Document Type : Original Article
Department of Biostatistics, School of Paramedical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Safety Promotion and Injury Prevention Research Center, Department of Epidemiology, School of Public Health and Safety, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Department of Endocrinology and Female Infertility, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
Department of Biostatistics, School of Public Health, Iran University of Medical Sciences, Tehran, Iran
Reproductive Epidemiology Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
Background: Women who undergo in vitro fertilization (IVF) cycles should successfully go via multiple stages (i.e.,
clinical pregnancy, no abortion under 12 weeks, no abortion under 20 weeks, and delivery) to achieve a live birth. In
this study, data from multiple IVF cycles and its multiple stages were reanalyzed to illustrate the success factors associated
with various stages of IVF cycles in a population of Iranian infertile women.
Materials and Methods: This historical cohort study includes 3676 assisted reproductive technology (ART) cycles.
Covariates take into account in this study were women’s age, type of infertility (primary, secondary), body mass index
(BMI), cause of infertility, history of abortion, duration of infertility, number of oocytes, number of embryos, fertilization
rate, semen factors (Spermogram) and having polycystic ovarian syndrome (PCOS) during IVF cycles. Joint modeling
was fitted to apply informative cluster size.
Results: Increasing age un women was associated with an increase in the BMI and a positive history of abortion and
PCOS, and also, an increase in the number of treatment cycles, while in men was associated with the negative spermogram.
With the increase in the number of treatment cycles, the result of the IVF success decreased, but with the
increase in the number of embryos, fertilization rate and also, quality and / or quantity parameters of spermogram, we
encountered with an increase in the IVF success rate.
Conclusion: It seems that a joint model of the number of treatment cycles and the result of IVF is a valuable statistical model
that does not ignore the significant effect of cycle numbers, while this issue is ignored usually in the univariate models.