33. COMPARATIVE PILOT STUDY OF SURGICAL ACTIVATION VS APPLICATION OF PLATELET-RICH PLASMA ON OVARIAN FUNCTION IN AN OVINE ANIMAL MODEL
Authors: Sánchez-Mateos S , Fabregues F , Párraga-Ros E , Alvarez I S , Domínguez J A , Méndez M , Ferreri J , Sánchez Margallo F M 
Published: February 2024

Abstract

Introduction
Premature ovarian failure is one of the main problems presented by women with fertility problems. This pathology is characterized by a low ovarian reserve or by the presence of quiescent follicles that for unknown reasons have not been activated and have not been able to carry out their recruitment and subsequent maturation. Recent studies suggest the activation of follicles in a quiescent state capable of being rescued and activated for their function as a possible therapeutic route. Based on this hypothesis, the objective of our study was to verify whether through surgical activation and/or the use of platelet-rich plasma (PRP) these quiescent follicles could be “activated” and reactivate folliculogenesis. For this, and taking into account the similarity between the human and ovine ovary, we used the sheep as an animal model for study.

Methods
To carry out this study, we started with 6 sheep that we divided into 2 groups: group 1 (n=3) surgical activation through small cuts in the ovarian cortex; group 2 (n=3) activation by injection into the ovary of PRP, both interventions in the right ovary leaving the left as control (Figure 1). To evaluate the effect of these two techniques on folliculogenesis, oophorectomies were performed at 2, 4, and 6 months, the ovaries were histologically analysed, and blood samples were taken every 15 days to measure hormones involved in folliculogenesis and ovarian reserve (AMH, FSH, Progesterone and estradiol).

Results
The results obtained in the histological analysis (Figure 2) indicate that after the injection of PRP the highest percentage of primary follicles is obtained 4 months after its injection, beginning to decrease from this moment, while in the case after surgical activation, the percentage of primary follicles gradually increases until reaching its highest percentage at 6 months. Regarding follicular growth, in the case of PRP the highest percentage of growth is obtained at 6 months and in the case of surgical activation at 2 months and then gradually decreases. When evaluating the levels of hormones in the serum of the different groups at different times (Figure 3), we found that in the case of progesterone, the highest levels are achieved after 2 months in both groups, with the values ​​being higher for the group of PRP than surgical activation. For estradiol, the highest levels are obtained at 2 and 6 months, with the levels for the PRP group always being higher, in a similar way occurs with AMH, although there are no differences between the maximum values ​​of the two groups. In the case of FSH, its levels begin to increase until the 4th month, where maximum levels are reached in both groups.

Conclusion
In general we can say that both treatments produce an increase in the number of follicles and their development and an increase in the levels of hormones related to follicular activity and ovarian reserve, although it is not clear which of the two treatments is better.