth and preterm birth. Stillbirth occurs at an earlier gestational age in twin gestation compared to singletons, suggesting that earlier scheduled delivery should be considered in these women.

【研究目的】：阐明并发妊娠肝内胆汁淤积症（intrahepatic cholestasis of pregnancy, ICP）的双胎妊娠的围产结局。
【研究方法】：本研究针对2006年1月至2014年5月间，在中国上海某大型三级产科中心分娩的孕妇开展回顾性队列研究。研究数据从本院所有双胎妊娠分娩的医疗记录中提取。
【研究结果】：共计129/1922（6.7%）例双胎妊娠及1190/92273（1.3%）例单胎妊娠并发ICP。观察发现双胎妊娠的死胎风险升高：ICP组与非ICP组死胎率分别为3.9%与0.8%，校正优势比（adjusted odds ratio, aOR）为5.75，95%置信区间（95% confidence interval, 95% CI）为2.00~16.6。并发ICP的双胎妊娠死胎发生于孕33~35周，而单胎妊娠死胎多发生于孕36~38周。双胎合并ICP还与早产（孕<37周）风险升高相关，其校正优势比为4.17（95%CI 2.47~7.04）；针对孕<35周分娩的校正优势比为1.89（95%CI 1.26~2.85）。此外，并发ICP的双胎妊娠还存在羊水胎粪污染发生率升高、新生儿出生体重更低的情况。
【研究结论】：并发ICP的双胎妊娠发生包括死胎、早产在内的不良围产结局的风险显著升高。与单胎妊娠相比，双胎妊娠的死胎发生孕周更早，提示应对此类孕妇考虑实施更早的计划性分娩。