Stable serum levels of relaxin throughout the menstrual cycle: a preliminary comparison of women with premenstrual dysphoria and controls

Abstract

Serum levels of relaxin in 25 women with premenstrual dysphoria and 25 age-matched controls were determined at three time points during the menstrual cycle. At the same time, levels of estradiol, progesterone, 17-beta-OH-progesterone, free testosterone, total testosterone, sex hormone binding hormone, androstenedione, dehydroepiandrosterone sulphate, and 3-alpha-androstanediol glucuronide were determined. Detectable levels of relaxin were found in all women in both the follicular and luteal phase as well as around ovulation, the inter-individual variations being larger than intra-individual differences. The levels of relaxin were not influenced by the fluctuation of the other reproductive hormones. A significant difference between the two groups of women was observed, subjects with premenstrual dysphoria displaying reduced levels of relaxin (p < 0.05) compared to controls. Also, when analysed with respect to a variable number of tandem repeats polymorphism (CT repeats followed by GT repeats) in the promotor region of the relaxin H2 gene, women with premenstrual dysphoria (n = 29) were found to display significantly longer GT repeats than controls (n = 35).

Trends in serum relaxin concentration among elite collegiate female athletes

“…The SRCs among our athletes were also lower than those reported by Stewart13 among women with nonconceptive cycles (30–150 pg/mL). Additionally, these SRCs were lower than those reported among older parous women by Binder et al (260–620 pg/mL, Santa Cruz Biotechnology Inc. assay),23 by Pehrrson et al (144–4500 pg/mL, Immunodiagnostix assay),22 and by Wreje et al (20–255 ng/L, Genentech reagents) 34. Just as all these studies reported 1 to several participants with unexpectedly high SRCs, our study also revealed outliers.…”

“…However, the majority of previously used assays do not report their level of specificity or cross-reactivity profiles. Only a couple have reported having no cross reactivity with insulin,22,23 or IGF-1 23. Lastly, this difference could also reflect a sustained increase in SRC among primi- or multiparous women, which makes their SRCs significantly higher than those of nulligravidae women.…”

“…Because of its well-established role as a female reproductive hormone, the collagenolytic effects of Relaxin-2 have been studied primarily with respect to its effect on pregnancy and parturition,18,19 myometrial pathology,20 urinary incontinence,21 and premenstrual dysphoric disorder22 in middle-aged women. More recently, a number of studies have begun to investigate the role of relaxin in nonreproductive organ and tissue disease processes 23–26…”

Update on Research and Treatment of Premenstrual Dysphoric Disorder

“…105 Differences in levels of relaxin—a reproduction-related peptide (e.g., in pregnancy-associated changes in the cervix and pubic symphysis)—also were reported, although levels were not linked to symptom expression. 106 …”

ACL Research Retreat VII: An Update on Anterior Cruciate Ligament Injury Risk Factor Identification, Screening, and Prevention

“…Because relaxin rises and peaks during a relatively short window (6-10 days) after ovulation based on other hormonal events, [217][218][219][220] we do not know if the high proportion of undetectable levels within a single sample (as high as 64%-80%) [221][222][223][224] is due to timing or suggests that only a subset of females are exposed to appreciable relaxin levels due to mediating factors. 219,221,225 5. Because cyclic hormone concentrations affect soft tissues and knee-joint function, studies comparing females with males should be made during the early follicular phase in females, when hormone levels are at their nadirs (preferably 3-7 days postmenses).…”