Fig 1.
The figure illustrates the two compared ovarian hyperstimulation regimens.
In the upper part of the figure, the regimen used in 2019. Women received corifollitropin-alfa and 6–7 days later recombinant FSH daily, if necessary. Since the observation of a leading follicle with a mean diameter above 13–14 mm, they were prescribed also GnRH antagonist daily. The final maturation was obtained with GnRH agonist 0.2 mg. In the lower part of the figure, the regimen used in 2020 (progestin-primed ovarian stimulation). Women received both hMG and oral MPA daily. Final oocytes maturation was obtained with the concomitant administration of GnRH agonist 0.2 mg, plus hCG 1,000 IU. GnRH: Gonadotropin Releasing hormone. Cor-α: Corifollitropin-alfa. GnRH ant: GnRH antagonist. GnRHa: GnRH agonist. rFSH: recombinant FSH. MPA: medroxy-progesterone acetate. hMG: human Menopausal Gonadotropin. hCG: human Choriogonadotropin.
Table 1.
Baseline clinical characteristics of the study groups.
Fig 2.
Ratio of oocytes retrieved per serum AMH (reported in ng/ml).
The left part of the figure refers to the total number of oocytes retrieved. The right part refers to the total number of mature oocytes retrieved and thus cryopreserved. The first study period (simplified in the figure with GnRH ant, to underline the use of GnRH antagonists) is depicted in red. The second study period (simplified in the figure with PPOS, corresponding to progesterone primed ovarian stimulation) is depicted in blue. No statistically significant difference emerged for both comparisons (p = 0.76 and p = 0.80, respectively).
Table 2.
Baseline clinical characteristics of the study groups.
Table 3.
follicular fluid steroids concentration in the two study periods, presented separately according to the concomitant assumption of letrozole.
Fig 3.
The follicular fluid steroids cascade in the two study groups.
Data are presented separately for those who did (lower panel) and did not (higher panel) receive letrozole. Statistically significant increases were highlighted in yellow. Statistically significant decreases are highlighted in green (for details, see Table 3).