Parole chiave
Multi-oocyte follicles
follicle fusion
Granulosa Cell
Ovary
Abstract
Introduction: Significant progress has been made in understanding oocyte fertilization and early developmental stages through in vitro fertilization (IVF) techniques. However, irregularities such as conjoined oocytes and binucleate giant oocytes, which are exceptions to the normal rule of one diploid female gamete per follicle, can potentially lead to chromosomal disorders in embryos and are recommended to be excluded from IVF attempts. The formation of primordial follicles during ovarian development, known as follicle assembly, is a critical process that establishes the ovarian follicle reserve. Multi-oocyte follicles (MOFs) containing two or more oocytes have been observed in various species, including humans, and their clinical significance on fertility and reproductive health remains unclear. Genetic and environmental factors, such as gene knockout and exposure to endocrine disruptors, have been implicated in MOF formation, but the mechanisms are not fully understood and require further investigation.
Material & Method: In this Observational study, 350 slides of ovarian tissues were scanned using an AI-based automated microscope, Grundium Ocus 20, and the TIFF images were stored in cloud storage. The slides were examined using third-party software, Pathcore Seeden Viewer, for morphometry of binovular follicles.
Results: Out of the 350 slides, 22 slides from 7 different ovarian tissues were found to have binovular as well as multinovular oocytes.
Discussion: Multiple Ovarian Follicles (MOFs) are rare occurrences in the ovaries characterized by the presence of two or more oocytes within a single follicle. MOFs are believed to be primarily caused by the non-separation of multiple oocytes during the proliferation of cortical sex cords in developing ovaries, which is regulated by various factors including follicle-stimulating hormone (FSH)/inhibin, bone morphogenetic protein-15 (BMP-15)/growth differentiation factor-9 (GDF-9), and germ cell nuclear factor (GCNF). Dysregulation of these factors, as well as exposure to environmental factors such as diethylstilbestrol (DES) and isoflavones, may contribute to the development of MOFs. Binovular oocytes, formed when two separate oocytes are released from the ovary during ovulation and fertilized by two different sperm, can lead to non-identical twins. Binovular twinning is linked to genetic and environmental factors, including maternal age, heredity, hormonal imbalances, epigenetic factors, and assisted reproductive techniques such as in vitro fertilization (IVF). Polynuclear oocytes, which contain more than one nucleus, can occur during oocyte maturation and have been associated with molecular factors such as abnormalities in the meiotic spindle, cytoskeleton defects, and mitochondrial dysfunction, as well as environmental factors such as exposure to toxins, stress, and hormonal imbalances. Proper identification and examination of binovular and polynuclear oocytes during oocyte retrieval in assisted reproductive technology (ART) and infertility centers are crucial for successful outcomes and to avoid potential risks and complications. Understanding the underlying molecular and environmental factors associated with these unique oocyte characteristics can provide valuable insights into oocyte development and maturation processes, and help improve ART outcomes by better understanding the causes of infertility and developing strategies accordingly.