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Updated: Jun 25, 2026

Collection of Human Follicular Fluid, Follicle Somatic Cells, and Immature Oocytes from Individuals Undergoing In Vitro Fertilization
Published on: October 24, 2025
Age-related variations in follicular apolipoproteins may influence human oocyte maturation and fertility potential
Tiffany Von Wald1, Yevgeniya Monisova, Michele R Hacker
1Department of Obstetrics and Gynecology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA.
Objective:
To investigate involvement of specific apolipoproteins in the process of human oocyte maturation and age-related infertility as molecular constituents of follicular fluid.
Design:
Laboratory-based observational study.
Setting:
Basic science laboratory at a large academic institution.
Patient(S):
Follicular fluid obtained from healthy women aged 18 to 45 years undergoing in vitro fertilization for unexplained infertility, ovulatory dysfunction, tubal disease, male factor infertility, or oocyte donation.
Intervention(S):
None.
Main Outcome Measure(S):
Specific concentration of apolipoproteins and content of lipoprotein particles in follicular fluid and blood plasma as related to reproductive aging.
Result(S):
We registered a decline of follicular apolipoprotein A1 (Apo A1) and apolipoprotein CII (Apo CII) and an increase of the apolipoprotein E (Apo E) with age, which parallels a lower number of retrieved mature oocytes in older women. Follicular apolipoprotein A1, apolipoprotein B (Apo B), apolipoprotein E, and apolipoprotein C II are present in diverse heterogeneous complexes including very-low-density lipoproteins (VLDL), intermediate-low-density lipoproteins (IDL), low-density lipoproteins (LDL), and high-density lipoproteins (HDL) that vary with patient age and differ from the blood plasma lipoprotein complexes.
Conclusion(S):
Age-related variation in follicular apolipoprotein content and distribution in the cholesterol particles may be associated with the decrease in production of mature oocytes and the age-related decline in fertility potential.
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