High DFI predicts lower cumulative live birth rate in couples undergoing ART: Study
IVF/ICSI treatments are resource-consuming, both because of the costs of the treatments as well as the loss of working hours. Therefore, to minimize the burden on patients as well as on society, it is important to make the ART treatments as efficient as possible in terms of the live birth rate (LBR).
Today, the choice between ICSI and standard IVF is mainly based on the results of a conventional semen analysis, the concentration and motility of the spermatozoa in the raw semen sample as well as after gradient centrifugation or a swim-up procedure. Other factors, such as poor fertilization/outcomes by standard IVF, may lead to a switch to ICSI in subsequent cycles.
Several studies showed that a high sperm DNA fragmentation index (DFI) was associated with a poor ART outcome. It is still a matter of debate whether DFI testing should be routinely performed in patients undergoing ART. One of the obstacles to making cost-benefit analyses in relation to applying DFI measurements as a standard procedure is that the available data are based on single cycles, not taking into consideration the complexity of ART procedures with multiple cycles and mixing of IVF and ICSI as well as fresh and frozen embryo transfers offered to a couple. Therefore, the cumulative LBR (CLBR), including all treatments offered to a couple, may be a better measure for the outcome of ART.
The primary aim of the study conducted by Voncina and team was to investigate the impact of a high DFI on the CLBR depending on whether the first ART treatment was IVF or ICSI. As secondary aims, authors investigated the impact of the DFI on fertilization rates (FRs) in IVF and ICSI treatments and, additionally, on the miscarriage rate.
The data were derived from a longitudinal cohort study of ART cycles between 2007 and 2017 at the tertiary fertility Reproductive Medicine Centre (RMC), Skane University Hospital in Malmo, Sweden. A total of 2,713 infertile couples who underwent assisted reproductive technology treatment between 2007 and 2017 were included in the study. All in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) treatments (up to three fresh treatments and all associated frozen-thawed embryo transfers) offered to the couples by the public health care system were included, in total 5,422 cycles.
In the IVF group, the CLBR values were higher for couples with normal DFI compared with those for couples with high DFI (>20%) (48.1% vs. 41.6% for conservative CLBR estimate and 55.6% vs. 51.4% for optimal CLBR estimate after adjustment for female age, respectively). No DFI-dependent difference was seen in the ICSI group.
When a DFI of 40% was used as the cutoff value, the miscarriage rate was 31.3% in the group in which the first DFI value was <40% in comparison with 39.1% in the group in which the DFI was >40% (P = .195).
Authors found that couples with a sperm DFI >20%— compared with those with lower DFI values—obtained a lower CLBR when standard IVF was used as the ART method for the first treatment cycle, whereas this was not true for ICSI treatment. In addition, they found that this difference can—at least partly—be explained by a negative association between the DFI and the IVF fertilization rate in IVF but not in ICSI procedures.
Usually, the method of fertilization applied in the first ART cycle is to a high degree decided by a standard semen analysis performed on the raw ejaculate and after swim-up or a gradient centrifugation procedure. In the case of treatment failure in the first or any subsequent cycle, the standard IVF can be altered to ICSI, e.g., because of poor fertilization and/or on patient request. Thus, an important question is whether introducing a new criterion for selecting the optimal method for the first ART procedure will have any impact on the CLBR.
In conclusion, this data indicated that the use of standard IVF in the first ART cycle—in a setup of three complete treatment cycles offered to a couple—implied a lower CLBR in cases with a DFI R20% compared with that of those with a DFI below this level.