Predicting personalized cumulative live birth rate after a complete in vitro fertilization cycle: an analysis of 32,306 treatment cycles in China
Authors: Xia Leizhen , Han Shiyun , Huang Jialyu , Zhao Yan , Tian Lifeng , Zhang Shanshan , Cai Li , Xia Leixiang , Liu Hongbo , Wu Qiongfang 
Published: October 2023

Objective: To develop and validate a set of predictive models
to estimate the individual chances of cumulative live birth at different
time points of a complete IVF cycle. Design: Retrospective
cohort study. Setting: Reproductive Medicine Center of Jiangxi
Maternal and Child Health Hospital Affiliated to Nanchang Medical
College, Nanchang, China. Population: A total of 32,306
complete cycles derived from 29,023 couples undergoing IVF treatment
from 2014 to 2020 were included. Methods: Three predictive
models of CLBR were developed based on three phases of a complete cycle:
pre-treatment, post-stimulation, and post-treatment. The non-linear
relationship was treated with restricted cubic splines. Subjects from
2014 to 2018 were randomly divided into a training set and a test set at
a ratio of 7:3 for model derivation and internal validation, while
subjects from 2019 to 2020 were used for temporal validation.
Main outcome measures: cumulative live birth rate.
Results: Predictors of pre-treatment model included female age
(non-linear relationship), antral follicle count (non-linear
relationship), body mass index, number of previous IVF attempts, number
of previous embryo transfer failure, type of infertility, tubal factor,
male factor, and scarred uterus. Predictors of post-stimulation model
included female age (non-linear relationship), number of oocytes
retrieved (non-linear relationship), number of previous IVF attempts,
number of previous embryo transfer failure, type of infertility, scarred
uterus, stimulation protocol, as well as endometrial thickness,
progesterone and luteinizing hormone on trigger day. Predictors of
post-treatment model included female age (non-linear relationship),
number of oocytes retrieved (non-linear relationship), cumulative Day-3
embryos live-birth capacity (non-linear relationship), number of
previous IVF attempts, scarred uterus, stimulation protocol, as well as
endometrial thickness, progesterone and luteinizing hormone on trigger
day. The C index of the three models were 0.7559, 0.7744, and 0.8270,
respectively. All models were well calibrated ( p = 0.687,
p = 0.468, p = 0.549). In internal validation, the C index
of the three models were 0.7422, 0.7722, 0.8234, respectively; and the
calibration P values were all greater than 0.05. In temporal validation,
the C index were 0.7430, 0.7722, 0.8234 respectively; however, the
calibration P values were less than 0.05. Conclusion: This
study provides three IVF models to predict CLBR according to information
from different treatment stage, and these models have been converted
into an online calculator
(https://h5.eheren.com/hcyc/pc/index.html#/home). Internal validation
and temporal validation verified the good discrimination of the
predictive models. However, temporal validation suggested low accuracy
of the predictive models, which might be attributed to time-associated
amelioration of IVF practice.