P-277 Can a validated, livebirth predictive, in-house morphokinetic algorithm, score embryos according to maternal age; providing more information, for patients, regarding chance of success?
Authors: Smith R , Barrie A , Berrisford K , Davis N , Duffy S , Corcoran S , Montgomery S , Oakley R , Owen S , Campbell A 
Published: June 2023

Study question

How does a livebirth (LB) prediction algorithm, built in-house on data from 6228 known outcomes from all ages, perform when categorised by female age?

Summary answer

The algorithm scored and ranked embryos accurately for clinical outcome (FH) regardless of female age; with proportions of poor prognosis embryos highest in older patients.

What is known already

Time-lapse incubation enables development of predictive algorithms using key morphokinetic variables to score embryos according to potential for clinical outcomes. Maternal age is associated with embryo quality and implantation. Understanding whether kinetic events are influenced by increasing age may benefit embryo selection and patient information provision. There is little evidence of a correlation between advancing maternal age and morphokinetics, although incidence of abnormal cleavage is linked to aneuploidy and reduced blastulation. Predictive algorithms are generally applied to embryos irrespective of oocyte age but are they effective in selecting the optimum embryo for transfer comparatively across differing maternal age groups?

Study design, size, duration

A retrospective, comparative analysis of 10034 transferred embryos from 2011 to 2022 in 11 sister fertility clinics. Embryos were cultured for 4 - 6 days in time-lapse incubation before transfer (Embryoscope, Vitrolife). A score was derived using a prospectively validated in-house statistical algorithm, assessing 6 manually annotated morphokinetic variables (t3,t4,t5,t8,tSB,and tB) and trophectoderm grade. Embryos were scored 1 to10 for increasing live birth (LB) potential.

Participants/materials, setting, methods

All transferred embryos were assessed for age of the patient or donor at treatment, traceable to an algorithm score (1-10) with known implantation, defined by presence of fetal heart (KID-FH). Embryos were assigned to two age groups, &lt; 38 years (n6948) or &gt; = 38 years (n3086) and compared according to the distribution of algorithm scores. Comparative significance of the two groups, against each other and the whole cohort, was assessed for significance using chi-squared.

Main results and the role of chance

Comparison of the KID-FH per score, for age groups revealed increasing implantation rates and effective ranking per score in each age group, &lt;38 KID-FH scores 1 to10; 9.6%,17.8%, 25.7%, 24.3%, 28.3%, 38.2%, 41.4%, 48.4%, 54.6% and 57.8% and for &gt; = 38 score 1-10; 2.0%, 3.8%, 5.9%, 9.9%, 10.8%, 17.9%, 22.2%, 22.0% 31.6% and 36.8%.

KID-FH increased incrementally with increasing score in both maternal age groups, demonstrating that the algorithm is predictive irrespective of maternal age.

The percentage incidence of scores were compared, &lt;38 years, score 1 to 10; 3.8%, 4.6%, 4.5%, 5.0%, 6.2%, 7.5%, 9.3%, 12.4%, 16.8%, 29.8% versus &gt; = 38 years 1 to 10; 8.0%, 9.4%, 7.1%, 9.2%, 8.7%, 9.4%,10.5%,11.0%, 11.2%,15.4%. There were significantly higher numbers of embryos with lower scores (p = 0.01) in the &gt; = 38 age group (scores 1-6) than the &lt;38 age group. The younger ages conversely, had significantly greater high scoring embryos 9-10, (p = 0.01), score 7 to 8 were comparable across the age groups.

The algorithm score is effective in determining implantation potential irrespective of maternal age. Embryos with poorer implantation potential are present in significantly greater numbers in the older age group and this age group attains significantly fewer high potential embryos when compare to younger patient embryos.

Limitations, reasons for caution

The data for this analysis was determined from multiple clinics within a fertility group operating under uniform practices. The derived algorithm variables and outcomes may not be transferable to another clinic setting. Follow up is required for known live birth outcomes to confirm comparative prediction to KID-FH per age group.

Wider implications of the findings

The algorithm score infers embryo competence irrespective of age with differences existing only in the prevalence of low and high scores. This algorithm differentiation promises to inform clinicians and patients regarding their chance of success, when utilised to assess embryos. Morphology alone does not have this breadth or predictive capability

Trial registration number

N/A