Variability in the Assessment of Reproductive Hormone Levels During a Day

[Nelson Vergel]

Fertil Steril. 2023 Nov 15:S0015-0282(23)01999-4. doi: 10.1016/j.fertnstert.2023.11.010. Online ahead of print.

Quantifying the Variability in the Assessment of Reproductive Hormone levels

Ali Abbara 1, Sophie Adams 2, Maria Phylactou 1, Chioma Izzi-Engbeaya 1, Edouard G Mills 1, Layla Thurston 1, Kanyada Koysombat 1, Simon Hanassab 3, Thomas Heinis 4, Tricia M-M Tan 5, Krasimira Tsaneva-Atanasova 6, Alexander N Comninos 1, Margaritis Voliotis 6, Waljit S Dhillo 7


Abstract
Objective: To quantify how representative a single measure of reproductive hormone is of the daily hormonal profile using data from detailed hormonal sampling in the saline placebo-treated arm conducted over several hours.

Design: Retrospective analysis of data from previous interventional research studies evaluating reproductive hormones.

Subjects: Overall, 266 individuals including healthy men and women (n=142), and those with reproductive disorders/states (n=124) [11 with functional hypothalamic amenorrhoea (FHA), 6 with polycystic ovary syndrome (PCOS), 62 women and 32 men with hypoactive sexual desire disorder (HSDD), and 13 post-menopausal women] were included in the analysis.

Interventions: Data from 266 individuals who had undergone detailed hormonal sampling in the saline placebo-treated arms of previous research studies was used to quantify the variability in reproductive hormones due to pulsatile secretion, diurnal variation, and feeding using coefficient of variation (CV) and entropy.

Main outcome measures: The ability of a single measure of reproductive hormone to quantify the variability in reproductive hormones due to pulsatile secretion, diurnal variation, and nutrient-intake.

Results: The initial morning value of reproductive hormones was typically higher than the mean value throughout the day (percentage decrease from initial morning measure to daily mean: LH 18.4%, FSH 9.7%, testosterone 9.2%, and estradiol 2.1%). LH was the most variable (CV 28%), followed by sex-steroids (testosterone 12%, estradiol 13%), whereas FSH was the least variable reproductive hormone (CV 8%). In healthy men, testosterone fell between 9am and 5pm by 14.9% (95% CI 4.2, 25.5%), although morning levels correlated with (and could be predicted from) late afternoon levels in the same individual (r2=0.53, p<0.0001). Testosterone was reduced more after a mixed meal (by 34.3%) than during ad libitum feeding (9.5%), or after an oral glucose load (6.0%), or an intravenous glucose load (7.4%).

Conclusion: Quantification of the variability of a single measure of reproductive hormones informs the reliability of reproductive hormone assessment.

Keywords: diurnal; feeding; hypogonadism; reproductive hormones; variability.

 

[Nelson Vergel]

Understanding Variability in Measuring Reproductive Hormones​

Overview​

Objective: The aim was to determine how accurately a single hormone test reflects the daily hormonal changes in the body. This was done by examining data from detailed hormone tests conducted over several hours on individuals who received a saline placebo.

Study Design​

This was a retrospective study, meaning it looked back at data from previous studies that focused on reproductive hormones.

Participants​

The study included 266 participants:

• 142 healthy men and women
• 124 individuals with reproductive health issues, including:
  • 11 with functional hypothalamic amenorrhea (FHA), a condition where menstrual periods stop due to stress or weight loss
  • 6 with polycystic ovary syndrome (PCOS)
  • 62 women and 32 men with hypoactive sexual desire disorder (HSDD)
  • 13 post-menopausal women

Method​

The researchers used data from these individuals who had undergone detailed hormone tests. They analyzed the variations in hormone levels due to natural fluctuations throughout the day, changes caused by eating, and other factors. They used statistical methods like the coefficient of variation (CV) and entropy to measure these variations.

Key Findings​

• Morning levels of reproductive hormones were generally higher than the average levels during the day.
• The hormone luteinizing hormone (LH) showed the most variation, followed by sex hormones like testosterone and estradiol. Follicle-stimulating hormone (FSH) had the least variation.
• In healthy men, testosterone levels decreased from morning to evening by about 15%.
• Testosterone levels changed more significantly after a regular meal compared to fasting or consuming glucose.

Conclusion​

This study helps understand how reliable a single hormone test is in assessing reproductive hormone levels, considering the natural variability in these hormones.

Key Terms​

• Diurnal: Related to daily cycles
• Feeding: The impact of eating on hormone levels
• Hypogonadism: A condition where the body doesn't produce enough sex hormones
• Reproductive hormones: Hormones that play a role in sexual function and reproduction
• Variability: The degree to which these hormone levels fluctuate