Accumulation of oocytes from a few modified natural cycles to improve IVF results: a pilot study

Abstract

Purpose To evaluate the role of co-transfer of embryos derived from vitrified oocytes accumulated during the previous modified natural cycles and an embryo developed from the last one as an alternative to repetitive single embryo transfer in a fresh modified natural cycle. Methods Thirty-six patients underwent ICSI procedure with three frozen natural oocytes supplemented by a fresh one obtained from the fourth modified natural cycle. Thirty-one controls received at least three consecutive single embryo transfer in a fresh modified natural cycle. Results In the study group the oocyte retrieval, survival and total fertilization rate were 73.0 %, 78.1 %, and 64.5 %, respectively. Fifty-two embryos were transferred in 29 transfers. In the control group the oocyte retrieval and fertilization rate was 77.4 % and 83.7 %, respectively. Fifty single embryo transfers were performed. Of a total 14 pregnancies obtained in the study group 10 were defined as clinical and 4 as abortions. In the control group a total of 8 single clinical pregnancies and 2 miscarriages were encountered. The overall (20.0 % vs 48.2 %) and the clinical (16.0 % vs 34.4 %) pregnancy rate were significantly higher in the study group having cumulative embryo transfer following the oocyte accumulation. Conclusions These data demonstrate that the co-transfer of embryos derived from vitrified oocytes accumulated during the previous modified natural cycles and an embryo developed from the last fresh modified natural cycle assure an excellent clinical outcome with the overall and clinical pregnancy rate significantly higher compared to the repetitive single embryo transfer in a fresh modified natural cycle.

Cumulative live birth rates in more than 3,000 patients with poor ovarian response: a 15-year survey of final in vitro fertilization outcome

“…Meanwhile, a ''freeze-all embryo'' strategy has also been proposed by some investigators in the use of minimal stimulation protocol (11). Recently a new approach has been proposed by accumulating vitrified embryos during several stimulation cycles to increase the success rates in patients with POR (12,13). For these new protocols, reporting IVF outcomes in the traditional manner has limited usefulness for patients with POR and their physicians as they are more interested in the chance of a live birth for the individual couple versus an entire IVF program.…”

The Conundrum of Poor Ovarian Response: From Diagnosis to Treatment

“…The great advances noted, with regard to oocyte and embryo cryopreservation, since the introduction of vitrification in clinical routine practice, have led the scientific community to investigate a new strategy towards efficiently managing POR patients, namely the “accumulation scenario”. The aim of this strategy is to create a “bank” of frozen oocytes or/and embryos by accumulating them following a number of COS cycles or even via natural or modified natural cycles [ 103 , 104 , 105 , 106 ]. The rationale behind this approach, for managing POR patients, is that the IVF success rate could improve, and the drop-out rate could decrease if the number of available embryos for transfer is increased, mimicking a “normoresponder” status.…”

“…Regarding oocyte accumulation, published data demonstrate that this could be an effective approach towards enhancing IVF outcomes regarding POR patients [ 103 , 105 , 106 ]. These data suggest that oocyte accumulation by vitrification for POR significantly reduces patients’ drop-out rates and IVF cancellation rates, as well as significantly increasing the live birth rate per intention-to-treat patient [ 105 ].…”

Shifting Paradigms in Diminished Ovarian Reserve and Advanced Reproductive Age in Assisted Reproduction: Customization Instead of Conformity

“…67 An Argument for a "Freeze All" Approach in DOR/ARA Patients Recent data are indicating that in the average IVF patient population, frozen embryo transfer may be preferable due its higher pregnancy rate and better pregnancy outcomes as compared with fresh transfers. [68][69][70] However, patients with DOR/ARA may have even more benefits from a freeze-all approach. First, we mentioned previously that older women may be more likely to have anatomic problems such as clinically significant leiomyomata.…”