{"paper_id":"cbe0156e-060a-4865-b87f-9bff83d18f7c","body_text":"Advances in Reproductive Sciences, 2025, 13(4), 313-322 \nhttps://www.scirp.org/journal/arsci \nISSN Online: 2330-0752 \nISSN Print: 2330-0744 \n \nDOI: 10.4236/arsci.2025.134026  Oct.  29, 2025 313 Advances in Reproductive Sciences \n \n \n \n \nPrevalence, Clinical Characteristics, and \nFactors Associated with the Severity of  \nPrimary Dysmenorrhea among Adolescent \nGirls in Douala (Cameroon) \nMichèle Florence Mendoua1*, Isabelle Mekone2, Junie Ngaha1, Gervais Mounchikpou Ngouhouo1, \nBilkissou Moustapha1, Charlotte Tchente Nguefack1, Emile Mboudou3 \n1Department of Surgery and Specialties, Faculty of Medicine and Pharmaceutical Sciences, University of Douala, Douala,  \nCameroon \n2Department of Pediatrics, Faculty of Medicine and Biomedical Sciences, University of Yaounde I, Yaounde, Cameroon \n3Department of Obstetrics and Gynecology, Faculty of Medicine and Biomedical Sciences, University of Yaounde I, Yaounde, \nCameroon \n \n \n \nAbstract \nIntroduction : Primary dysmenorrhea is the most frequent cause of pelvic pain \nin adolescent girls and constitutes a major public health problem. In Douala, \nits clinical characteristics and determinants of severity remain understudied. \nThe objective of this study was to determine the prevalence, describe the clin-\nical characteristics, and identify the factors associated with the severity of pri-\nmary dysmenorrhea among school -going adolescent girls in Douala. Meth-\nods: A cross-sectional analytical study was conducted from October 2023 to \nApril 2024 in five secondary schools in Douala. A total of 1,045 adolescent \ngirls aged 13 - 19 years were randomly selected. Data, collected via a self -ad-\nministered questionnaire, covered socio -demographic, gynecological, and \nclinical characteristics. Pain intensity was evaluated using a Visual Analog \nScale (VAS). Associations between dysmenorrhe a severity and menstrual \ncharacteristics were explored by logistic regression. Results : The prevalence of \nprimary dysmenorrhea was 76.5% (800/1,045). The mean age at menarche was \n12.9 ± 1.5 years. Pain most often occurred from the first day of menses \n(66.5%), lasted more than 24 hours in 56.8% of cases, and was localized to the \nlower abdomen (71.8\n%). Associated symptoms included headaches (39.7%), \nbreast pain (35.2%), and nervousness (32.6%). Severe pain was significantly \nassociated with irregular cycles (OR = 1.52; p = 0.017), prolonged menstrua-\ntion ≥6 days (OR = 2.45; p < 0.001), heavy menstrual flow (OR = 2.31; p < \nHow to cite this paper: Mendoua, M.F., \nMekone, I., Ngaha, J., Ngouhouo, G.M., \nMoustapha, B., Nguefack, C.T. and Mbou-\ndou, E. (2025) Prevalence, Clinical Charac-\nteristics, and Factors Associated with the \nSeverity of Primary Dysmenorrhea among \nAdolescent Girls in Douala (Cameroon). \nAdvances in Reproductive Sciences, 13, \n313-322. \nhttps://doi.org/10.4236/arsci.2025.134026 \n \nReceived:  September 19, 2025 \nAccepted:  October 26, 2025 \nPublished:  October 29, 2025 \n \nCopyright © 2025 by author(s) and  \nScientific Research Publishing Inc. \nThis work is licensed under the Creative \nCommons Attribution International  \nLicense (CC BY 4.0). \nhttp://creativecommons.org/licenses/by/4.0/   \n  \nOpen Access\n\nM. F. Mendoua et al. \n \n \nDOI: 10.4236/arsci.2025.134026 314 Advances in Reproductive Sciences \n \n0.001), and pain occurring every cycle (OR = 2.04; p < 0.001). Conclusion : \nPrimary dysmenorrhea affects more than three-quarters of adolescent girls in \nDouala. Its severity is associated with menstrual characteristics (irregularity, \nlonger duration, and heavy flow of menses). These results underscore the need \nto integrate menstrual health education and psychological support into school \nprograms to reduce its impact on young girls’ quality of life and schooling. \n \nKeywords \nPrimary Dysmenorrhea, Adolescent, Prevalence, Clinical Characteristics,  \nSeverity Factors, Cameroon \n \n1. Introduction \nPrimary dysmenorrhea, defined as recurrent pelvic pain during menstruation in \nthe absence of identifiable pelvic pathology, is the most common gynecological \ncondition in adolescence and early reproductive life [1]. It is mainly due to an \nexcessive production of prostaglandins leading to uterine hypercontractility and \ntransient myometrial ischemia [2]. Its reported frequency varies widely, ranging \nfrom 45% to 95% worldwide, with particularly high rates observed among second-\nary school and university students [3] [4]. In recent years, several surveys have \nconfirmed that more than two out of three adolescent girls suffer from dysmen-\norrhea, notably in Africa and Asia [5]-[7]. In Cameroon, dysmenorrhea has been \nreported in over half of female students in Dschang [8] and in over 70% in Ya-\noundé [9]. However, few studies have focused on Douala, the economic capital of \nthe country, where academic and social pressures are high and the impact of dys-\nmenorrhea on adolescent health remains underexplored. Furthermore, detailed \ndescriptions of clinical chara cteristics and analyses of severity factors are limited \nin the local literature. It is in this context that we conducted the present study, \nwith the aim of estimating the prevalence of primary d ysmenorrhea among ado-\nlescent girls in Douala, describing its clinical manifestations, and identifying the \nmain factors associated with its severity. \n2. Methods \n2.1. Study Design and Setting \nWe conducted a cross-sectional analytical study among adolescent schoolgirls in \nthe city of Douala, the economic capital of Cameroon. The survey took place from \nOctober 2023 to April 2024 in five secondary schools selected to represent the \nsocio-economic and educational diversity of the city. \n2.2. Study Population \nThe target population consisted of girls aged 13 to 19 years who had already \nstarted menstruating. We included students who were present at the time of the \n\nM. F. Mendoua et al. \n \n \nDOI: 10.4236/arsci.2025.134026 315 Advances in Reproductive Sciences \n \nsurvey and provided informed consent. We excluded those older than 19 years, \nthose who refused to participate, and those with a known gynecological pathology \nthat could explain pelvic pain (such as endometriosis or uterine malformations). \nPrimary dysmenorrhea was defined as menstrual pain occurring in the absence of \nany identifiable pelvic pathology. \n2.3. Sampling and Sample Size \nParticipants were randomly selected from class rosters. The sample size was cal-\nculated assuming an anticipated prevalence of 50%, a 95% confidence level, and a \n5% precision. In total, 1045 adolescent girls were recruited. \n2.4. Data Collection \nData were collected using an anonymous self-administered questionnaire that was \npre-tested prior to the study. The questionnaire covered: \n• Socio-demographic  characteristics : age, marital status, educational level, \nbody mass index (BMI), family history of dysmenorrhea; \n• Gynecological  history : age at menarche, regularity of menstrual cycles, dura-\ntion and flow of menses; \n• Clinical  characteristics  of menstrual  pain: intensity, duration, location, asso-\nciated symptoms; \n• Assessment  of menstrual  pain severity : measured using a 0 - 10 Visual Ana-\nlog Scale (VAS) and categorized into three levels: mild (1 - 3), moderate (4 - \n6), and severe (7 - 10). \n2.5. Statistical Analysis \nData were entered and analyzed using SPSS software version 25.0. Qualitative var-\niables were expressed as frequencies and percentages, and quantitative variables \nas means ± standard deviation. Comparisons were made using Pearson’s chi-\nsquare test. Factors associated with dysmenorrhea severity were explored using \nbinary logistic regression. Statistical significance was set at p < 0.05. The co-vari-\nables included in the logistic regression model were: age, BMI, age at menarche, \ncycle regularity, duration of menses, flow volume, frequency of menstrual pain, \nand family history of dysmenorrhea. Model fit was verified using the Hosmer-\nLemeshow test (p > 0.05). \n2.6. Ethical Considerations \nThe study was approved by the Institutional Ethics Committee of the University \nof Douala. Administrative authorization was obtained from the heads of the par-\nticipating schools. Participation was voluntary, with informed consent obtained \nfrom the adolescents and, for minors, from their parents or legal guardians. Ano-\nnymity and data confidentiality were ensured. \n3. Results \nA total of 1200 students were enumerated in the five selected secondary schools. \n\nM. F. Mendoua et al. \n \n \nDOI: 10.4236/arsci.2025.134026 316 Advances in Reproductive Sciences \n \nAfter applying the exclusion criteria, 155 adolescents were removed from the \nstudy: 90 did not provide consent, 40 were older than 19 years, and 25 did not \nmeet the inclusion criteria. Thus, 1045 participants were included in the final anal-\nysis. Among them, 800 reported suffering from primary dysmenorrhea, corre-\nsponding to a prevalence of 76.5%, while 245 (23.5%) reported no menstrual pain \n(Figure 1 ). \n \n \nFigure 1.  Flow diagram of participant selection. \n3.1. Overall Population Characteristics and Dysmenorrhea  \nPrevalence \nA total of 1,045 adolescent girls aged 13 to 19 years were included in the study. \nThe mean age was 17 ± 1.2 years. The majority of participants were single and in \nthe second cycle of secondary education (upper secondary school). Of the 1045 \ngirls surveyed, 800 reported experiencing primary dysmenorrhea, yielding a prev-\nalence of 76.5%. \n3.2. Clinical Characteristics of Dysmenorrheic Adolescents \n3.2.1. Distribution by BMI and Menarche \nIn our study, 67.0% of dysmenorrheic adolescents had a normal BMI; 11.0% were \noverweight and 22.0% were obese. The most common age at menarche was 13 \nyears (26.5% of participants). The mean age at menarche was 12.88 ± 1.46 years, \nwith extremes of 9 and 17 years (Figure 2 ). \n3.2.2. Menstrual Characteristics \nAmong the 800 dysmenorrheic adolescents, menstrual cycles were regular in \nnearly three-quarters of cases (75.3%), while one-quarter (24.7%) reported irreg-\nular cycles. The duration of menses was 4 - 5 days for more than half of the par-\nticipants (56.5%). Nearly one-third (30.7%) had prolonged menstruation lasting \nsix days or more, whereas 12.8% reported short menses of three days or less. Re-\ngarding menstrual flow, the majority of adolescents described a moderate flow \n(62.6%), versus 22.9% who reported it as heavy and 14.5% who considered it light. \nFinally, the frequency of menstrual pain was particularly high: more than seven in \n\n\nM. F. Mendoua et al. \n \n \nDOI: 10.4236/arsci.2025.134026 317 Advances in Reproductive Sciences \n \nten adolescents (70.5%) suffered dysmenorrhea at each cycle, while one in five \n(20.8%) experienced it every other cycle and 8.7% only occasionally (Table 1 ). \n \n \nFigure 2.  Distribution of dysmenorrheic adolescents according to BMI and age at menarche. \n \nTable 1 . Menstrual characteristics among dysmenorrheic adolescents (n = 800). \nVariables  Categories  n % \nCycle regularity  \nRegular 602 75.3 \nIrregular 198 24.7 \nDuration  of menses  \n(days) \n≤3 102 12.8 \n4 - 5 452 56.5 \n≥6 246 30.7 \nMenstrual  flow \nLight 116 14.5 \nModerate 501 62.6 \nHeavy 183 22.9 \nFrequency  of dys-\nmenorrhea  \nEvery cycle 564 70.5 \nEvery other cycle 166 20.8 \nMore rarely 70 8.7 \n3.2.3. Dysmenorrhea Characteristics \nAmong the 800 dysmenorrheic adolescents, menstrual pain appeared after the \nfirst year of menstruation in nearly seven out of ten cases (68%), while one-third \nreported an onset during the first year following menarche. The timing of pain \nonset most often coincided with the beginning of the menstrual flow (66.5%). It \noccurred less frequently before menstruation (10.0%) or during menses (7.8%), \nand only exceptionally at the end of menses (1.2%). The pain duration generally \nexceeded 24 hours: more than half of the adolescents (56.8%) reported prolonged \npersistence, whereas 17.0% reported a duration limited to one day and 3.8% ex-\nperienced pain lasting less than 24 hours. The pain location was primarily pelvic, \n\n\nM. F. Mendoua et al. \n \n \nDOI: 10.4236/arsci.2025.134026 318 Advances in Reproductive Sciences \n \nwith a clear predominance in the lower abdomen (71.8%). Some adolescents re-\nported radiation of pain to the lower back (7.3%) or to the lower limbs (2.8%). \nRegarding intensity, the pain was described as moderate by about two out of five \nparticipants (40.5%), severe in 17.2% of cases, and mild in 22.8%. Finally, pain \nfrequency showed that 40.0% of the adolescents experienced it occasionally, 13.2% \nfrequently, and 31.3% constantly with each menstruation (Table 2 ). \n \nTable 2 . Dysmenorrhea characteristics among dysmenorrheic adolescents (n = 800). \nCharacteristic  Category  n % \nDelay of onset after  \nmenarche  \nWithin first year (ref.) 256 32.0 \nAfter the first year 544 68.0 \nTiming of pain onset \nBefore menses 80 10.0 \nAt start of menses 532 66.5 \nDuring menses 62 7.8 \nEnd of menses 10 1.2 \nDuration  of pain \n<24 h 30 3.8 \n=24 h 136 17.0 \n>24 h 454 56.8 \nPain location  \nLower abdomen 574 71.8 \nLower back 58 7.3 \nRadiating to legs 22 2.8 \nPain intensity  \nMild 182 22.8 \nModerate 324 40.5 \nSevere 138 17.2 \nPain frequency  \nOccasional 320 40.0 \nFrequent 106 13.2 \nConstant 250 31.3 \n3.3. Associated Symptoms of Dysmenorrhea \nAmong the 800 adolescents reporting dysmenorrhea, 80.7% indicated at least one \nassociated symptom. Headaches were the most frequent symptom, reported by \n39.7% of participants, followed by breast pain (35.2%) and nervousness (32.6%). \nPsychological symptoms such as depressive mood (27.3%) and insomnia (18.3%) \nwere also reported, reflecting the emotional and behavioral impact of menstrual \npain. On the digestive side, abdominal bloating (22.3%), nausea (16.9%), diarrhea \n(19.8%), and more rarely vomiting (5.0%) accompanied the symptomatology. \nFainting, although rare (0.6%), attests to very severe presentations. These results \nconfirm that dysmenorrhea in adolescents is accompanied by a wide range of so-\nmatic, psychological, and functional manifestations, which can increase morbidity \nand impair quality of life both in school and social contexts (Figure 3 ). \n\nM. F. Mendoua et al. \n \n \nDOI: 10.4236/arsci.2025.134026 319 Advances in Reproductive Sciences \n \n \nFigure 3.  Symptoms associated with dysmenorrhea. \n3.4. Factors Associated with Dysmenorrhea Severity \nThe analysis of pain intensity relative to menstrual characteristics revealed several \nsignificant associations. Adolescents with irregular cycles reported severe pain \nmore often than those with  regular cycles (22.0% vs 15.0%; OR = 1.52; 95% CI: \n1.10-2.12; p = 0.017). Similarly, longer menstrual duration increased pain inten-\nsity: severe pain was markedly more frequent when menses lasted six days or more \n(28.0%), compared to short menses (12.0%; OR = 2.45; 95% CI: 1.68 - 3.58; p < \n0.001). Heavy menstrual flow was also a determining factor: 27.0% of adolescents \nwith heavy flow suffered severe pain versus 13.0% of those with light flow (OR = \n2.31; 95% CI: 1.62 - 3.30; p < 0.001). Finally, the frequency of dysmenorrhea cor-\nrelated with pain severity: the proportion of severe pain rose from 11.0% in those \nwith occasional dysmenorrhea to 25.0% in those affected at every cycle (OR = 2.04; \n95% CI: 1.48 - 2.83; p < 0.001). These findings suggest that dysmenorrhea severity \nis heightened by irregular, prolonged, heavy, and very frequent menses, confirm-\ning the role of menstrual characteristics as predictive factors for intense pain in \nadolescent girls (Table 3 ). \n \nTable 3 . Association between pain intensity and menstrual characteristics (n = 800). \nMenstrual  characteristic  Category  Mild % Moderate  % Severe  % OR (95% CI) p-value \nCycle regularity  \nRegular (ref.) 24.0 41.0 15.0 1.00 – \nIrregular 20.0 38.0 22.0 1.52 (1.10 - 2.12) 0.017 \nDuration  of menses  \n≤3  days (ref.) 28.0 35.0 12.0 1.00 – \n4 - 5 days 24.0 42.0 17.0 1.38 (0.96 - 1.98) 0.074 \n≥6  days 18.0 36.0 28.0 2.45 (1.68 - 3.58) <0.001 \n\n\nM. F. Mendoua et al. \n \n \nDOI: 10.4236/arsci.2025.134026 320 Advances in Reproductive Sciences \n \nContinued  \nMenstrual  flow \nLight (ref.) 27.0 39.0 13.0 1.00 – \nModerate 23.0 41.0 16.0 1.26 (0.91 - 1.74) 0.15 \nHeavy 18.0 34.0 27.0 2.31 (1.62 - 3.30) <0.001 \nDysmenorrhea   \nfrequency  \nOccasional (ref.) 28.0 39.0 11.0 1.00 – \nEvery other cycle 22.0 40.0 18.0 1.52 (1.05 - 2.22) 0.028 \nEvery cycle 19.0 38.0 25.0 2.04 (1.48 - 2.83) <0.001 \n4. Discussion \nThe present study shows a high prevalence of primary dysmenorrhea (76.5%) \namong school-going adolescent girls in Douala. Our results are in line with those \nreported in other sub-Saharan African countries, where prevalence reaches \naround 70% on average [3]-[5]. For instance, a prevalence of 72% was described \nin Yaoundé [9], while in Dschang it was 55% [8]. In Ethiopia, Mammo et al. re-\nported 72% of adolescents affected [5], and Gindaba et al. found similar rates [6]. \nThese contextual differences may be explained by the diversity of socio-cultural \ndeterminants, the level of academic stress, and access to healthcare [8] [9]. \nClinically, the mean age at menarche observed (12.9 years) is consistent with \nrecent data from Africa [3] [6] [7] and Asia [10]. The menstrual characteristics \nidentified (irregular cycles, prolonged and heavy periods) emerged as significant \nfactors associated with severity. These results corroborate findings from Ethiopia \nand Palestine, which show that long durations of bleeding and heavy flow double \nthe risk of severe pain [5]-[7]. The most widely accepted pathophysiological ex-\nplanation is an excessive production of prostaglandins, which is elevated in cases \nof heavy and prolonged periods, leading to increased uterine hypercontractility \nand myometrial ischemia [2] [11]. \nAssociated symptoms were frequent (80.7%), dominated by headaches, diges-\ntive disturbances, and nervousness. This polymorphic symptom profile has been \nreported in other recent studies, notably in Brazil [12] and in Palestine [7]. The \npsychological impact merits particular attention: nearly one-third of our partici-\npants reported depressive mood or insomnia, confirming the results of Liu et al. \nwho established a direct link between chronic stress, anxiety, and dysmenorrhea \nintensity [13]. \nThe magnitude of the problem among adolescents calls for a public health re-\nsponse. Approaches focused solely on self-medication have proven insufficient \nand potentially deleterious [7] [14]. Schools thus appear to be strategic settings for \nscreening and management. In the Cameroonian context, the integration of men-\nstrual health modules into school curricula would be a pragmatic and realistic ad-\nvance [15]. \n5. Strengths and Limitations of the Study \nWe did not include analgesic use, physical activity, or caffeine consumption in our \n\nM. F. Mendoua et al. \n \n \nDOI: 10.4236/arsci.2025.134026 321 Advances in Reproductive Sciences \n \nanalysis, as these factors are considered therapeutic interventions or coping meth-\nods used by the adolescents rather than intrinsic determinants of dysmenorrhea \nseverity. Nonetheless, their role deserves to be explored in future studies. \nOur study has several strengths, notably the large sample size and the repre-\nsentativeness of the Douala secondary schools, which confer robust validity to the \nresults. However, certain limitations exist, including the self-reported nature of \nthe data (a potential source of recall bias) and the absence of ultrasound evalua-\ntion, which means some secondary causes of pelvic pain could not be entirely \nruled out. Despite these limitations, this work adds to the local literature on ado-\nlescent dysmenorrhea. \n6. Conclusion \nPrimary dysmenorrhea affects more than three-quarters of adolescent girls in \nDouala, with severity correlated to long, heavy, and irregular menstrual periods. \nManagement should go beyond symptomatic treatment, including education, \npsychological support, and the integration of menstrual health initiatives in \nschools. \nAuthors’ Contributions \nAll authors participated in the conception and writing of this work. \nConflicts of Interest \nThe authors declare no conflicts of interest regarding the publication of this paper. \nReferences \n[1] Ju, H., Jones, M. and Mishra, G. 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