The total pregnancy potential per oocyte aspiration after assisted reproduction—in how many cycles are biologically competent oocytes available?

Abstract

Purpose While stimulation of women prior to assisted reproduction is associated with increased success rates, the total biological pregnancy potential per stimulation cycle is rarely assessed. Methods Retrospective sequential cohort study of the cumulative live birth rate in 1148 first IVF/ICSI-cycles and 5-year follow up of frozen embryo replacement (FER) cycles were used. Oocyte number, number of embryos transferred, and cryopreserved/ thawed and transferred embryos in a FER cycle were registered for all patients. Children per oocyte and per transferred embryo and percentage of cycles with births were calculated. Results We obtained 9529 oocytes. Embryos (2507) were transferred in either fresh or FER cycles, resulting in 422 births and 474 live born children. Median age of the women was 32.5 years (range 20-41.5 years). In total, 34.3 % of all cycles ended with a live birth while in 65.7 % of the cycles, no oocytes were capable of developing into a child. The average number of oocytes needed per live born child after transfer of fresh and thawed embryos was 20 as only 5.0 % of oocytes aspirated in the first IVF/ICSI cycle had the competence to develop into a child. Conclusions In our setting, overall 5.0 % of the oocytes in a first cycle were biologically competent and in around 2/3 of all cycles, none of the oocytes had the potential to result in the birth of a child.

The Vienna consensus: report of an expert meeting on the development of art laboratory performance indicators†‡

“…Not all oocytes collected from a patient following ovarian stimulation for ART will have the same developmental competence, which is illustrated by the observation that only 5% of oocytes collected eventually result in a live birth (Lemmen et al , 2016). Intrinsic oocyte competence is derived not only from the degree of nuclear maturity of the oocytes, but also from their cytoplasmic maturity (Patrizio and Sakkas, 2009; Garrido et al , 2011; Lemmen et al , 2016). Furthermore, oocyte developmental competence is affected by a range of intrinsic patient-related and external factors.…”

Intrinsic fertility of human oocytes

“…Previous reports by necessity were unclear on this metric, where the pregnancy or live baby rate per oocyte was based on ovarian stimulation IVF cycles, with leftover embryos, and thus a predictive model could not be developed and the live baby rate per oocyte might be underestimated (20)(21)(22)(23)(24). In frozen oocyte reports, it was assumed that about 6.5% of oocytes would result in a live baby, which would mean a woman would need about 32 oocytes frozen to be likely to have a baby and about 40 oocytes to have a 97.5% chance of having a baby.…”

The Vienna consensus: report of an expert meeting on the development of ART laboratory performance indicators

“…Not all oocytes collected from a patient following ovarian stimulation for ART will have the same developmental competence, which is illustrated by the observation that only 5% of oocytes collected eventually result in a live birth (Lemmen et al, 2016). Intrinsic oocyte competence is derived not only from the degree of nuclear maturity of the oocytes, but also from their cytoplasmic maturity (Garrido et al, 2011;Lemmen et al, 2016;Patrizio and Sakkas, 2009). Furthermore, oocyte developmental competence is affected by a range of intrinsic patient-related and external factors.…”