Obesity Effects on Oocyte Quality and Ovarian Function

Obesity disrupts ovarian physiology at multiple levels, compromising both the microenvironment of the follicle and the intrinsic competence of the oocyte. Excess adiposity drives systemic insulin resistance, chronic inflammation and altered adipokine signalling, which in turn perturb granulosa and theca cell function. Lipid overload and lipotoxic intermediates accumulate within the follicular fluid, inducing oxidative stress and mitochondrial dysfunction in oocytes. These stressors undermine key processes such as meiotic spindle assembly, mitochondrial membrane potential maintenance and cytoplasmic maturation. At the molecular level, obesity modifies DNA methylation landscapes and histone marks within oocytes, with potential intergenerational consequences. The combined effect is reduced oocyte developmental competence, impaired fertilisation, delayed embryonic progression and increased rates of miscarriage. Globally, as rates of obesity rise, these changes carry significant implications for natural fertility and outcomes of assisted reproductive technologies. Strategies to restore ovarian resilience include lifestyle modification, targeted antioxidant therapies and modulation of metabolic sensors to safeguard oocyte quality and preserve female reproductive potential.

Research from Nature Portfolio

Recent studies have demonstrated in mouse models that both diet-induced and genetic forms of obesity perturb oocyte maturation and mitochondrial integrity. One foundational investigation showed that high-fat feeding and leptin deficiency independently disrupted spindle morphology, elevated reactive oxygen species and triggered early oocyte apoptosis, while also altering DNA and histone methylation patterns. A complementary analysis compared inbred and outbred strains under a high-fat regimen, revealing strain-dependent differences in mitochondrial membrane potential, ultrastructural abnormalities and endoplasmic reticulum interactions. These findings highlight mitochondrial dysfunction as a central mechanism by which obesity impairs oocyte quality, and they caution against uncritical extrapolation between genetic models when considering human applications.

Obesity Effects on Oocyte Quality and Ovarian Function publication trend

The graph below shows the total number of articles in obesity effects on oocyte quality and ovarian function across all publications each year (not limited to Nature Index journals).

Technical terms

Oocyte: The female gamete or egg cell, central to fertilisation and early embryonic development.

Steroidogenesis: Biosynthetic pathway in ovarian follicles that produces oestrogens and progesterone.

Mitochondrial homeostasis: Balance of mitochondrial dynamics (fusion, fission), biogenesis and function essential for oocyte energy supply.

Oxidative stress: Imbalance between reactive oxygen species production and antioxidant defence, leading to cellular damage.

Nodal signalling: A transforming growth factor-β family pathway that regulates follicular cell function and steroidogenic gene expression.

AMPKα: A cellular energy sensor that governs mitochondrial fission through phosphorylation of mitochondrial fission factor (MFF).

References

1. High-fat diet-induced L-saccharopine accumulation inhibits estradiol synthesis and damages oocyte quality by disturbing mitochondrial homeostasis. Gut Microbes (2024).
2. Increased susceptibility to diet-induced obesity in female mice impairs ovarian steroidogenesis: The role of elevated leptin signalling on nodal activity inhibition in theca cells. Molecular Metabolism (2024).
3. High-fat diet-negative impact on female fertility: from mechanisms to protective actions of antioxidant matrices. Frontiers in Nutrition (2024).
4. Both diet and gene mutation induced obesity affect oocyte quality in mice. Scientific Reports (2016).
5. Differential effects of high fat diet-induced obesity on oocyte mitochondrial functions in inbred and outbred mice. Scientific Reports (2020).