Acute pyelonephritis during pregnancy: a systematic review of the aetiology, timing, and reported adverse perinatal risks during pregnancy.

We performed a comprehensive systematic review of acute pyelonephritis in pregnancy using PubMed, SCOPUS, ClinicalTrials.gov, and Ovid from inception to April 2018. About 7796 references were screened for inclusion, and 52 references from 1908 to 2017 were included.