P–425 Recurrent pregnancy loss: what can we learn from different international guidelines?

Abstract Study question To which extent do the current international guidelines and recommendations concerning recurrent pregnancy loss (RPL) differ? Summary answer All guidelines apply definitions for RPL, however few diagnostic and therapeutic options are described. Diagnostics should be based on best evidence and current scientific knowledge. What is known already Established risk factors for RPL include anatomical, genetic, endocrine, hemostatic and immune alterations. The European Society of Reproduction and Embryology (ESHRE), American Society of Reproductive Medicine (ASRM), German/Austrian/Swiss Society of Obstetrics and Gynecology (DGGG/OEGGG/SGGG) and the Royal College of Obstetricians and Gynecologists (RCOG) published guidelines concerning diagnostic and therapeutic options in RPL. Due to the different guideline processes and date of publication actuality as well as complexity differ widely. Study design, size, duration We compared the guidelines of the ESHRE, ASRM, DGGG/OEGGG/SGGG and RCOG with regard to definition, diagnostic and therapeutic aspects. The guidelines were published between 2011 and 2018. Structured guideline processes with regular (complete) updates are only provided by the DGGG/OEGGG/SGGG. Participants/materials, setting, methods After thorough literature research (Pubmed, Embase) all existing guidelines and recommendations were analysed and compared considering the current state of knowledge. The RCOG recommendations from 2011 were updated in 2014 and 2017, the ARSM expert letter was last updated in 2012. The ESHRE guideline was published in 2017. The first version of the DGGG/OEGGG/SGGG guideline was published 2006, updated in 2013 and upgraded to a higher evidence-level in 2018 and is currently under review. Main results and the role of chance All guidelines agree that a diagnostic work-up is indicated after at least two clinical pregnancies and should exclude anatomical malformations, an antiphospholipid syndrome and thyroid dysfunction. Furthermore, lifestyle modifications are recommended by all. The general evaluation of an inherited thrombophilia is not recommended by any guideline. Exclusion of other risk factors like parental chromosomal disorders, a polycystic ovary syndrome or insulin resistance are only included in some guidelines, partly due to a lack of diagnostic criteria (luteal phase insufficiency) or due to the different year of publication of the recommendations (e.g. chronic endometritis). All guidelines re