O-187 Real-word data on effectiveness of ICSI over conventional IVF according to infertility factors based on human fertilisation and embryology authority dataset
Authors: Paffoni A , Corti L , Vitagliano A , Vigano P 
Published: July 2024

Abstract

Study question
Can the analysis of Human Fertilisation and Embryology Authority (HFEA) dataset provide real-word data on effectiveness of ICSI over conventional IVF according to infertility factors?

Summary answer
A statistically significant reduction in live birth rate was shown to be associated with ICSI use in cycles with female infertility factors.

What is known already
The adoption of ICSI has seen a considerable increase over the years, even in cases without an evident male-factor infertility. Available studies including large retrospective studies and meta-analyses evaluating the effectiveness of the two strategies tend to support the idea that in the absence of a male factor, ICSI does not offer a significant advantage over conventional IVF(cIVF). However, some uncertainties still exist regarding live birth rates and in relation to various infertility factors.

Study design, size, duration
Retrospective study of 275.825 first cycles treated with cIVF or ICSI between 2005-2018, included in the HFEA database. Infertility indications were simplified into three groups: 1) female only (endometriosis, tubal, ovulatory and cervical factors); 2) male (male only or with male and female factors together); 3) unexplained infertility. The primary outcome was live birth rate in the first fresh cycle. Secondary outcomes included fertilization, implantation, miscarriage rates, cycle cancellation rate and neonatal outcomes.

Participants/materials, setting, methods
Outcomes were evaluated through binomial logistic regression including the following predictors: female age, inseminated oocytes, number/stage of transferred embryos (condensed with principal component analysis), subtype of female infertility, year of treatment. A paired-analysis was also performed matching couples in a 1:1 ratio between ICSI and conventional IVF based on female age, indication, inseminated oocytes, year of treatment. Results were reported according to infertility cause using crude and adjusted Odds Ratios (OR) with 95%CI.

Main results and the role of chance
The study revealed a consistent balance in treatment distribution between conventional IVF and ICSI, with a slight increase in ICSI cycles in recent years. Based on logistic regression analysis, a significant reduction in live birth rate was demonstrated using ICSI compared to conventional IVF in cycles with female factors (adjusted OR = 0.95, 95%CI: 0.91-0.99). No significant differences emerged in unexplained factor cycles. With the use of conventional IVF, the overall odds of having a total fertilization failure increased by a factor of 1.84 (95%CI: 1.75-1.94). No significant differences in implantation rates between conventional VF and ICSI were seen after adjustment. The OR for male sex in newborns compared to female sex from single pregnancies was significantly influenced by ICSI use across the three groups of infertility causes and ranged between 0.84 and 0.87. The matched dataset confirmed a reduced occurrence of live birth per cycle in case of female factors (aOR=0.91, 95%CI: 0.86-0.96) and an overall significant lower proportion of cycles ending in cancellation for absence of viable embryos using ICSI compared to conventional IVF.

Limitations, reasons for caution
Some biases are intrinsic in the availability and quality of retrospective data obtained from registries and unmeasured confounders may influence the generalizability of the results. The study does not provide information on cumulative live birth rates.

Wider implications of the findings
ICSI introduces an additional, invasive step in assisted reproduction with a potential reduction in live birth rates for specific patients’ groups. These findings emphasize the importance of tailoring treatments to specific patient profile.The routine use of ICSI for all cases should not be considered an appropriate clinical practice.

Trial registration number
not applicable