{"paper_id":"1561b6f0-79f2-42b2-8812-a65bd7aaa5cb","body_text":"~ 894 ~ \nInternational Journal of Clinical Obstetrics and Gynaecology 2026;10(2): 894-901 \n \nISSN (P): 2522-6614 \nISSN (E): 2522-6622 \nIndexing: Embase \nImpact Factor (RJIF): 6.71 \n© Gynaecology Journal \nwww.gynaecologyjournal.com \n2026;10(2): 894-901 \nReceived: 07-01-2026 \nAccepted: 11-02-2026 \n \nDr. Sayani Das \nAssistant Professor, Department of \nObstetrics and Gynaecology, MJN \nMedical College, Cooch Bihar, West \nBengal, India \n \nDr. Bibekananda Das \nAssociate Professor,  \nDepartment of Obstetrics and \nGynaecology, Barasat govt medical \ncollege. North 24 PGS Kolkata \nwest Bengal, India \n \nDr. Kajal Kumar Patra \nEx Professor and HOD \nGynaecology and Obstetrics, Gouri \nDevi institute of medical science \nDurgapur, West Bengal, India \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \nCorresponding Author: \nDr. Kajal Kumar Patra \nEx Professor and HOD \nGynaecology and Obstetrics, Gouri \nDevi institute of medical science \nDurgapur, West Bengal, India \n \nComparative efficacy of dienogest versus levonorgestrel-\nreleasing intrauterine system in the symptom control of \nadenomyosis: A randomized controlled trial \n \nSayani Das, Bibekananda Das and Kajal Kumar Patra \n \nDOI: https://www.doi.org/10.33545/gynae.2026.v10.i2l.2135  \n \nAbstract \nBackground: Adenomyosis is a common benign uterine disorder associated with dysmenorrhea, chronic \npelvic pain, and heavy menstrual bleeding, often requiring long -term conservative treatment. Among \nmedical options, dienogest and the levonorgestrel -releasing intrauterine system (LNG -IUS) are widely \nused, but comparative evidence regarding their relative efficacy in symptom control remains limited.  \nObjective: To evaluate and compare the efficacy of dienogest and LNG -IUS in the symptom control of \nadenomyosis, with particular reference to pain relief, menstrual blood loss, ultrasonographic changes, and \nadverse effects.  \nMethods: This randomized controlled trial included 100 women with symptomatic adenomyosis, allocated \nequally to a dienogest group (2 mg orally once daily) or an LNG -IUS group. Participants were followed at \n3, 6, and 12 months. Pain symptoms were assessed using visual analog scale (VAS) scores for \ndysmenorrhea and chronic pelvic pain, while menstrual blood loss was evaluated using pictorial blood loss \nassessment chart (PBAC) scores. Ultrasonographic parameters included uterine volume and junctional zone \nthickness. Adverse effects and treatment continuation were also recorded. Follow -up outcome analyses \nwere performed on a per-protocol basis.  \nResults: Both treatment groups showed significant improvement in dysmenorrhea, chronic pelvic pain, and \nmenstrual blood loss over 12 months. Dienogest produced greater reduction in dysmenorrhea than LNG -\nIUS (between -group change p=0.010), whereas improvement in chronic pelvic pain was comparable \nbetween groups (p=0.458). LNG -IUS was superior in reducing menstrual blood loss, with significantly \nlower PBAC scores at 3, 6, and 12 months, and a higher proportion of marked menstrual blood loss \nresponse at 12 months (82.0% vs 48.0%, p=0.002). Both groups demonstrated significant ultrasonographic \nimprovement; reduction in junctional zone thickness favored LNG -IUS (between-group change p=0.002), \nwhile reduction in uterine volume was comparable. Treatment discontinuation/removal was significantly \nmore frequent in the LNG-IUS group than in the dienogest group (32.0% vs 4.0%, p<0.001).  \nConclusion: Both dienogest and LNG-IUS were effective in the conservative management of symptomatic \nadenomyosis. Dienogest provided better pain relief, particularly for dysmenorrhea, whereas LNG -IUS was \nmore effective in reducing menstrual blood loss and improving junctional zone thickness. Treatment choice \nshould therefore be individualized according to the predominant symptom profile and tolerability. \n \nKeywords: Adenomyosis, dienogest, levonorgestrel -releasing intrauterine system, dysmenorrhea, \nmenstrual blood loss \n \nIntroduction  \nAdenomyosis is a common benign uterine disorder characterized by the presence of endometrial \nglands and stroma within the myometrium, along with surrounding smooth muscle hyperplasia \nand hypertrophy. It is now understood as a complex condition rather than a simple \nhistopathological finding. Its pathogenesis appears multifactorial, involving tissue injury and \nrepair, hormonal influences, inflammation, fibrosis, and abnormal uterine peristalsis [1]. These \nmechanisms help explain why adenomyosis can produce persistent symptoms and why its \nclinical behavior varies from one woman to another. \nThe condition is increasingly recognized in women of reproductive age and is frequently \nassociated with dysmenorrhea, heavy menstrual bleeding, chronic pelvic pain, and infertility. \nClinical presentation is often variable, and diagnosis may be delayed because symptoms overlap \nwith other gynecological disorders such as fibroids and endometriosis [2]. Improved imaging, \nespecially transvaginal ultrasonography and magnetic resonance imaging, has made noninvasive \ndiagnosis more practical, but adenomyosis still remains underdiagnosed in many settings [2].  \n\n\nInternational Journal of Clinical Obstetrics and Gynaecology https://www.gynaecologyjournal.com \n~ 895 ~ \nThe burden of disease is considerable because symptoms may be \nprolonged, recurrent, and severe enough to interfere with daily \nactivity and quality of life. \nManagement of adenomyosis remains challenging. Treatment \ndepends on symptom severity, age, reproductive plans, extent of \ndisease, and patient preference. Historically, hysterectomy was \nconsidered the definitive treatment, particularly in women with \nsevere symptoms who had completed childbearing [3]. Many \npatients, however, seek uterus -preserving options. This has \nincreased the importance of conservative treatment strategies, \nespecially medical therapy, for controlling pain and abnormal \nuterine bleeding [3, 7]. \nAmong available medical options, progestin -based therapies \nhave gained particular importance. Dienogest is widely used \nbecause of its anti -inflammatory, anti -proliferative, and \nprogesterone-mediated effects on ectopic endometrial tissue. It \nhas shown benefit in reducing pain symptoms in women with \nadenomyosis and is increasingly used as a long -term medical \ntreatment option [4, 7]. The levonorgestrel -releasing intrauterine \nsystem (LNG-IUS) is another important conservative treatment. \nIt acts locally on the endometrium and has been reported to be \nhighly effective in reducing menstrual blood loss and \ndysmenorrhea in women with adenomyosis [5, 8]. In long -term \nfollow-up studies, LNG -IUS has shown sustained symptom \nrelief, although side effects such as irregular bleeding and device \nexpulsion may occur [7]. \nThere is growing interest in comparing these two treatment \nmodalities because they differ in route of administration, \nmechanism of action, side -effect profile, and patient \nacceptability. A recent systematic review and meta -analysis \ncomparing LNG -IUS and dienogest suggested that both are \neffective in the management of adenomyosis, but differences \nmay exist in the degree of symptom control and adverse effects \n[4]. This comparison is clinically important because adenomyosis \noften requires long -term treatment, and the choice of therapy \nmust balance efficacy, tolerability, compliance, and impact on \nquality of life. \nDespite expanding evidence, there is still no universal consensus \non the optimal conservative treatment for adenomyosis. The \ncondition itself is heterogeneous, and treatment response may \ndiffer according to symptom pattern, disease extent, and patient \ncharacteristics [1 ,2, 7]. In addition, adenomyosis remains an \nimportant cause of abnormal uterine bleeding and pelvic pain \namong women undergoing gynecologic evaluation, underlining \nthe need for practical and effective symptom -control strategies \n[6]. \nThe present study was undertaken to evaluate and compare the \nefficacy of dienogest and LNG -IUS in the symptom control of \nadenomyosis. The study specifically aimed to compare \nimprovement in pain symptoms and menstrual blood loss, assess \nultrasonographic changes after treatment, and evaluate the \nadverse effects associated with both treatment modalities \n \nAim \nTo evaluate and compare the efficacy of dienogest and LNG -\nIUS in the symptom control of adenomyosis. \n \nObjectives \n1. To compare improvement in pain symptoms and menstrual \nblood loss between the two treatment groups.  \n2. To compare ultrasonographic changes after treatment \nbetween the two groups.  \n3. To assess and compare the adverse effects associated with \nboth treatment modalities. \nMaterials and Methods \nStudy design \nThis study was a randomized controlled trial conducted to \ncompare the efficacy of dienogest and levonorgestrel -releasing \nintrauterine system (LNG -IUS) in the symptom control of \nadenomyosis. \n \nPlace of study \nThe study was carried out in the Department of Obstetrics and \nGynaecology Barasat govt medical college. North 24 pgs \nKolkata west Bengal \n \nStudy duration \nThe duration of the study was 1 year. \n \nSample size \nA total of 100 patients were included in the study. \n \nStudy population \nWomen diagnosed with symptomatic adenomyosis attending the \ngynecology outpatient department and fulfilling the eligibility \ncriteria were enrolled in the study. \n \nInclusion criteria \nPatients were included if they: \n• had adenomyosis diagnosed on clinical and \nultrasonographic assessment \n• had symptoms such as dysmenorrhea, chronic pelvic pain, \nand/or heavy menstrual bleeding attributable to \nadenomyosis \n• were willing to undergo treatment with either dienogest or \nLNG-IUS \n• were willing for regular follow-up \n• gave informed consent to participate in the study \n \nExclusion criteria \nPatients were excluded if they: \n• were pregnant or suspected to be pregnant \n• had coexisting large fibroids or other significant pelvic \npathology that could independently affect symptoms \n• had suspected or confirmed genital tract malignancy \n• had active pelvic inflammatory disease or genital tract \ninfection \n• had uterine cavity distortion or any contraindication to \nLNG-IUS insertion \n• had contraindications to progestin therapy \n• had severe systemic illness precluding participation \n• were unwilling for follow -up or had incomplete \nbaseline data \n \nRandomization and grouping \nAfter enrollment, the patients were randomized into two groups \nof 50 each: \n• Group A: Dienogest group \n• Group B: LNG-IUS group \n \nMethod of study \nA detailed history was taken from all patients, including age, \nparity, duration of symptoms, menstrual complaints, and pain \nsymptoms. Baseline clinical examination and ultrasonographic \nassessment were carried out before treatment. \nPatients in Group A received dienogest 2 mg orally once daily. \nPatients in Group B underwent insertion of a levonorgestrel -\n\nInternational Journal of Clinical Obstetrics and Gynaecology https://www.gynaecologyjournal.com \n~ 896 ~ \nreleasing intrauterine system (LNG -IUS) under standard aseptic \nprecautions. \n \nParameters assessed \n1. Pain symptoms \nPain was assessed using a visual analog scale (VAS). The major \npain symptoms evaluated included: \n• dysmenorrhea \n• chronic pelvic pain \n \nScores were recorded at baseline and during follow-up visits. \n \nMenstrual blood loss \nMenstrual blood loss was assessed using a pictorial blood loss \nassessment chart (PBAC) score. This was used to compare \nimprovement in bleeding symptoms between the two treatment \ngroups. \n \nUltrasonographic parameters \nUltrasonographic evaluation was done at baseline and during \nfollow-up. The parameters assessed included: \n• uterine volume \n• maximum myometrial thickness \n• junctional zone thickness \n \nThese parameters were used to assess structural changes \nfollowing treatment. \n \nAdverse effects \nThe adverse effects associated with both treatment modalities \nwere documented during follow-up. These included: \n• irregular bleeding or spotting \n• amenorrhea \n• weight gain \n• breast tenderness \n• mood changes \n• gastrointestinal symptoms \n• device expulsion \n• discontinuation or removal of treatment \n \nFollow-up \nAll patients were followed up at 3 months, 6 months, and 12 \nmonths after initiation of treatment. At each visit, pain \nsymptoms, menstrual blood loss, adverse effects, and treatment \ncontinuation were assessed. Ultrasonographic reassessment was \nalso performed during follow-up. \n \nOutcome measures \nThe primary outcome measures were: \n1. improvement in pain symptoms \n2. reduction in menstrual blood loss \n \nThe secondary outcome measures were: \n1. ultrasonographic changes after treatment \n2. adverse effects associated with both treatment modalities \n3. overall treatment response at 12 months \n \nStatistical analysis \nData were entered into Microsoft Excel and analyzed using \nappropriate statistical software. Quantitative variables were \nexpressed as mean ± standard deviation, and qualitative \nvariables were presented as frequency and percentage. \nComparison between the two groups for continuous variables \nwas performed using the independent t -test. Categorical \nvariables were compared using the chi -square test or Fisher’s \nexact test, as appropriate. Changes over follow-up were analyzed \nusing repeated-measures analysis. A p value less than 0.05 was \nconsidered statistically significant. \nA per -protocol analysis was performed. Only participants who \nremained on the assigned treatment and had evaluable outcome \ndata at the relevant follow-up visit were included in the analysis. \nParticipants who discontinued treatment, had device \nremoval/expulsion, or were lost to follow -up were excluded \nfrom analysis after the point of discontinuation. Therefore, the \nnumber analyzed at each follow -up time point could differ from \nthe number randomized. \n \nEthical considerations \nThe study was conducted after obtaining approval from the \nInstitutional Ethics Committee. Written informed consent was \nobtained from all participants before enrollment. Confidentiality \nof patient information was maintained throughout the study. \n \nData collection procedure \nEligible patients were enrolled after clinical and \nultrasonographic diagnosis of adenomyosis. Baseline \ndemographic, clinical, and ultrasonographic details were \nrecorded in a predesigned case record proforma. Patients were \nthen randomized into the dienogest and LNG -IUS groups. \nFollow-up assessments were carried out at 3, 6, and 12 months \nto record pain scores, menstrual blood loss, ultrasonographic \nchanges, adverse effects, and treatment continuation. \n \nResults \nA total of 100 women with adenomyosis were randomized \nequally to the dienogest group (n=50) or the levonorgestrel -\nreleasing intrauterine system (LNG-IUS) group (n=50). Baseline \ncharacteristics are presented for all randomized participants. \nFollow-up outcome analyses were performed on a per -protocol \nbasis and therefore included only those participants who \ncontinued the assigned treatment and had evaluable data at the \nrelevant visit. During follow -up, treatment \ndiscontinuation/removal occurred in 2 participants in the \ndienogest group and 16 participants in the LNG -IUS group. \nResults are presented according to baseline comparability, \nsymptomatic outcomes, ultrasonographic changes, and \ntreatment-related adverse effects. \n \nBaseline characteristics \nThe two randomized groups were comparable at baseline with \nrespect to age, body mass index, parity, symptom duration, \nuterine size, hemoglobin level, pain severity, menstrual blood \nloss, and baseline ultrasonographic parameters. No statistically \nsignificant intergroup differences were observed for baseline \nvariables, indicating adequate baseline balance between the trial \narms (Table 1). \n \n\nInternational Journal of Clinical Obstetrics and Gynaecology https://www.gynaecologyjournal.com \n~ 897 ~ \nTable 1: Baseline characteristics of the study groups \n \nVariable Dienogest (n=50) LNG-IUS (n=50) p value \nAge (years) 37.36 ± 5.66 38.36 ± 5.04 0.353 \nBMI (kg/m²) 23.96 ± 3.20 24.80 ± 3.93 0.245 \nParity 1.32 ± 1.02 1.70 ± 1.13 0.080 \nSymptom duration (months) 17.36 ± 7.29 18.12 ± 7.08 0.598 \nUterine size (weeks) 9.88 ± 1.81 9.76 ± 1.96 0.752 \nHemoglobin (g/dL) 10.19 ± 1.15 10.37 ± 1.11 0.427 \nBaseline dysmenorrhea VAS 7.08 ± 1.55 7.20 ± 1.55 0.700 \nBaseline chronic pelvic pain VAS 5.78 ± 1.82 6.32 ± 1.35 0.095 \nBaseline PBAC score 251.90 ± 63.78 229.18 ± 62.27 0.075 \nBaseline uterine volume (mL) 184.10 ± 52.25 192.58 ± 51.82 0.417 \nBaseline JZ thickness (mm) 15.28 ± 2.71 15.04 ± 2.41 0.644 \nAdenomyosis type: Diffuse 36 (72.0%) 37 (74.0%) 1.000 \nAdenomyosis type: Focal 14 (28.0%) 13 (26.0%) 1.000 \n \nPain outcomes \nBoth treatment groups demonstrated progressive reduction in \npain scores during follow -up. Dysmenorrhea and chronic pelvic \npain improved significantly within each group across serial visits \n(both within -group p<0.001). Between -group comparison \nshowed a greater 12 -month reduction in dysmenorrhea visual \nanalogue scale (VAS) score in the dienogest group than in the \nLNG-IUS group (between -group change p=0.010), whereas \nreduction in chronic pelvic pain was similar between groups \n(p=0.458) (Table 2 and Table 2b). Figure 1 illustrates the decline \nin mean dysmenorrhea VAS over time in both treatment arms. \n \nTable 2: Comparison of pain outcomes between groups over follow-up Values are mean ± SD. Between-group p values compare Dienogest versus \nLNG-IUS at each time point. \n \nOutcome Time point Dienogest (n=50) LNG-IUS (n=50) Between-group p value \nDysmenorrhea VAS Baseline 7.08 ± 1.55 7.20 ± 1.55 0.700 \nDysmenorrhea VAS 3 months 5.16 ± 1.57 5.56 ± 1.66 0.218 \nDysmenorrhea VAS 6 months 3.64 ± 1.68 4.32 ± 1.82 0.055 \nDysmenorrhea VAS 12 months 2.54 ± 1.68 3.20 ± 1.84 0.064 \nChronic pelvic pain VAS Baseline 5.78 ± 1.82 6.32 ± 1.35 0.095 \nChronic pelvic pain VAS 3 months 4.50 ± 1.73 5.04 ± 1.44 0.093 \nChronic pelvic pain VAS 6 months 3.66 ± 1.81 4.16 ± 1.52 0.138 \nChronic pelvic pain VAS 12 months 2.62 ± 2.00 3.32 ± 1.67 0.061 \nNote: Follow-up outcomes were analyzed on a per-protocol basis; denominators at each time point reflect participants who remained on assigned \ntreatment and had evaluable data. \n \nAdditional statistics for pain outcomes \nWithin-group p values are from repeated -measures ANOVA \nacross all visits; change p compares baseline -to-12-month \nimprovement between groups. \n \nOutcome Within-group p (Dienogest) Within-group p (LNG-IUS) Between-group p for 12-month \nchange \nDysmenorrhea VAS <0.001 <0.001 0.010 \nChronic pelvic pain VAS <0.001 <0.001 0.458 \n \n \n \nFig 1 Trend in mean dysmenorrhea VAS score during follow-up in the dienogest and LNG-IUS groups. \n\nInternational Journal of Clinical Obstetrics and Gynaecology https://www.gynaecologyjournal.com \n~ 898 ~ \nMenstrual blood loss outcomes \nMenstrual blood loss, assessed by pictorial blood loss \nassessment chart (PBAC) score, decreased significantly over \ntime in both groups (within -group p<0.001 for each). However, \nthe LNG -IUS group showed significantly greater improvement \nthan the dienogest group from as early as 3 months, and this \nadvantage widened by 6 and 12 months. At 12 months, the \nbetween-group difference in PBAC score was highly significant \n(p<0.001), and the change from baseline also favored LNG -IUS \n(p=0.001). Marked menstrual blood loss response at 12 months \nwas more frequent with LNG -IUS than with dienogest (82.0% \nvs 48.0%, p=0.002) (Table 3, Table 3b, and Table 3c). Figure 2 \ndepicts the trend in mean PBAC score over follow -up in both \ngroups. \n \nTable 3: Comparison of menstrual blood loss outcomes between groups over follow-up \n \nOutcome Time point Dienogest (n=50) LNG-IUS (n=50) Between-group p value \nPBAC score Baseline 251.90 ± 63.78 229.18 ± 62.27 0.075 \nPBAC score 3 months 205.70 ± 64.45 171.40 ± 58.10 0.006 \nPBAC score 6 months 166.86 ± 66.96 122.70 ± 56.56 <0.001 \nPBAC score 12 months 128.86 ± 71.39 75.32 ± 64.02 <0.001 \n \nTable 3b: Menstrual blood loss response at 12 months \n \nOutcome Dienogest (n=50) LNG-IUS (n=50) Between-group p value \nMBL response at 12 months: Marked 24 (48.0%) 41 (82.0%) 0.002 \nMBL response at 12 months: Moderate 22 (44.0%) 7 (14.0%)  \nMBL response at 12 months: Minimal 4 (8.0%) 2 (4.0%)  \n \nAdditional statistics for menstrual blood loss outcomes \n \nOutcome Within-group p (Dienogest) Within-group p (LNG-IUS) Between-group p for 12-month change \nPBAC score <0.001 <0.001 0.001 \nMenstrual blood loss response at 12 months   0.002 \n \n \n \nFig 2: Trend in mean PBAC score during follow-up in the dienogest and LNG-IUS groups. \n \nUltrasonographic outcomes \nUltrasonographic follow -up showed significant reduction in \nuterine volume and junctional zone thickness in both groups \nover time (all within -group p<0.001). The reduction in uterine \nvolume numerically favored LNG -IUS but did not reach \nstatistical significance at 12 months (between -group change \np=0.063). In contrast, reduction in junctional zone thickness was \nsignificantly greater in the LNG -IUS group at 12 months \n(between-group change p=0.002), indicating superior \nultrasonographic regression of adenomyotic changes with LNG -\nIUS for this parameter (Table 4 and Table 4b). \n \nTable 4: Comparison of ultrasonographic outcomes between groups \n \nOutcome Time point Dienogest (n=50) LNG-IUS (n=50) Between-group p value \nUterine volume (mL) Baseline 184.10 ± 52.25 192.58 ± 51.82 0.417 \nUterine volume (mL) 6 months 166.30 ± 52.43 170.66 ± 51.19 0.675 \nUterine volume (mL) 12 months 152.14 ± 53.43 154.08 ± 52.42 0.855 \nJunctional zone thickness (mm) Baseline 15.28 ± 2.71 15.04 ± 2.41 0.644 \nJunctional zone thickness (mm) 6 months 13.94 ± 2.80 13.27 ± 2.36 0.193 \nJunctional zone thickness (mm) 12 months 12.83 ± 2.85 11.95 ± 2.38 0.099 \n \n\nInternational Journal of Clinical Obstetrics and Gynaecology https://www.gynaecologyjournal.com \n~ 899 ~ \nAdditional statistics for ultrasonographic outcomes \n \nOutcome Within-group p (Dienogest) Within-group p (LNG-IUS) Between-group p for 12-month change \nUterine volume <0.001 <0.001 0.063 \nJunctional zone thickness <0.001 <0.001 0.002 \n \nAdverse effects and treatment tolerability \nThe overall adverse -effect profile differed between the two \nmodalities. Rates of irregular spotting were similar in both \ngroups, while amenorrhea was more frequent with LNG -IUS \nand weight gain and acne were numerically more common with \ndienogest, although these differences were not statistically \nsignificant. Device expulsion occurred only in the LNG -IUS \ngroup. Treatment discontinuation or removal was significantly \nmore frequent in the LNG -IUS group than in the dienogest \ngroup (32.0% vs 4.0%, p<0.001), suggesting lower tolerability \nor acceptability of LNG-IUS in a subset of patients (Table 5). \n \nTable 5: Comparison of adverse effects between treatment groups \n \nAdverse effect Dienogest (n=50) LNG-IUS (n=50) p value \nIrregular spotting 21 (42.0%) 20 (40.0%) 1.000 \nAmenorrhea 8 (16.0%) 17 (34.0%) 0.065 \nWeight gain 7 (14.0%) 3 (6.0%) 0.317 \nHeadache 5 (10.0%) 5 (10.0%) 1.000 \nAcne 5 (10.0%) 1 (2.0%) 0.204 \nDevice expulsion 0 (0.0%) 4 (8.0%) 0.117 \nTreatment discontinuation/removal 2 (4.0%) 16 (32.0%) <0.001 \nPregnancy during follow-up 0 (0.0%) 0 (0.0%)  \n \nOverall clinical response at 12 months \nAt 12 months, pain response was favorable in both groups, with \na higher proportion of marked pain response in the dienogest \narm, although the difference was not statistically significant \n(84.0% vs 72.0%, p=0.266). In contrast, menstrual blood loss \nresponse clearly favored LNG -IUS, with a significantly higher \nproportion of marked responders (82.0% vs 48.0%, p=0.002). \nOverall clinical response was good in 46.0% of the dienogest \ngroup and 60.0% of the LNG -IUS group, without a statistically \nsignificant between-group difference (p=0.229) (Table 6). \n \nTable 6: Clinical response categories at 12 months \n \nOutcome Dienogest (n=50) LNG-IUS (n=50) p value \nPain response at 12 months: Marked 42 (84.0%) 36 (72.0%) 0.266 \nPain response at 12 months: Minimal 0 (0.0%) 1 (2.0%)  \nPain response at 12 months: Moderate 8 (16.0%) 13 (26.0%)  \nMenstrual blood loss response at 12 months: Marked 24 (48.0%) 41 (82.0%) 0.002 \nMenstrual blood loss response at 12 months: Minimal 4 (8.0%) 2 (4.0%)  \nMenstrual blood loss response at 12 months: Moderate 22 (44.0%) 7 (14.0%)  \nOverall clinical response at 12 months: Good 23 (46.0%) 30 (60.0%) 0.229 \nOverall clinical response at 12 months: Partial 27 (54.0%) 20 (40.0%)  \n \nSummary of findings  \nIn relation to the primary objectives of the trial, both dienogest \nand LNG -IUS were effective in controlling symptoms of \nadenomyosis over 12 months. Dienogest demonstrated better \nreduction in dysmenorrhea, whereas LNG -IUS was more \neffective in reducing menstrual blood loss and junctional zone \nthickness on ultrasonography. Adverse -effect patterns differed \nbetween the two modalities, and treatment discontinuation or \nremoval was more common with LNG-IUS. \n \nDiscussion \nIn this randomized controlled trial, both dienogest and the \nlevonorgestrel-releasing intrauterine system (LNG -IUS) were \neffective in improving the major symptoms of adenomyosis over \n12 months of treatment. However, the pattern of benefit differed \nbetween the two modalities. Dienogest produced greater \nimprovement in pain -related outcomes, whereas LNG -IUS \nshowed a stronger effect on menstrual blood loss and somewhat \ngreater ultrasonographic regression. The adverse -effect profile \nalso differed between the groups, emphasizing that treatment \nselection in adenomyosis should be individualized according to \nthe dominant symptom and the patient’s tolerance for specific \nside effects. \nThe superior pain control observed with dienogest in the present \nstudy is consistent with the known role of progestins in \nsuppressing inflammation, reducing local estrogenic activity, \nand alleviating adenomyosis -associated dysmenorrhea [11]. \nRecent pooled evidence further supports this finding. In an in -\ndepth meta-analysis of 14 studies involving 637 patients, Lin et \nal. reported that dienogest significantly improved dysmenorrhea, \nwith a mean reduction of approximately 6 points on a 10 -point \nvisual analog scal e; the magnitude of benefit was greater in \nwomen with more severe baseline pain and with longer \ntreatment duration [8]. Similarly, long-term prospective data from \nOsuga et al. demonstrated progressive reduction in pain severity \nduring 52 weeks of dienogest therapy, with mean pain score \nchanges of −3.4 at 24 weeks and −3.8 at 52 weeks [15]. Hirata et \nal. also showed that dienogest significantly reduced \nadenomyosis-associated pelvic pain in a pilot study, supporting \nits role as an effective medical option for  symptomatic disease \n[16]. Against this background, the greater reduction in pain scores \nseen in the dienogest arm of the present study appears clinically \nplausible and is in line with the available literature [8, 15, 16]. \nWith respect to menstrual blood loss, the present study found \ngreater improvement in the LNG-IUS group. This observation is \nsupported by prior evidence showing that intrauterine \n\nInternational Journal of Clinical Obstetrics and Gynaecology https://www.gynaecologyjournal.com \n~ 900 ~ \nlevonorgestrel is particularly effective in controlling \nadenomyosis-associated heavy menstrual bleeding. In one of the \nearlier prospective studies, Fedele et al . reported marked and \nsafe relief from adenomyosis -associated menorrhagia after \nLNG-IUS insertion, with improvement in menstrual pattern and \nsignificant increases in hemoglobin, hematocrit, and ferritin \nduring follow-up [9]. Review evidence has similarly emphasized \nthat LNG -IUS is extremely effective in resolving abnormal \nuterine bleeding and can also reduce uterine volume during \nlong-term management [11]. In contrast, although dienogest is \neffective for pain, bleeding-related adverse events are frequently \nencountered during treatment. Kobayashi noted that abnormal \nuterine bleeding is the most common adverse event associated \nwith dienogest and may be particularly relevant in women with \ndiffuse disease, advanced reproductive age, severe \ndysmenorrhea, elevated CA125, or low hemoglobin levels [14]. \nAccordingly, the stronger reduction in menstrual blood loss in \nthe LNG -IUS arm in the present study is concordant with the \nbroader clinical literature [9, 11, 14]. \nThe comparative pattern seen in the current trial also mirrors the \nresults of controlled comparative studies. Ota et al ., in a \ncontrolled clinical trial of 157 women with adenomyosis, found \nthat both LNG -IUS and dienogest reduced pain scores, but \ndienogest offered greater efficacy for pain control at 3 months, \nwhile patterns of bleeding differed between the groups over \nlonger follow-up [10]. In that study, the days of bleeding after 12 \nmonths were significantly decreased with dienogest compared \nwith LNG -IUS [10]. This point deserves careful interpretation \nwhen comparing across studies. The present study assessed \nmenstrual blood loss rather than only duration of bleeding, and \nour findings suggest that LNG -IUS provided superior control of \nblood loss burden. This distinction is important because amount \nof bleeding and number of bleeding days are not interchangeable \nclinical endpoints, particularly in adenomyosis where irregular \nspotting and altered bleeding patterns may coexist. The recent \nreview by Habiba et al . also highlighted that the relationship \nbetween adenomyosis and abnormal uterine bleeding remains \nmethodologically difficult to characterize because of \nheterogeneity in diagnostic criteria, inconsistent measurement of \nblood loss, and frequent coexistence of other gynecologic \nconditions [12]. Thus, differences between studies may reflect \nvariation in endpoint definition as much as variation in treatment \neffect [10, 12]. \nThe ultrasonographic findings in the present study add a further \ndimension to treatment comparison. Both groups demonstrated \nimprovement in imaging parameters during follow-up, but LNG-\nIUS showed somewhat greater regression in sonographic disease \nburden. This is compatible with existing reviews suggesting that \nLNG-IUS may reduce uterine volume in the longer term [11]. Ota \net al. observed that reduction in whole uterine body volume after \ntreatment was transient in different adenomyosis subtypes, \nindicating that imaging regression may occur but may not \nalways parallel sustained symptom relief [10]. For this reason, the \nultrasonographic advantage of LNG -IUS in the present study \nshould be interpreted as supportive rather than decisive; \nsymptom control remains the central therapeutic goal, and \nimaging change should be considered alongside clinical \nimprovement rather than in isolation. \nAdverse effects differed meaningfully between the two \ntreatment groups in the present study. The dienogest arm showed \na pattern consistent with known progestin -related bleeding \ndisturbances, whereas the LNG-IUS arm was characterized more \nby device-related events such as expulsion, removal, or irregular \nbleeding after insertion. This again reflects prior literature. \nKobayashi’s review emphasized that bleeding -related adverse \nevents are highly characteristic of dienogest therapy [14]. Osuga \net al. reported metrorrhagia in 96.9% of women receiving long -\nterm dienogest, although most events were tolerable and serious \nadverse events were not observed [15]. Hirata et al . similarly \nfound that worsening anemia due to metrorrhagia occurred in \nsome patients during dienogest treatment [16]. On the other hand, \nFedele et al. documented both expulsion and elective removal of \nLNG-IUS in women treated for adenomyosis -associated \nmenorrhagia [9]. Therefore, the adverse -event differences \nobserved in the present study are consistent with established \nexperience and highlight the practical importance of counselling \npatients about expected treatment -specific side effects before \ninitiation [9, 14-16]. \nFrom a clinical standpoint, the present findings support a \nsymptom-oriented approach to medical management of \nadenomyosis. Review articles have stressed that there is no \nuniversally accepted guideline -endorsed single best medical \ntreatment for all patients with adenomyosis, and treatment \ndecisions should instead be guided by symptom profile, \nreproductive plans, uterine characteristics, and tolerance of \nadverse events [11]. When dysmenorrhea and chronic pelvic pain \nare dominant, dienogest may be especially attractive because of \nits consistent analgesic benefit [8,14 -16]. Conversely, when \nheavy menstrual bleeding is the leading complaint, LNG -IUS \nmay offer better control and the added advantage of local \ntherapy with less systemic exposure [9,11]. The current trial \ntherefore reinforces the principle that the two therapies should \nnot be viewed as directly interchangeable in all patients, but \nrather as options with overlapping yet distinct strengths. \nThe present study should also be viewed in the context of \nemerging and alternative conservative therapies for \nadenomyosis. High -intensity focused ultrasound (HIFU), for \nexample, has shown promising results in reducing dysmenorrhea \nand uterine volume, with meta -analytic evidence suggesting \nimprovement in symptoms and quality of life after treatment [13]. \nHowever, the current evidence base for HIFU is limited by \nnonuniform studies and the absence of comparative randomized \ntrials against standard conservative therapies [13]. In contrast, \nboth dienogest and LNG -IUS already have a stronger practical \nfooting in routine care, and the comparison between them \nremains clinically relevant because many patients require long -\nterm symptom control while wishing to avoid hysterectomy. \nCertain limitations should be considered while interpreting the \npresent findings. First, the follow -up duration of 12 months is \nadequate for assessing short -term and medium -term response, \nbut it does not address longer-term durability, continuation rates, \nor recurrence after discontinuation. Second, ultrasonographic \nchange, although useful, may not fully capture disease burden or \ncorrelate perfectly with symptoms. Third, bleeding outcomes in \nadenomyosis remain intrinsically difficult to standardize across \nstudies, as emphasized in recent review literature [12]. \nNevertheless, the randomized comparative design and the \nparallel assessment of pain, menstrual blood loss, imaging \nresponse, and adverse effects strengthen the clinical relevance of \nthe present analysis. \nIn conclusion, both dienogest and LNG -IUS were effective in \nthe symptom control of adenomyosis, but they differed in their \ndominant areas of benefit. Dienogest was more effective for pain \nrelief, whereas LNG -IUS provided better control of menstrual \nblood loss and somewhat greater ultrasonographic improvement. \nThe adverse -effect patterns also differed substantially between \nthe modalities. These findings support individualized treatment \nselection based on the patient’s predominant sympto m complex, \n\nInternational Journal of Clinical Obstetrics and Gynaecology https://www.gynaecologyjournal.com \n~ 901 ~ \nimaging findings, and tolerance of treatment-related side effects. \nFurther larger comparative studies with longer follow -up are \nwarranted to clarify long -term continuation, recurrence patterns, \nand the optimal sequencing of conservative therapies in \nadenomyosis [8, 10, 12, 14]. \n \nReferences: \n1. Guo SW. Cracking the enigma of adenomyosis: an update \non its pathogenesis and pathophysiology. Reproduction. \n2022;164(5):R101-R121. \n2. Bourdon M, Santulli P, Marcellin L, Maignien C, Maitrot -\nMantelet L, Bordonne C, et al . Adenomyosis: an update \nregarding its diagnosis and clinical features. J Gynecol \nObstet Hum Reprod. 2021;50(10):102228. \n3. Farquhar C, Brosens I. Medical and surgical management of \nadenomyosis. Best Pract Res Clin Obstet Gynaecol. \n2006;20(4):603-616. \n4. Akhigbe RE, Afolabi OA, Adegbola CA, Akhigbe TM, \nOyedokun PA. Comparison of the effectiveness of \nlevonorgestrel intrauterine system and dienogest in the \nmanagement of adenomyosis: A systematic review and \nmeta-analysis. Eur J Obstet Gynecol Reprod Biol. \n2024;300:230-239. \n5. Ozdegirmenci O, Kayikcioglu F, Akgul MA, Kaplan M, \nKarcaaltincaba M, Haberal A, et al . Comparison of \nlevonorgestrel intrauterine system versus hysterectomy on \nefficacy and quality of life in patients with adenomyosis. \nFertil Steril. 2011;95(2):497-502. \n6. Krentel H, De Wilde RL. Prevalence of adenomyosis in \nwomen undergoing hysterectomy for abnormal uterine \nbleeding, pelvic pain or uterine prolapse: A retrospective \ncohort study. Ann Med Surg (Lond). 2022;78:103809. \n7. Stratopoulou CA, Donnez J, Dolmans MM. Conservative \nmanagement of uterine adenomyosis: medical vs. surgical \napproach. J Clin Med. 2021;10(21):4878. \n8. Lin S, Chen Y, Yi J, Xie X, Liu X, Guo SW. Dienogest \ntreatment of symptomatic adenomyosis: An in -depth meta-\nanalysis. Eur J Obstet Gynecol Reprod Biol. 2025;305:365 -\n374. \n9. Fedele L, Bianchi S, Raffaelli R, Portuese A, Dorta M. \nTreatment of adenomyosis -associated menorrhagia with a \nlevonorgestrel-releasing intrauterine device. Fertil Steril. \n1997;68(3):426-429. \n10. Ota I, Taniguchi F, Ota Y, Nagata H, Wada I, Nakaso T, et \nal. A controlled clinical trial comparing potent progestins, \nLNG-IUS and dienogest, for the treatment of women with \nadenomyosis. Reprod Med Biol. 2021;20(4):427-434. \n11. Vannuccini S, Luisi S, Tosti C, Sorbi F, Petraglia F. Role of \nmedical therapy in the management of uterine adenomyosis. \nFertil Steril. 2018;109(3):398-405. \n12. Habiba M, Guo SW, Benagiano G. Adenomyosis and \nabnormal uterine bleeding: review of the evidence. \nBiomolecules. 2024;14(6):616. \n13. Marques ALS, Andres MP, Kho RM, Abrao MS. Is high -\nintensity focused ultrasound effective for the treatment of \nadenomyosis? A systematic review and meta -analysis. J \nMinim Invasive Gynecol. 2020;27(2):332-343. \n14. Kobayashi H. Efficacy, adverse events, and challenges of \ndienogest in the management of symptomatic adenomyosis: \na comparison with different hormonal treatments. Gynecol \nObstet Invest. 2023;88(2):71-80. \n15. Osuga Y, Watanabe M, Hagino A. Long -term use of \ndienogest in the treatment of painful symptoms in \nadenomyosis. J Obstet Gynaecol Res. 2017;43(9):1441 -\n1448. \n16. Hirata T, Izumi G, Takamura M, Saito A, Nakazawa A, \nHarada M, et al. Efficacy of dienogest in the treatment of \nsymptomatic adenomyosis: a pilot study. Gynecol \nEndocrinol. 2014;30(10):726-729. \n \nHow to Cite This Article \nDas S, Das B, Patra KK.  Comparative efficacy of dienogest versus \nlevonorgestrel-releasing intrauterine system in the symptom control of \nadenomyosis: A randomized controlled trial . International Journal of \nClinical Obstetrics and Gynaecology. 2026;10(2): 894-901.  \n \n \nCreative Commons (CC) License \nThis is an open access journal, and articles are distributed under the terms \nof the Creative Commons Attribution -Non Commercial-Share Alike 4.0 \nInternational (CC BY -NC-SA 4.0) License, which allows others to remix, \ntweak, and build upon the work non -commercially, as long as appropriate \ncredit is given and the new creations are licensed under the identical terms.","source_license":"CC0","license_restricted":false}