Related Experiment Video
Updated: Jun 3, 2026
07:27
Accurate Follicle Enumeration in Adult Mouse Ovaries
Published on: October 16, 2020
Correlation of oocyte morphometry parameters with woman's age
Claudia Valeri1, Sebastiana Pappalardo, Massimo De Felici
1Genesis Centre for Reproductive Medicine, via Velletri 7, 00198, Rome, Italy.
Journal of Assisted Reproduction and Genetics
|April 7, 2011
Summary
High zona pellucida birefringence correlates with thicker zona and narrower perivitelline space in oocytes. Oocyte size and zona pellucida thickness decrease with increasing maternal age.
Area of Science:
- Reproductive biology
- Oocyte morphology
- Human embryology
Background:
- Oocyte quality is crucial for successful fertilization and embryo development.
- Morphometric parameters of oocytes, such as cytoplasm diameter (CD), zona pellucida thickness (ZPT), and perivitelline space (PS) width, are indicators of oocyte health.
- Zona pellucida birefringence and spindle presence are also important factors influencing oocyte quality.
Purpose of the Study:
- To investigate the relationship between zona pellucida birefringence, spindle presence, and morphometric parameters (CD, ZPT, PS) in human oocytes.
- To evaluate the impact of maternal age on these oocyte characteristics.
Main Methods:
- Oocytes were categorized based on zona pellucida birefringence (low or high) and spindle presence (present or absent).
- Morphometric parameters including cytoplasm diameter, zona pellucida thickness, and perivitelline space width were measured.
- Statistical analysis was performed to assess correlations between these parameters and maternal age.
Main Results:
- Oocytes with high zona birefringence (HZB) exhibited thicker zona pellucida compared to those with low zona birefringence (LZB).
- The perivitelline space was narrower in HZB and oocytes with a visible spindle (SP) compared to LZB and oocytes without a visible spindle (aSP), respectively.
- Both cytoplasm diameter and zona pellucida thickness showed a significant linear decrease with increasing maternal age.
Conclusions:
- There is a significant association between zona pellucida birefringence, spindle status, and specific morphometric parameters in human oocytes.
- Oocyte size and zona pellucida thickness diminish with advancing maternal age, highlighting age-related changes in oocyte quality.
Related Concept Videos
02:07Oogenesis
In human women, oogenesis produces one mature egg cell or ovum for every precursor cell that enters meiosis. This process differs in two unique ways from the equivalent procedure of spermatogenesis in males. First, meiotic divisions during oogenesis are asymmetric, meaning that a large oocyte (containing most of the cytoplasm) and minor polar body are produced as a result of meiosis I, and again following meiosis II. Since only oocytes will go on to form embryos if fertilized, this unequal...
01:22Oogenesis
Oogenesis, the process of developing egg cells (female gametes), occurs within the ovaries and is fundamental to female fertility. This sequence begins during fetal development when diploid oogonia in the developing ovaries undergo mitotic divisions to produce primary oocytes. By birth, these primary oocytes enter prophase I of meiosis but become arrested in this stage, remaining suspended until puberty.
Each primary oocyte is surrounded by a layer of pre-granulosa cells, forming what is known...
Each primary oocyte is surrounded by a layer of pre-granulosa cells, forming what is known...
01:28Menopause
Menopause, a natural biological process marking the end of a woman's fertility, typically occurs between the fifth and sixth decade of life. This phase is characterized by the exhaustion of the ovarian follicle pool, leading to less responsive ovaries despite the high levels of Follicle Stimulating Hormone (FSH) and Luteinizing Hormone (LH). The consequential decrease in estrogen production results in symptoms like hot flashes, heavy sweating, headaches, hair loss, muscle pains, vaginal...
01:29Bone Disorders
Aging and its effect on bone remodeling is the most common cause of bone disorders. In young and healthy people, bone deposition and resorption happen at an equal rate to maintain optimal bone health.
Bone deposition is also affected by the levels of sex hormones like estrogen and testosterone that promote osteoblast activity and bone matrix synthesis. When the level of these hormones decreases due to aging, it causes a reduction in bone deposition. As a result, bone resorption by osteoclasts...
Bone deposition is also affected by the levels of sex hormones like estrogen and testosterone that promote osteoblast activity and bone matrix synthesis. When the level of these hormones decreases due to aging, it causes a reduction in bone deposition. As a result, bone resorption by osteoclasts...
01:30Hormonal Control of the Ovarian Cycle
The ovarian cycle is meticulously regulated by the hypothalamic-pituitary-gonadal axis. This cycle orchestrates the release of a mature oocyte, essential for reproduction.
Before puberty, the hypothalamus releases GnRH in a low frequency, low amplitude pulsatile manner. This along with the immature hypothalamic-pituitary-gonadal axis activity, results in low estrogen levels and the absence of a fully functional ovarian cycle. At puberty, GnRH secretion increases in both frequency and...
Before puberty, the hypothalamus releases GnRH in a low frequency, low amplitude pulsatile manner. This along with the immature hypothalamic-pituitary-gonadal axis activity, results in low estrogen levels and the absence of a fully functional ovarian cycle. At puberty, GnRH secretion increases in both frequency and...