The DOI matches its Crossref record; 12 of the 12 references it cites were found in a registry or an index.
The Length and Variability of the Human Menstrual Cycle
Abstract
The Center for Population Research collected 30,655 recorded menstrual cycles from 2,316 women. Ninety-five percent of all cycles were between 15 and 45 days long. The mean and standard deviations for the total number of cycles were 29.1 and 7.46, respectively. Cycle lengths between 15 and 45 days averaged 28.1 days with a standard deviation of 3.95 days. Variability of menstrual-cycle lengths is highest for women under 25 years of age and declines steadily to reach a minimum for ages 35 to 39. It is then followed by a slight increase for women aged 40 to 44. The pattern of variability by age is demonstrated equally well by the percent of cycles between 25 and 31 days in length as by the standard deviation.
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In the citing paper
“Although the average length of a woman’s menstrual cycle is 28 days, there is considerable intra- and inter-individual variation in cycle lengths as well as changes in a woman’s own personal cycle with time (Treloar et al. 1967; Chiazze et al. 1968; Vollman 1977; Münster et al. 1992; Park et al. 2007; Johnson et al. 2009).”
From Real-life insights on menstrual cycles and ovulation using big data (2020) · cites this paper as Chiazze et al. 1968
In the citing paper
“These results are in alignment with those of reference studies.3,6,9”
From Real-world menstrual cycle characteristics of more than 600,000 menstrual cycles (2019) · cites this paper as [9]
In the citing paper
“With increasing age, cycle length reduces and the timing of ovulation becomes earlier; the variation of a woman’s cycle length reduces with age until menopause.5,6,8,9”
From Real-world menstrual cycle characteristics of more than 600,000 menstrual cycles (2019) · cites this paper as [9]
In the citing paper
“The day of ovulation varies on an inter- and intra-individual level.”
From Real-life insights on menstrual cycles and ovulation using big data (2020) · cites this paper as Chiazze et al. 1968
In the citing paper
“The cycle characteristics described in this study are consistent with previous findings on research cohorts (Chiazze et al. 1968; Vollman 1977; Münster et al. 1992; Johnson et al. 2009; 2018), indicating that previous clinical findings are still reflective of cycle characteristics of today’s population of women who are seeking to conceive.”
From Real-life insights on menstrual cycles and ovulation using big data (2020) · cites this paper as Chiazze et al. 1968
Citations
Cites
VARIATION OF THE HUMAN MENSTRUAL CYCLE THROUGH REPRODUCTIVE LIFE
TRELOAR, A. E., BOYNTON, R. E., BEHN, B. G., & BROWN, B. W. (1968) · Obstetrical & Gynecological Survey · doi:10.1097/00006254-196801000-00019 · Cited by 1,018
The Degree of Normal Menstrual Irregularity
Arey, L. B. (1939) · American Journal of Obstetrics and Gynecology · doi:10.1016/s0002-9378(16)40957-9 · Cited by 82
The Effect of Age upon the Pattern of the Menstrual Cycle
Collett, M. E., Wertenberger, G. E., & FISKE, V. M. (1954) · Fertility and Sterility · doi:10.1016/s0015-0282(16)31742-3 · Cited by 81
Statistical studies on menstruation;a criticism on the definition of normal menstruation.
Matsumoto, S. (1962) · Gunma Journal of Medical Sciences · Cited by 80
Menstrual Periodicity; Statistical Observations on a Large Sample of Normal Cases
Gunn, D. L., Jenkin, P. M., & Gunn, A. L. (1937) · BJOG An International Journal of Obstetrics & Gynaecology · doi:10.1111/j.1471-0528.1937.tb14705.x · Cited by 60
First menstruation and subsequent menstrual cycles of pubertal girls.
Engle, E. T., & Shelesnyak, M. C. (1934) · Human Biology · Cited by 56
The length of the human menstrual cycle
Fluhmann, C. F. (1934) · American Journal of Obstetrics and Gynecology · doi:10.1016/s0002-9378(34)90900-5 · Cited by 41
The length of the menstrual cycle
Haman, J. O. (1942) · American Journal of Obstetrics and Gynecology · doi:10.1016/s0002-9378(42)90968-2 · Cited by 34
The Irregularity of the Menstrual Function
Allen, E. (1933) · American Journal of Obstetrics and Gynecology · doi:10.1016/s0002-9378(16)41778-3 · Cited by 31
Further studies on the sterile and fertile periods in women
Latz, L. J., & Reiner, E. (1942) · American Journal of Obstetrics and Gynecology · doi:10.1016/s0002-9378(42)91334-6 · Cited by 16
Cited by
Sorted by citations
Azziz, R., Carmina, E., Dewailly, D., Diamanti-Kandarakis, E., Escobar-Morreale, H. F., Futterweit, W., Janssen, O. E., Legro, R. S., Norman, R. J., Taylor, A. E., et al. (2009) · Fertility and Sterility · doi:10.1016/j.fertnstert.2008.06.035 · Cited by 2,132
POLYCYSTIC OVARIES—A COMMON FINDING IN NORMAL WOMEN
POLSON, D. W., Wadsworth, J., Adams, J., & Franks, S. (1988) · The Lancet · doi:10.1016/s0140-6736(88)91612-1 · Cited by 899
Endocrine regulation of menstruation
Jabbour, H. N., Kelly, R. W., Fraser, H. M., & Critchley, H. O. D. (2006) · Endocrine Reviews · doi:10.1210/er.2004-0021 · Cited by 588
POLYCYSTIC OVARY SYNDROME: A CHANGING PERSPECTIVE
Franks, S. (1989) · Clinical Endocrinology · doi:10.1111/j.1365-2265.1989.tb00457.x · Cited by 523
Real-world menstrual cycle characteristics of more than 600,000 menstrual cycles
Bull, J. R., Rowland, S. P., Scherwitzl, E. B., Scherwitzl, R., Danielsson, K. G., & Harper, J. (2019) · npj Digital Medicine · doi:10.1038/s41746-019-0152-7 · Cited by 404
“With increasing age, cycle length reduces and the timing of ovulation becomes earlier; the variation of a woman’s cycle length reduces with age until menopause.(5,6,8,9) Cycle characteristics also may be affected by ethnicity, high body mass index (BMI), stress and lifestyle factors.”
BackgroundResult
Metadata
- Authors
- Chiazze, L.
- Corresponding author
- Chiazze, Leonard
- Venue
- JAMA: The Journal of the American Medical Association
- Publisher
- American Medical Association (AMA)
- Published
- 1968-02-05
- Volume
- 203
- Issue
- 6
- Pages
- 377
- ISSN
- 0002-9955 (ISSN-L)
- 0098-7484
- OpenAlex
- W2027829650
- Cited by
- 374
- References
- 12
- Citations by year
- 2026: 4 · 2025: 8 · 2024: 4 · 2023: 10 · 2022: 11 · 2021: 10 · 2020: 14 · 2019: 11 · 2018: 7 · 2017: 7 · 2016: 10 · 2015: 15 · 2014: 12 · 2013: 21 · 2012: 12
- FWCI
- 27.35
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- JAMA (publishedVersion)
- PubMed (publishedVersion)
- Topics
- Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Menstrual Health and Disorders
- Health Sciences › Medicine › Reproductive Medicine › Hypothalamic control of reproductive hormones
- Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Reproductive Health and Contraception
- Keywords
- menstrual cycle length, menstrual cycle variability, cycle length distribution, age differences, women's reproductive health
- MeSH terms
- Adult, Age Factors, Female, Humans, Menopause, Menstruation, Middle Aged, Prospective Studies, Statistics as Topic, Time Factors
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