Menstruation Research Activities and Advances

The following organizational units address issues related to menstruation and the causes and effects of menstrual irregularities:

• The Division of Population Health Research (DiPHR) is interested in statistical methodology, comparative etiologies, and the health endpoints needed to identify mechanisms, at-risk groups, and interventions. Some of these activities include:
  • Gaining a better understanding of the intricate relationship between hormone levels (estrogen, progesterone, luteinizing hormone, etc.) and oxidative stress during the menstrual cycle. Oxidative stress may be associated with the risk of infertility in both males and females. Data from the BioCycle Study are helping researchers examine the intracycle variation of oxidative stress, reproductive hormones, inflammation, and metabolic biomarkers; the relation between hormone levels and oxidative stress during the menstrual cycle in premenopausal women; and the influence of external factors (such as dietary intake, cigarette smoking, alcohol consumption, and exercise) on oxidative stress and hormone levels.
  • Developing various approaches to modeling menstrual cycle function. The menstrual cycle is a complex process that involves multiple hormones regulated by feedback mechanisms. To describe the factors associated with menstrual cycle function and inform women's health research, the DIPHR is developing statistical models to answer questions like:
    • What is the "typical" menstrual cycle pattern in a population of women?
    • How do lifestyle factors that vary between women (e.g., dietary intake, physical activity, stress) affect a typical menstrual cycle?
    • How does the variation in menstrual cycle function differ between women and across consecutive cycles on the same woman?
    • What is the inter-relationship between multiple hormones across the menstrual cycle?
  • Determining the relationships between endometriosis and environmental chemicals, lifestyle, and medical history. The Endometriosis: Natural History, Diagnosis, and Outcomes (ENDO) Study is following 625 women undergoing surgery for this disorder, which often involves irregular, painful menstruation. The study compares these women's medical findings, life characteristics, and other factors to those of women of similar age and location who don't have endometriosis.
• Various components of the Division of Intramural Research study aspects of menstruation and menstrual irregularities. For example:
  • The Section on Reproductive Endocrinology works on endometrial physiology and endometriosis pathologies. The section has published studies on the endometrium, localization of lesions in endometriosis, characterizing receptors, and the use of raloxifene as a treatment for endometriosis. This section also published a landmark article on the hypothalamic-pituitary-adrenal (HPA) axis during pregnancy.
  • The Unit on Reproductive and Regenerative Medicine conducts research on disorders that affect reproduction. The section is interested in endometrial stem cells and disorders that affect the endometrium. These disorders can result in scarring of the uterine cavity, abnormal bleeding, endometriosis, infertility due to implantation failures, and recurrent pregnancy loss.
  • The Unit on Reproductive Endocrinology and Infertility is studying the relationship between the BRX gene complex and uterine fibroid generation. The laboratory also is studying gene regulation and growth factors involved in uterine fibroid development.
  • The Unit on Genetics of Puberty and Reproduction conducts research on the genetic basis of sexual maturation. In particular, researchers are examining the ways in which mutations in genes linked to pubertal development can lead to disorders of puberty and reproduction.
• Components of the Division of Extramural Research also support studies on normal menstruation and conditions related to menstrual irregularities.
  • Fertility and Infertility (FI) Branch projects include work examining hormonal and neuroendocrine control of normal menstrual cycling, which can help provide insights into conditions where these normal processes are disrupted.
  • A Pediatric Growth and Nutrition Branch project is investigating the relationship of amenorrhea to bone loss in adolescent and young adult athletes by examining the bone metabolism and body composition of young athletes.
  • The Gynecologic Health and Disease Branch (GHDB) studies normal menstruation as well as diseases that cause menstrual irregularities, such as uterine fibroids, endometriosis, and polycystic ovary syndrome, to name a few. Projects include:
    • Central pain mechanisms in primary dysmenorrhea: This project will examine how the nervous system and psychological factors play a role in the experience of dysmenorrhea.
    • Neurophysiological diagnostics for menstrual pain: This study aims to determine whether involuntary muscle movements/reflexes (called visceral motor reflexes or VMRs) can be measured to evaluate the pain experienced by women with different types of pelvic pain. The study will compare these VMRs in women with primary dysmenorrhea and women with chronic pelvic pain to determine which nerve pathways are responsible for the pain experienced and to potentially identify targets for treatment.

• The Uterine Fibroids and Women’s Health fact sheet describes NICHD research on uterine fibroids and women's health, and reviews recent advances in understanding, diagnosing, and treating them.
• The Polycystic Ovary Syndrome (PCOS) and Women's Health fact sheet describes NICHD research on PCOS and women's health. It highlights recent projects and findings related to PCOS causes, symptoms, and treatments.
• The Endometriosis and Women’s Health fact sheet describes NICHD’s support of research on this common gynecologic condition and highlights some recent findings and advances from NICHD-funded projects.
• Through the FI Branch, NICHD supports the following research networks and centers programs that contribute to understanding menstrual irregularities within the context of fertility and infertility:
  • Reproductive Medicine Network (RMN)
  • Reproductive Scientist Development Program (RSDP)
  • National Centers for Translational Research in Reproduction and Infertility (NCTRI) (Formerly the Specialized Cooperative Centers Program in Reproduction and Infertility Research [SCCPIR])
• The GHDB supports the Women's Reproductive Health Research (WRHR) Career Development Program, which allows obstetricians/gynecologists who have recently completed clinical training to enhance their education and experience with basic, translational, and clinical research on women's health topics, including normal menstruation and menstrual irregularities.