Longitudinal Twin Growth Discordance Patterns and Adverse Perinatal Outcomes.

Objective: The objective of this study was to conduct a longitudinal assessment of inter-twin growth and Doppler discordance, to identify possible distinct patterns, and to investigate the predictive value of longitudinal discordance patterns for adverse perinatal outcomes in twin pregnancies.

Methods: This retrospective cohort study included twin pregnancies followed and delivered at a tertiary University Hospital in London (UK), between 2010 and 2023. We included pregnancies with at least three ultrasound assessments after 18 weeks and delivery after 34 weeks' gestation.

Comparative analysis of long versus short co-incubation of gametes on post-insemination outcomes and embryo morphokinetics.

Research Question: Does a short co-incubation of gametes in conventional IVF affect post-insemination outcomes and embryo morphokinetics?

Design: Sibling oocyte randomized pilot study conducted between December 2020 and March 2023. Eligible couples (n = 55) were women aged 18-43 years with BMI 35 km/m or lower and male normal semen parameters. Cumulus oocyte complexes (COC) (six to 12) were randomized in a 1:1:2 proportion in long (16-18 h) or short (2 h) co-incubation IVF exposure and ICSI, respectively.

Assessing the clinical value of day 7 blastocysts: a predictive model for preimplantation genetic testing for aneuploidy (PGT-A) cycles.

Purpose: To identify the benefit of extending embryo culture until day (D)7 based on patients and cycle characteristics.

Methods: A retrospective cohort study was conducted including 25,120 blastocysts from 5278 PGT-A autologous cycles between 2017 and 2022. A theoretical cumulative live birth rate (CLBR) was calculated by binomial density function.

Steady morphokinetic progression is an independent predictor of live birth: a descriptive reference for euploid embryos.

Study Question: Can modelling the longitudinal morphokinetic pattern of euploid embryos during time-lapse monitoring (TLM) be helpful for selecting embryos with the highest live birth potential?

Summary Answer: Longitudinal reference ranges of morphokinetic development of euploid embryos have been identified, and embryos with steadier progression during TLM are associated with higher chances of live birth.

What Is Known Already: TLM imaging is increasingly adopted by fertility clinics as an attempt to improve the ability of selecting embryos with the highest potential for implantation. Many markers of embryonic morphokinetics have been incorporated into decision algorithms for embryo (de)selection.