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Updated: May 2, 2026

Collection of Human Follicular Fluid, Follicle Somatic Cells, and Immature Oocytes from Individuals Undergoing In Vitro Fertilization
Published on: October 24, 2025
[Correlation of follicular fluid human chorionic gonadotrophin level with oocyte maturity and early embryonic
Lili Zhang1, Haiying Wang, Renli Zhang
1Southern Medical University, Guangzhou 510515, China.E-mail: 83617673@qq.com.
Objective:
To explore the correlation of human chorionic gonadotrophin (hCG) level in the follicular fluid on oocyte retrieval day with the number of oocytes retrieved, maturation rate, embryonic development, and pregnancy outcome in controlled ovarian stimulation cycles.
Methods:
The data of 311 IVF/ICSI-ET cycles from 2012 to 2013 was analyzed and stratified according to hCG level in follicular fluid on oocyte retrieval day (<7 nmol/L, 7-14 nmol/L, 14-21 nmol/L, and >21 nmol/L) determined with chemiluminescence method. The number of oocytes retrieved, oocyte maturation rate, fertilization rate, cleavage rate, available embryo rate and pregnancy rate were compared between the groups.
Results:
In the IVF/ICSI-ET cycles, the cycles with hCG level of 14-21 nmol/L in the follicular fluid on the day of oocyte retrieval had significantly higher oocyte maturation rate and fertilization rate than those in the other 3 groups (P<0.05), but the number of oocytes retrieved, cleavage rate, available embryo rate and pregnancy rate, though slightly higher, showed no significant difference from the other 3 groups (P>0.05). In the group with hCG level >21 nmol/L, the oocyte maturation rate and fertilization rate were significantly lower than those in the other 3 groups (P<0.05), and the available embryo rate and pregnancy rate were slightly lower without significant differences from the other 3 groups (P<0.05).
Conclusion:
Follicular fluid hCG level on the day of oocyte retrieval is associated with oocyte maturation, fertilization, embryonic development potential, and IVF outcome. An excessively high follicular fluid hCG level on the day of oocyte retrieval may have negative effects on oocyte maturation and embryo development.
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