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Updated: Aug 21, 2026
Whole Ovary Immunofluorescence, Clearing, and Multiphoton Microscopy for Quantitative 3D Analysis of the Developing Ovarian Reserve in Mouse
Published on: September 3, 2021
Gonadotrophin dynamics during reproductive life
S F de Medeiros1, P E Assi, M M W Y de Medeiros
1Human Reproductive Unit, Júlio Muller University Hospital, Brazil.
Objective:
To evaluate the follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels in early follicular phase throughout the reproductive years.
Method:
FSH and LH concentrations were determined by radioimmunoassay (RIA). Linear and polynomial regressions were carried out considering basal FSH as the dependent and age as the independent variable.
Results:
FSH levels increased throughout the reproductive years (P<0.025). A positive correlation between age and basal FSH levels was detected (P<0.05). The Pearson squared coefficient of r(2)=0.889 was obtained. Using polynomial regression, the inclination of the parabole (Y=7.97-0.009x+0.057x(2)) was 0.359 and the generalized correlation coefficient was r=0.795. The goodness of fit analysis showed that the parabole may better represent the phenomenon (F=4.7; P<0.05). The LH levels remained constant, increasing only beyond 40 years of age.
Conclusion:
The FSH levels rose in a nonlinear way during the reproductive life and the LH concentrations increased discreetly only in patients over 40 years of age.
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