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Irregular menstruation
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<h2 id="irregular-cycles-or-periods">Irregular cycles or periods</h2> <p>Irregular cycles or irregular periods is an abnormal variation in length of <a href="/facts/Menstrual_cycle/AY6Y9xxM">menstrual cycles</a>. An individual usually experiences cycle length variations of up to eight days between the shortest and longest cycle lengths. Lengths <a href="/facts/Range_(statistics)/Yu0HgeRj">ranging</a> between eight and 20 days are considered moderately irregular.<a class="footnote-ref" id="fnref:6" href="#fn:6"><sup>6</sup></a> Variation of 21 days or more is considered very irregular.<a class="footnote-ref" id="fnref:7" href="#fn:7"><sup>7</sup></a> </p><p>Alternatively, a single menstruation cycle may be defined as irregular if it is less than 24 days or more than 38 days.<a class="footnote-ref" id="fnref:8" href="#fn:8"><sup>8</sup></a> If they are regularly shorter than 21 days or longer than 36 (or 35) days, the condition is termed <a href="/facts/Polymenorrhea/06n59DW5">polymenorrhea</a> or <a href="/facts/Oligomenorrhea/cBAsRfxG">oligomenorrhea</a>, respectively.<a class="footnote-ref" id="fnref:9" href="#fn:9"><sup>9</sup></a> </p><p>Additionally, irregular menstruation is common in adolescence.<a class="footnote-ref" id="fnref:10" href="#fn:10"><sup>10</sup></a> A regular menstrual cycle can be set within a year of <a href="/facts/Menarche/EFzGSWMk">menarche</a>.<a class="footnote-ref" id="fnref:11" href="#fn:11"><sup>11</sup></a> However, other studies suggest that it can take anywhere between 2<a class="footnote-ref" id="fnref:12" href="#fn:12"><sup>12</sup></a> and 7<a class="footnote-ref" id="fnref:13" href="#fn:13"><sup>13</sup></a><a class="footnote-ref" id="fnref:14" href="#fn:14"><sup>14</sup></a><a class="footnote-ref" id="fnref:15" href="#fn:15"><sup>15</sup></a> years to establish regularity after an individual's first menses. </p> <h2 id="other-types">Other types</h2> <p>Other types of conditions that can be referred to by "irregular menstruation" include: </p> <ul><li><a href="/facts/Metrorrhagia/pgysn5pd">Metrorrhagia</a>, which generally refers to <a href="/facts/Vaginal_bleeding/wLT7D34y">vaginal bleeding</a> that occurs between the expected <a href="/facts/Menstrual_period/AY6Y9xxM">menstrual periods</a>.<a class="footnote-ref" id="fnref:16" href="#fn:16"><sup>16</sup></a> The distinction between irregular cycle lengths and metrorrhagia is not always clear. It may depend on whether the bleeding is regarded as marking the menstrual period (favoring the term "irregular cycles") or being separate from it (favoring the term "metrorrhagia").</li> <li><a href="/facts/Oligomenorrhea/cBAsRfxG">Oligomenorrhea</a> generally refers to infrequent menstruation, More strictly, it is menstrual periods occurring at intervals of greater than 35 days, with only four to nine periods in a year.<a class="footnote-ref" id="fnref:17" href="#fn:17"><sup>17</sup></a> Menstrual periods should have been regularly established before the development of infrequent flow and often (but not always) involves irregular intervals. In contrast to "irregular cycles", the interval between one cycle and the next may be consistent but can be regarded as "irregular" compared to the cycle length of a female without oligomenorrhea. Women with oligomenorrhea often have irregular cycles as well.</li> <li><i>Polymenorrhea</i> is the medical term for cycles with intervals of 21 days or fewer. It can be regarded as the opposite of oligomenorrhea.<a class="footnote-ref" id="fnref:18" href="#fn:18"><sup>18</sup></a></li></ul> <h2 id="external-links">External links</h2> <h2 id="references">References</h2> <ol> <li id="fn:1"><p>Bae, Jinju; Park, Susan; Kwon, Jin-Won (2018-02-06). "Factors associated with menstrual cycle irregularity and menopause". BMC Women's Health. 18 (1): 36. doi:10.1186/s12905-018-0528-x. ISSN 1472-6874. PMC 5801702. PMID 29409520. <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5801702" target="_blank">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5801702</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li> <li id="fn:2"><p>Laganà, Antonio Simone; Veronesi, Giovanni; Ghezzi, Fabio; Ferrario, Marco Mario; Cromi, Antonella; Bizzarri, Mariano; Garzon, Simone; Cosentino, Marco (2022-01-01). "Evaluation of menstrual irregularities after COVID-19 vaccination: Results of the MECOVAC survey". Open Medicine. 17 (1): 475–484. doi:10.1515/med-2022-0452. ISSN 2391-5463. PMC 8919838. PMID 35350834. <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8919838" target="_blank">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8919838</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li> <li id="fn:3"><p>Muhaidat, Nadia; Alshrouf, Mohammad A.; Azzam, Muayad I.; Karam, Abdulrahman M.; Al-Nazer, Majed W.; Al-Ani, Abdallah (2022-03-28). "Menstrual Symptoms After COVID-19 Vaccine: A Cross-Sectional Investigation in the MENA Region". International Journal of Women's Health. 14: 395–404. doi:10.2147/IJWH.S352167. PMC 8976114. PMID 35378876. <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8976114" target="_blank">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8976114</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li> <li id="fn:4"><p>Edelman, Alison; Boniface, Emily R.; Benhar, Eleonora; Han, Leo; Matteson, Kristen A.; Favaro, Carlotta; Pearson, Jack T.; Darney, Blair G. (2022-05-05). "Association Between Menstrual Cycle Length and Coronavirus Disease 2019 (COVID-19) Vaccination: A U.S. Cohort". Obstetrics & Gynecology. 139 (4): 481–489. doi:10.1097/AOG.0000000000004695. ISSN 0029-7844. PMC 8936155. PMID 34991109. <a href="https://journals.lww.com/greenjournal/fulltext/9900/association_between_menstrual_cycle_length_and.357.aspx" target="_blank">https://journals.lww.com/greenjournal/fulltext/9900/association_between_menstrual_cycle_length_and.357.aspx</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li> <li id="fn:5"><p>Laganà, Antonio Simone; Veronesi, Giovanni; Ghezzi, Fabio; Ferrario, Marco Mario; Cromi, Antonella; Bizzarri, Mariano; Garzon, Simone; Cosentino, Marco (2022-01-01). "Evaluation of menstrual irregularities after COVID-19 vaccination: Results of the MECOVAC survey". Open Medicine. 17 (1): 475–484. doi:10.1515/med-2022-0452. ISSN 2391-5463. PMC 8919838. PMID 35350834. <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8919838" target="_blank">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8919838</a> <a href="#fnref:5" class="footnote-back-ref">↩</a></p></li> <li id="fn:6"><p>Kippley, John; Sheila Kippley (1996). The Art of Natural Family Planning (4th ed.). Cincinnati, OH: The Couple to Couple League. p. 92. ISBN 0-926412-13-2. <a href="0-926412-13-2" target="_blank">0-926412-13-2</a> <a href="#fnref:6" class="footnote-back-ref">↩</a></p></li> <li id="fn:7"><p>Kippley, John; Sheila Kippley (1996). The Art of Natural Family Planning (4th ed.). Cincinnati, OH: The Couple to Couple League. p. 92. ISBN 0-926412-13-2. <a href="0-926412-13-2" target="_blank">0-926412-13-2</a> <a href="#fnref:7" class="footnote-back-ref">↩</a></p></li> <li id="fn:8"><p>"Period problems?". womenshealth.gov. Retrieved 2018-11-07. <a href="https://www.womenshealth.gov/menstrual-cycle/period-problems" target="_blank">https://www.womenshealth.gov/menstrual-cycle/period-problems</a> <a href="#fnref:8" class="footnote-back-ref">↩</a></p></li> <li id="fn:9"><p>"What are menstrual irregularities?". nichd.nih.gov/. 31 January 2017. Retrieved 2018-11-07. <a href="https://www.nichd.nih.gov/health/topics/menstruation/conditioninfo/irregularities" target="_blank">https://www.nichd.nih.gov/health/topics/menstruation/conditioninfo/irregularities</a> <a href="#fnref:9" class="footnote-back-ref">↩</a></p></li> <li id="fn:10"><p>"Menstruation in Girls and Adolescents: Using the Menstrual Cycle as a Vital Sign". American College of Obstetricians and Gynecologists. Retrieved 5 July 2020. <a href="https://www.acog.org/clinical/clinical-guidance/committee-opinion/articles/2015/12/menstruation-in-girls-and-adolescents-using-the-menstrual-cycle-as-a-vital-sign" target="_blank">https://www.acog.org/clinical/clinical-guidance/committee-opinion/articles/2015/12/menstruation-in-girls-and-adolescents-using-the-menstrual-cycle-as-a-vital-sign</a> <a href="#fnref:10" class="footnote-back-ref">↩</a></p></li> <li id="fn:11"><p>Zhang, Katie; Pollack, Staci; Ghods, Ali; Dicken, Carrie; Isaac, Barbara; Adel, Goli; Zeitlian, Gohar; Santoro, Nanette (2008). "Onset of Ovulation after Menarche in Girls: A Longitudinal Study". The Journal of Clinical Endocrinology and Metabolism. 93 (4): 1186–94. doi:10.1210/jc.2007-1846. PMC 2291492. PMID 18252789. <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2291492" target="_blank">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2291492</a> <a href="#fnref:11" class="footnote-back-ref">↩</a></p></li> <li id="fn:12"><p>Legro, Richard S.; Lin, Hung Mo; Demers, Laurence M.; Lloyd, Tom (March 1, 2000). "Rapid Maturation of the Reproductive Axis during Perimenarche Independent of Body Composition". The Journal of Clinical Endocrinology and Metabolism. 85 (3): 1021–1025. doi:10.1210/jcem.85.3.6423. PMID 10720033. <a href="https://doi.org/10.1210%2Fjcem.85.3.6423" target="_blank">https://doi.org/10.1210%2Fjcem.85.3.6423</a> <a href="#fnref:12" class="footnote-back-ref">↩</a></p></li> <li id="fn:13"><p>Engle, E.T.; SHELESNYAK, M.C. (1934). "First Menstruation and Subsequent Menstrual Cycles of Pubertal Girls". Human Biology. 6 (3): 431–453. JSTOR 41447202. <a href="/wiki/JSTOR_(identifier)" target="_blank">/wiki/JSTOR_(identifier)</a> <a href="#fnref:13" class="footnote-back-ref">↩</a></p></li> <li id="fn:14"><p>Treloar, A.E.; Boynton, R.E.; Behn, B.G.; Brown, B.W. (1967). "Variation of the human menstrual cycle through reproductive life". International Journal of Fertility. 1 (2): 77–126 – via POPLINE. <a href="https://www.popline.org/node/508523" target="_blank">https://www.popline.org/node/508523</a> <a href="#fnref:14" class="footnote-back-ref">↩</a></p></li> <li id="fn:15"><p>Vollman, R.F. (1977). "The Menstrual Cycle". Major Problems in Obstetrics and Gynecology. 7. W.B. Saunders Co.: 1–193. PMID 836520 – via POPLINE. <a href="/wiki/PMID_(identifier)" target="_blank">/wiki/PMID_(identifier)</a> <a href="#fnref:15" class="footnote-back-ref">↩</a></p></li> <li id="fn:16"><p>"Vaginal bleeding between periods: MedlinePlus Medical Encyclopedia". medlineplus.gov. Retrieved 2018-11-07. <a href="https://medlineplus.gov/ency/article/003156.htm" target="_blank">https://medlineplus.gov/ency/article/003156.htm</a> <a href="#fnref:16" class="footnote-back-ref">↩</a></p></li> <li id="fn:17"><p>"What are menstrual irregularities?". nichd.nih.gov/. 31 January 2017. Retrieved 2018-11-07. <a href="https://www.nichd.nih.gov/health/topics/menstruation/conditioninfo/irregularities" target="_blank">https://www.nichd.nih.gov/health/topics/menstruation/conditioninfo/irregularities</a> <a href="#fnref:17" class="footnote-back-ref">↩</a></p></li> <li id="fn:18"><p>"What are menstrual irregularities?". nichd.nih.gov/. 31 January 2017. Retrieved 2018-11-07. <a href="https://www.nichd.nih.gov/health/topics/menstruation/conditioninfo/irregularities" target="_blank">https://www.nichd.nih.gov/health/topics/menstruation/conditioninfo/irregularities</a> <a href="#fnref:18" class="footnote-back-ref">↩</a></p></li> </ol>