TY - JOUR T1 - Endometrial Dating Method Detects Individual Maturation Sequences During the Secretory Phase JF - In Vivo JO - In Vivo SP - 1951 LP - 1963 DO - 10.21873/invivo.11992 VL - 34 IS - 4 AU - JOACHIM ALFER AU - AMIR FATTAHI AU - NATHALIE BLEISINGER AU - JÜRGEN KRIEG AU - ROLF BEHRENS AU - RALF DITTRICH AU - MATTHIAS W. BECKMANN AU - ARNDT HARTMANN AU - IRMGARD CLASSEN-LINKE AU - ROXANA M. POPOVICI Y1 - 2020/07/01 UR - http://iv.iiarjournals.org/content/34/4/1951.abstract N2 - Background/Aim: This study assessed whether a new immunohistochemical dating method allows precise endometrial dating allowing optimal timing for embryo transfer. Patients and Methods: A novel method was used for endometrial dating, with parameters including menstrual cycle days, Noyes histological criteria, along with immunohistochemical expression pattern of estrogen and progesterone receptors and proliferation marker Ki-67. Endometrial maturation was analyzed on days +5 to +10 after ovulation or progesterone administration in 217 biopsies from 151 subfertile patients during the secretory phase. Results: Endometrial maturation varied individually, occurring 1.68±1.67 days late. Comparison of histological maturation with clinical days after ovulation showed a delay of about 2 days. Conclusion: Endometrial maturation requires 8 days, rather than the expected 6 days, to reach the histological mid-secretory phase. This is not a delay and is also seen in fertile patients. The new analysis method used is superior to that using Noyes criteria alone and provides a better basis for determining conditions for optimal timing of embryo transfers. ER -