key: cord-0715799-xwlxuqfh
authors: Sun, Hong
title: Adjustment is Required to Calculate the Risk of Early Pregnancy Loss with Covid-19 Infection or Vaccination
date: 2021-08-03
journal: Am J Obstet Gynecol
DOI: 10.1016/j.ajog.2021.08.002
sha: eb0d370c4318673c0130d1d8cd436090328bb743
doc_id: 715799
cord_uid: xwlxuqfh

nan

the possible infection that led to their enrollment in the study, the EPL risk during this 35 period of delay is avoided in the reported study. Moreover, the period of early 36 pregnancy consists of weeks with high EPL risk 2,3 . The necessity to make such an 37 adjustment is also supported by the statistics presented in the study: among those 6 38 reported EPL events, 5 EPLs occurred at 7-12 weeks and one at 15 weeks, none of the 39 EPL happened on week 5 and 6, which are normally considered as the weeks with the 40 highest EPL risk 2,3 .

Suppose the participants of the study were equally distributed between week 5 43 (diagnosis of pregnancy) and week 14 (enrollment deadline) at their enrollment, their week 20) 3 . Therefore, the adjusted EPL risk reported in the study should be doubled, which means the adjusted EPL risk should be 12% instead of 6%, which is still an 48 acceptable level. If the authors could include the actual gestation week during 49 enrollment in the study, it is possible to make a more accurate estimation of adjusted 50 EPL risk. 

rates using life table analysis. Birth Defects Research Part A: Clinical and 68 Molecular Teratology

Preliminary findings of mRNA Covid-71 19 vaccine safety in pregnant persons