Oligomenorrhea study finds mood and sleep differences that fall short of significance

Women whose menstrual cycles stretch beyond 35 days reported higher levels of depressive symptoms and poorer sleep on average than women with regular cycles, according to a comparative study published in the Bulletin of Faculty of Physical Therapy. Yet when the researchers subjected those differences to formal statistical testing, the gaps between the two groups did not reach significance, a nuance that shapes how the findings should be read.

The study, led by Uzma Sheerin and colleagues, enrolled 100 females divided equally into two groups: 50 with oligomenorrhea, a menstrual disturbance in which intervals between periods exceed 35 days, and 50 with normal menstrual cycles. Participants were recruited from Majeedia Hospital, Jamia Hamdard, and Al-Shifa Hospital in Delhi using convenience sampling. To qualify, women had to be between 15 and 35 years old, and those in the oligomenorrhea group needed a clinical diagnosis confirmed by a gynecologist for at least the previous six months. Anyone with a history of psychological disorders, uncontrolled hormonal or endocrine conditions such as endometriosis, fibroids, thyroid dysfunction or PCOD, or an eating disorder was excluded.

Each participant completed a structured form with three sections: demographic details, the Pittsburgh Sleep Quality Index, and the Hamilton Depression Rating Scale. The PSQI assessed sleep quality over the past month, while the HDRS-17 measured depression severity over the past week. The PSQI contains 19 items, of which nine contribute to scoring across seven components rated from 0 for no difficulty to 3 for severe difficulty. The global score ranges from 0 to 21, with values above 5 signifying poor sleep. The HDRS-17 uses 17 items, most scored from 0 to 4, producing totals up to 52 that are classified into bands from normal through mild, moderate, severe and very severe depression.

The sample had a mean age of 23.02 years with a standard deviation of 4.50, and a mean body mass index of 23.07 with a standard deviation of 4.18. In the oligomenorrhea group, the mean HDRS score was 15.00, a value the authors describe as reflecting mild to moderate depression, whereas the control group averaged 0.94, suggesting minimal depressive symptoms. The oligomenorrhea group also recorded a global PSQI score of 10.8 against 5.74 in the control group, alongside higher mean sleep latency, disturbance and daytime dysfunction and lower sleep efficiency.

When the two groups were compared with independent-samples t-tests, however, none of these differences crossed the threshold for statistical significance. The analysis reported no significant differences for BMI, HDRS score, subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbance, sleep medication use, daytime dysfunction, or the global PSQI score. Sleep medication use did not differ significantly between the groups, which the authors suggest may reflect limited awareness, access, or a preference for non-pharmacological sleep strategies among young females. BMI likewise did not differ significantly, and because the average BMI of both groups sat within the normal range, the authors note that its influence on menstrual irregularities and sleep outcomes may have been limited in this sample.

The authors interpret the pattern of higher means cautiously. Although participants with oligomenorrhea demonstrated higher mean HDRS and PSQI scores than those with normal cycles, the differences were not statistically significant in the present analysis, and similar trends appeared across the individual PSQI components. The study therefore suggests a tendency toward poorer emotional well-being and sleep quality among women with oligomenorrhea, while stressing that the observed differences should be interpreted carefully because statistical significance was not achieved. The researchers call for further studies with larger sample sizes and objective sleep assessments to better understand the relationship between oligomenorrhea, psychological health, and sleep quality.

The biological backdrop the authors outline helps explain why such a link is plausible. The menstrual cycle is regulated by the hypothalamic-pituitary-ovarian axis: the hypothalamus releases gonadotropin-releasing hormone in a balanced pulsatile pattern, prompting the pituitary to secrete follicle-stimulating hormone and luteinizing hormone. FSH supports the growth of ovarian follicles while LH triggers ovulation, and the ovaries then produce estrogen and progesterone, which regulate the uterine lining and feed back to the hypothalamus and pituitary to maintain cycle rhythm. In oligomenorrhea, this rhythm is disturbed: GnRH frequency becomes abnormally high, favoring excessive LH secretion over FSH, and the elevated LH-to-FSH ratio promotes androgen production from ovarian theca cells. High androgens interfere with follicular maturation, ovulation often fails, progesterone production drops, and cycles lengthen beyond 35 days. Oligomenorrhea is often linked to polycystic ovary syndrome.

Hormonal fluctuations of this kind are also entangled with sleep and mood. The authors note that sleep quality is closely associated with menstrual regularity, because hormonal fluctuations influence circadian rhythms and sleep disturbances can in turn disrupt reproductive hormone production. Estrogen has been shown to enhance serotonergic activity, promoting sleep onset, whereas low progesterone levels may impair GABAergic inhibition, leading to increased arousal and fragmented sleep. Estrogen and progesterone also influence neurotransmitters crucial in modulating sleep and mood. Globally, menstrual disturbances including dysmenorrhea, oligomenorrhea, amenorrhea, premenstrual syndrome and polycystic ovary syndrome affect approximately 30 to 40 percent of women, making the search for their psychological correlates a matter of scale as well as mechanism.

The study’s own limitations temper its conclusions. It focused only on subjects with oligomenorrhea, and the authors note that including participants with other menstrual dysfunctions could have provided broader comparative insights. Sleep quality was assessed solely with the PSQI questionnaire, and the authors suggest that objective measures such as electroencephalography could have enhanced the accuracy of sleep evaluation. The sample was recruited by convenience sampling from two Delhi hospitals, and the sample size was calculated using G*Power with Cohen’s d of 0.60, an alpha of 0.05, 80 percent power and a 1:1 allocation ratio. Data were analyzed in SPSS version 21, with descriptive statistics expressed as mean plus or minus standard deviation and a two-tailed significance level of 0.05.

For readers weighing what this study means, the honest summary is a study of tendencies rather than confirmed differences. Among 100 young women in Delhi, those with oligomenorrhea scored higher on average for depressive symptoms and poorer sleep across nearly every measured domain, and the authors argue that the findings underscore the interplay between menstrual irregularities, mood disturbances and sleep impairment, suggesting that addressing hypothalamic-pituitary-ovarian axis dysfunction may be crucial for improving psychological and sleep outcomes. But the formal tests did not confirm those gaps as statistically significant, BMI showed no association, and the authors themselves recommend larger samples and objective sleep measurement before firmer conclusions are drawn. The value of the work lies in its careful mapping of a hypothesis worth testing at scale, not in a proven link between irregular cycles and the mood and sleep problems that so often accompany them.

Subject of Research: A comparative observational study of oligomenorrhea, BMI, mood disturbances and sleep quality in young women

Article Title: Relationship between oligomenorrhea, BMI, mood disturbances, and sleep quality: an observational perspective

Article References: Sheerin, U., Aman, I., Zutshi, K., Saifi, S., Khan, H., & Asif, M. (2026). Relationship between oligomenorrhea, BMI, mood disturbances, and sleep quality: an observational perspective. Bulletin of Faculty of Physical Therapy, 31(1), Article 31. https://doi.org/10.1186/s43161-026-00367-6

Image Credits: AI Generated

DOI: 10.1186/s43161-026-00367-6

Keywords: oligomenorrhea, menstrual cycle, sleep quality, depression, BMI, PSQI, HDRS-17, HPO axis, reproductive health, women's health, observational study, Relationship