Endometrial development during the transition to menopause: preliminary associations with follicular dynamics

Abstract

Objective: This study aimed to test the hypothesis that the development of functional luteal phase dominant follicles (LPDFs) is associated with increased endometrial growth as women transition to menopause.

Methods: Endometrial thickness (ET), follicle development, and hormone production were characterized in ovulatory women of mid-reproductive age (MRA; 18–35 years, n = 10) and advanced reproductive age (ARA; 45–55 years, n = 16). Transvaginal ultrasonography was conducted every 1–3 days during one interovulatory interval to quantify ET and the diameters of follicles ≥2 mm. Blood was drawn at each visit to measure progesterone, estradiol, inhibin A, follicle stimulating hormone, and luteinizing hormone.

Results: In the MRA group, ET was lower (8.87 vs. 10.1 mm) in women with typical versus no LPDFs, in association with greater luteal phase estradiol (91.1 vs. 48.8 ng/l). In the ARA group, luteal phase endometrial growth was greater (12.0 vs. 10.4 mm) in women with typical versus no LPDFs, in association with lower progesterone (10.7 vs. 13.8 μg/l; LPDF effect p < 0.1) and inhibin A (35.6 vs. 51.17 ng/l; p < 0.10).

Conclusions: Preliminary findings suggest that ET may be increased in women who develop LPDFs, in association with reduced luteal phase progesterone and inhibin A, during the transition to menopause. Continued research is required to confirm these findings.

摘要

目的：本研究旨在探究功能性黄体期优势卵泡（LPDFs）的发育与女性绝经过渡期子宫内膜生长增加相关性的假说。

方法：子宫内膜厚度（ET）、卵泡发育和激素产生是对生育年龄中期（MRA;18-35岁, n=10)和生育年龄晚期（ARA;45-55岁, n=16）女性, 处于排卵期的特征。在一个排卵周期内, 每1-3天进行一次经阴道超声检查, 以量化ET和直径≥2mm的卵泡。每次访视均抽血测定黄体酮、雌二醇、抑制素A、卵泡刺激素和黄体生成素。

结果：在MRA组中, 典型患者与无LPDFs患者相比, ET较低（8.87vs10.1mm）, 而黄体期雌二醇水平更高（91.1vs.48ng/l）。在ARA组, 典型患者与无LPDFs患者相比黄体期子宫内膜生长较好（12.0vs.10.4mm）, 黄体酮（10.7vs13.8lg/l; LPDF影响p<0.1）和抑制素A（35.6vs.51.17ng/l;p<0.10）较低。

结论：初步研究表明, 在绝经过渡期间, LPDFs患者体内的ET水平可能会随着黄体酮和抑制素A的减少而升高。需要继续深入研究来证实这些发现。

Keywords:

• Age
• endometrium
• estradiol
• follicle
• inhibin A
• menopause
• progesterone
• ovary

Acknowledgements

The authors would like to thank the research volunteers, whose participation was invaluable for the conduct of this study. The authors would also like to thank Dr Roger Pierson at the University of Saskatchewan, Canada for assistance with facilitating data collection and Dr David Robertson at the Hudson Institute of Medical Research, Australia for assistance with data interpretation in this study.

Potential conflict of interest

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the National Health and Medical Research Council, Canadian Institutes of Health Research – Banting and Best Graduate Training Award, Canadian Foundation for Women's Health, Victorian Government's Operational Infrastructure Support Program and the University of Saskatchewan, Establishment Grant.