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Updated: Jul 6, 2026

Doppler Ultrasonography for Live Imaging and Quantification of Ovarian Vascular Function in Mice
Published on: November 14, 2025
Excessive ovarian response is associated with increased expression of interleukin-2 in the periimplantation
Guneet Makkar1, Ernest Hung Yu Ng, William Shu Biu Yeung
1Department of Obstetrics and Gynecology, The University of Hong Kong, Hong Kong, People's Republic of China.
Objective:
To evaluate and compare in vivo expression of T helper type 1 (Th1) cytokines in the peri-implantation endometrium of infertile patients between natural and stimulated cycles.
Design:
An observational study.
Setting:
A tertiary assisted reproduction center.
Patient(S):
Infertile patients.
Intervention(S):
Uterine flushings and endometrial biopsies were collected 7 days after LH surge in natural cycles or after hCG injection in stimulated cycles.
Main Outcome Measure(S):
T helper type 1 cytokines were determined by immunolocalization and by ELISA.
Result(S):
Natural cycles were classified as group A (n = 17), whereas stimulated cycles with peak serum E(2) of
Conclusion(S):
Increased expression of IL-2 in the peri-implantation endometrium may account for the lower implantation rate in excessive responders.
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