Pregnancy outcome in women undergoing liver biopsy during pregnancy: A nationwide population-based cohort study.

UNLABELLED: Liver biopsy is an important procedure in the investigation of liver disease. We examined pregnancy outcomes in women who underwent liver biopsy during pregnancy. In a nationwide population-based cohort study we linked data from the Swedish Medical Birth Registry (for births between 1992 and 2011) with those from the Swedish Patient Registry. We identified 23 pregnancies exposed to liver biopsy. We calculated relative risks (RRs) for adverse pregnancy outcomes according to liver biopsy status using 1,953,887 unexposed pregnancies with and without a record of liver disease as reference. Our main outcome measures were stillbirth and preterm birth. There were no stillbirths in pregnancies exposed to liver biopsies compared with 0.3% stillbirths in unexposed pregnancies, and 3/23 (13%) exposed pregnancies were preterm (RR, 2.6; 95% confidence interval, 0.9-7.5). Compared to women with a record of liver disease, preterm birth was not increased in those exposed to liver biopsy (RR, 0.9; 95% confidence interval, 0.1-6.0). Except for an increased risk of small for gestational age birth in pregnancies exposed to liver biopsy (RR, 5.2; 95% confidence interval, 1.8-14.8), other adverse pregnancy outcomes were independent of liver biopsy status when the analysis was restricted to women with a diagnosis of liver disease. Compared with unexposed sibling pregnancies, pregnancies with a liver biopsy were 7 days shorter, but birth weights did not differ between the siblings (-67 g; P > 0.05).

CONCLUSION: Apart from a moderately increased risk of preterm birth and small for gestational age, there was no association between liver biopsy during pregnancy and adverse pregnancy outcome; potential excess risks should be weighed against the advantages of having a liver biopsy that may influence clinical management of the patient and indirectly fetal health. (Hepatology 2017).