Prevalence and Use of Complementary Health Approaches among Women with Chronic Pelvic Pain in a Prospective Cohort Study

Chronic pelvic pain (CPP) is defined as continuous or episodic pain in the lower abdomen or pelvis lasting at least six months [ 1 ]. With an estimated prevalence ranging from 12-39% [ 2 - 5 ], CPP is among the most common pain conditions experienced by women. In addition to the burden of physical discomfort, unrelieved CPP exacts a range of individual costs, including compromised quality of life, impaired function, and increased likelihood of psychological morbidity [ 6 , 7 ]. CPP is also associated with substantial societal-level costs, with estimated annual costs of treatments and lost productivity exceeding $2 billion [ 4 , 8 ]. The impact of CPP is exacerbated by the limited effective treatment choices currently available. A recent systematic review of the comparative effectiveness of therapies for CPP found insufficient evidence for common surgical (e.g., hysterectomy, laparoscopic uterosacral nerve ablation) and non-surgical approaches (e.g., hormonal therapies) [ 9 ]. Nonhormonal and nonpharmacologic treatments, such as physiotherapy or behavioral and integrated management approaches, seem beneficial but have not been adequately studied [ 9 , 10 ]. To address the complex range of physical and psychosocial symptoms associated with CPP, recommended care emphasizes improving day-to-day pain management, functioning, and quality of life through multidisciplinary and holistic approaches [ 11 - 16 ]. Elements of integrative medicine – such as using a broad array of therapeutic approaches informed by evidence, emphasizing the practitioner-patient relationship, and focusing on the whole person [ 17 ] – are well aligned with guidelines for optimal care for women with CPP [ 18 ]. Health practices outside of mainstream conventional medicine, such as herbal medicine and acupuncture, are a key component of integrative medicine. We refer to these practices as complementary health approaches , the term preferred by the National Center Complementary and Alternative Medicine [ 19 ]. The use of complementary health approaches is common for pain conditions. An estimated 35-52% of patients with chronic pain use therapies such as vitamins and mineral supplements, nutraceuticals, massage therapy or acupuncture for their symptoms [ 20 , 21 ]. Greater pain severity, longer duration of painful symptoms, and improved health-related quality of life among patients with functional limitations have been found to be associated with the use of these approaches [ 22 , 23 ]. The limited research conducted on complementary health approaches and painful pelvic conditions suggests potential therapeutic benefits. Studies of traditional Chinese medicine treatments, including Chinese herbal medicine and acupuncture, for example, have found significant improvements in pain relief for primary dysmenorrhea compared with pharmaceutical drugs [ 24 - 26 ]. And the anti-prostaglandin and anti-inflammatory effects of supplements such as ginger root and omega-3 fatty acids are known to have analgesic benefits [ 27 - 30 ]. Finally, nutritional interventions designed to increase antioxidants may improve nocioceptive, inflammatory, and neuropathic pain associated with CPP [ 31 ]. Despite widespread use in the general population and potential benefits for the symptoms of CPP, little is known about the use of complementary health approaches among women with CPP and its association with patient-centered outcomes such as health-related quality of life. Cross-sectional surveys indicate that 60% of perimenopausal women with self-reported pelvic pain [ 32 ], and 84% of women with interstitial cystitis used some form of complementary medicine [ 33 ]. These studies suggest a high usage prevalence of complementary health approaches for CPP but have limited generalizability due to sampling methodology. In this study, we sought to estimate the prevalence of use of complementary health approaches and to describe factors associated with use, including sociodemographic factors, attitudes, beliefs, and clinical factors among women with CPP. We examined the association between the use of complementary health approaches and health-related quality of life and also identified usage patterns of complementary health approaches, such as repeated use over time, specific herbs and supplements used, and types of conventional treatments also used for CPP.

We used data from the Study of Pelvic Problems, Hysterectomy, and Intervention Alternatives (SOPHIA) [ 34 , 35 ], which was designed to explore the natural history of noncancerous gynecologic conditions and to identify predictors of treatment use and health-related quality of life. SOPHIA participants included women 31-54 years of age who sought care for symptomatic fibroid tumors, abnormal bleeding, and/or pelvic pain from academic, community, and public hospital practices in the San Francisco Bay area. SOPHIA consisted of two cohorts (recruited in 1997-1998 and 2003-2004), each observed for four years. Women who enrolled in the first cohort were invited to re-enroll in the second cohort. Potential participants were excluded if they had already undergone or were planning to have a hysterectomy, if they had been diagnosed with a gynecologic malignancy, or if they had entered menopause. Questionnaires were administered by an interviewer at baseline and annually thereafter in English or Spanish. At enrollment, participants were each classified into one of five clinical categories based on symptoms and diagnoses she had received: 1) CPP only, 2) CPP and abnormal uterine bleeding, 3) abnormal uterine bleeding, 4) abnormal uterine bleeding with fibroids 5) pelvic pressure with fibroids. All SOPHIA participants were asked at each follow up assessment if they had pelvic pain and, if they did, how long they had been experiencing this symptom. For this analysis, we defined our subset of women with CPP on the basis of commonly accepted definitions of CPP [ 1 , 36 ] and prior research [ 37 ]. We included participants from the second cohort of SOPHIA who indicated pain below the umbilicus for at least 6 months either: (1) during the recruitment interview or (2) during one of the annual follow-up questionnaires (see Figure 1 ). For those participants identified with CPP after study enrollment (i.e., during one of the annual questionnaires), we defined their baseline time point as the survey administered when they first reported CPP. Our primary outcome was the use of complementary health approaches. At baseline, participants were asked if they had ever tried acupuncture, herbs, vitamins or minerals, special foods or diet, or physical exercise for control of their pelvic problems. The survey language refers broadly to pelvic problems for two reasons: (1) SOPHIA participants included women with pain, bleeding and/or fibroids and (2) many treatments for one symptom also control other symptoms. Annual surveys conducted during the four-year follow-up period asked about use of these treatments in the prior year. We created a dichotomous measure for past year use of complementary health approaches (yes = used acupuncture, herbs, vitamins or minerals, or special foods or diet, no= did not use acupuncture, herbs, vitamins or minerals, special foods or diet). We excluded physical exercise from our summary measure of the use of complementary health approaches because it included some practices typically categorized as complementary health approaches, such as yoga, but many that are not, such as jogging and swimming. Nonetheless, since physical activity is a critical component of health and an integrative approach to care, we analyzed data on physical exercise separately. We assessed the use of physical exercise and of each complementary health approach by demographic and clinical characteristics. Perceived effectiveness and any side effects experienced from these health practices were also ascertained. Based on prior research of patient-centered factors associated with CPP and treatment seeking behavior, we examined symptom resolution [ 34 ], health-related quality of life [ 6 ], and depression [ 7 ]. Symptom resolution was measured using a single item: “To what extent would you say your pelvic problems have been resolved?” with four possible responses (not at all, somewhat, mostly, or completely resolved). Participants were instructed that “pelvic problems” include bleeding, fibroids, pressure, pain, or prolapse. Although this item measures resolution of symptoms in general and not solely pain, prior evidence indicates that degree of symptom resolution is a strong predictor of subsequent treatment choices for women with pelvic problems [ 38 ]. We used the following condition-specific and generic health-related quality of life measures. For the Pelvic Problem Impact Questionnaire [ 34 ], respondents completed questions on “how much your pelvic problems overall, or any treatments you received for those problems, interfered with the following things during the past 4 weeks”. Interference with twelve domains, including mood, ability to exercise, sleep, and social relationships, were rated using a 5-point Likert scale from ‘not at all’ to ‘a great deal’. All 12 items were transformed to a scale of 0-100 and averaged for an overall Pelvic Problem Impact score. In the full SOPHIA sample, Pelvic Problem Impact had an overall mean of 33, a standard deviation of 24, and internal consistency reliability of 0.94 [ 34 ]. We also assessed the physical and mental component summary scales from the Medical Outcomes Study SF-12 questionnaire [ 39 ]. Each of these measures was transformed to 0-100 scales with 100 indicating optimal functioning. As a measure of depressive symptoms, we used the Patient Health Questionnaire-2 (PHQ-2) the short form of the Primary Care Evaluation of Mental Disorders screening instrument [ 40 ]. The PHQ-2 has two items scored 0 to 3 that are summed for a total score of 0-6. Using the scoring algorithm for the PHQ-2, participants were classified as having no depressive symptoms, major depressive symptoms, or other depressive symptoms. Attitudes and beliefs are predictors of health behaviors such as choice of treatments for CPP [ 34 ] and use of complementary health approaches [ 41 ]. For instance, wanting a natural approach to treatment is a primary reason women choose to use complementary health approaches [ 42 ]. For this study, attitudes and beliefs were assessed based on participants’ agreement with statements pertaining to: (1) “Benefits of Not Having a Uterus,” consisting of three items (“menstruation is one of the downsides of being a woman,” “the uterus is useless to women who have completed childbearing,” “if I had a hysterectomy I would feel happy not to have to worry about birth control”); (2) “Hysterectomy Concerns,” consisting of three statements about feeling older, violated, and sad about losing one’s fertility if one had a hysterectomy; and (3) “Value of Uterus,” which included two statements about the perceived importance of having a uterus for sexual enjoyment and its role in feeling complete as a woman. For each item, participants indicated their level of agreement using a 7-point response (1 = strongly disagree to 7 = strongly agree). The three scales were then created using an unweighted average of the responses to the individual items. The identification of these themes from focus groups, and subsequent factor analysis were previously reported [ 34 , 35 ]. Using data from annual follow-up surveys, we examined patterns of use, such as frequency of complementary health approaches and whether there were differences in conventional healthcare practices used by women who used complementary health approaches. We calculated the number of times the use of complementary health approaches was reported as a percentage of interviews completed. Conventional treatments included whether women had had a hysterectomy during the study observation period, ever had an oophorectomy, or other surgical procedures (dilation and curettage, polyp removal, surgical endometriosis); used gonadotropin-releasing hormone (GnRH) agonist therapy, oral contraceptives, opioids, or other medications. Descriptive data on socio-demographic variables were collected at baseline, including age, race, ethnicity, education, income, and occupational prestige, which was based on mapping participants’ own or partner’s occupation to associated prestige scores from the 1989 National Opinion Research Center General Social Survey [ 43 ]. Among the subset of women with CPP, we calculated descriptive statistics, including means, standard deviations, and percentages for baseline data. We used t-tests and chi-square tests to assess statistically significant differences, defined as p < 0.05, between women who used complementary health approaches and those who did not. Unadjusted and adjusted odds ratios of use of complementary health approaches were estimated via logistic regression analyses. Variables in unadjusted and adjusted models included sociodemographic, clinical, and other variables that we hypothesized were associated with use of complementary health approaches, symptoms of CPP or both based on existing literature [ 22 , 23 , 44 ]. For adjusted analyses, our initial model included all variables included in unadjusted analyses. We used a backward elimination procedure to remove nonsignificant explanatory variables (p > 0.20) from the multivariable adjusted model [ 45 ]. Categorical variables, such as race/ethnicity, were considered together as a group.

From the second cohort of SOPHIA (n= 741), we created a subset of 701 participants who were classified as having CPP, including 610 women identified from the baseline survey and 91 women identified in one of the subsequent annual surveys. Women who had missing responses for two or more complementary health approaches were excluded from analysis (n=2). Thus, the analytic data set included 699 participants with CPP (94% of second cohort of SOPHIA) and sufficient data on their use of complementary health approaches. The mean age of these participants was 43.2 years; 41.0% of the women were white; 27.4% were African American; 18.5% were Latina; and 8.1% were Asian ( Table 1 ). Over one-quarter of the women (27.8%) were foreign born and just over one-half were married or living with a partner. Approximately one-half of the women were college graduates, and two-thirds had an annual household income of less than $50,000. Slightly over one-half of women with CPP (50.9%) reported having used at least one complementary health approach in the past year at baseline. These women did not differ from non-users by age, race/ethnicity, marital status, birthplace, household income, education, or recruitment site. A higher proportion of Spanish speakers reported use of complementary health approaches compared with English speakers (63.2% vs. 49.8%, p= 0.05). Compared with non-users, women who used complementary health approaches had more optimal health-related quality of life at baseline as measured by the Pelvic Problem Impact Questionnaire (25.6 vs. 31.6, p<0.001). Average SF-12 Physical Component Summary scores were slightly lower for women who had used complementary health approaches compared with non-users (44.0 vs. 45.6, p < 0.05), but no association was observed on the SF-12 Mental Component Summary or symptoms of depression. In addition, complementary health approaches use/non-use did not differentiate women with respect to their attitudes or belief scores. In multivariable analysis, clinical factors independently and significantly associated with the use of complementary health approaches included having heavy bleeding with fibroids, some degree of pelvic problem resolution, and more optimal pelvic problem impact scores ( Table 2 ). In addition, higher educational attainment and Spanish primary language were independently associated with use of complementary health approaches in analyses that adjusted for symptoms at screening, symptom resolution, and health related quality of life. Compared with non-users, users of complementary health approaches were more likely to have a hysterectomy during the four-year study observation period (7.0% vs. 11.5%, p < 0.05), though this association was attenuated and no longer significant when adjusting for age, education, income, and baseline symptoms. Users of complementary health approaches were also more likely to ever have had an oophorectomy (0 vs. 1.4%, p < 0.05), or to use GNRH agonists (9.0% vs. 15.2%, p<0.01) or opioids (42.9% vs. 50.3%, p< 0.05). Other surgical procedures (i.e., dilation and curettage, polyp removal, surgical endometriosis) followed a similar trend with users of complementary health approaches being more likely to have had these procedures compared with non-users. Nonsteroidal anti-inflammatory drugs (NSAIDs) were commonly used among all women with CPP (93.3%) regardless of their use of complementary health approaches ( Table 3 ). Based on longitudinal survey data collected annually, 22.6% of women with CPP never used complementary health approaches during the four year time period of the study. One-third reported using complementary health approaches 25-50% of the interviews. A substantial proportion of women in the study (44.8%) reported use of complementary health approaches during more than half of the survey time periods, including 180 women (25.8%) who reported use at every interview during the study (data not shown). Among women with CPP, 8.2% used acupuncture; 21.6% used special foods or diets; 26.9% used herbs; 28.7% used vitamins and minerals; and 38.3% used physical exercise in the past year ( Table 4 ). Those who used acupuncture were more likely to be non-Hispanic white and of higher socioeconomic status as measured by education, income, and occupational prestige. Among women who used vitamins and minerals, most reported using iron (46.5%) or calcium (14.0%). Women who used herbs were more likely to be foreign-born and speak Spanish as their primary language compared to those who did not use herbs. Herbs most commonly reported included Chinese herbs (24.5%), chamomile (16.5%), and evening primrose oil (8.0%). Dietary approaches included increasing fruits and vegetables (21.9%), decreasing caffeine (18.5%), decreasing carbohydrates and sugars (18.5%). Physical exercise included Kegels (19.9%), aerobic exercise (56.2%) and yoga (18.4%). Most women who used acupuncture (91%) had at least some improvement in symptoms based on self-report and were not at all bothered by the side effects of acupuncture treatments (96%). Similarly, women who used special foods or diets (82.5%) or herbs (84.9%), noted that their symptoms were a little or a lot better from the complementary health approaches they used; and that they were not at all bothered by side effects (91.2% for special foods or diet and 95.7% for herbs). Relative to other complementary health approaches, fewer women reported that their symptoms improved from vitamin use (63.3%); and 85.8% were not at all bothered by side effects (see Table 5 ).

This is the first study, to our knowledge, to examine the use of complementary health approaches among a cohort of women with CPP. Consistent with prior research on chronic pain [ 20 , 21 , 46 ], and among women with pelvic-related conditions [ 32 , 33 ], we found that the use of complementary health approaches for CPP is quite common, with half of the women in our cohort using at least one modality in the previous year. Moreover, longitudinal data from the study indicate that about one-quarter of women consistently use complementary health approaches, reporting use at every interview over a period of up to four years. Compared with non-users, women who used complementary health approaches were more, not less, likely to use conventional surgical and pharmaceutical approaches for their pelvic problems. Combined, these findings confirm substantial interest, high prevalence, and consistent use of complementary health approaches among women with CPP, highlighting the need for a better understanding of multimodal approaches to address the complex condition of CPP. Our findings suggest that even with modest perceived benefits, women with CPP are likely to use complementary health approaches, and typically have only minimal side effects. This is particularly notable given that standard treatments used for CPP and related conditions like endometriosis are frequently discontinued because of side effects. For instance, hormonal contraceptives have an estimated discontinuation rate of 37% [ 47 ], due in large part to associated side effects such as irregular bleeding, headaches or weight gain. The long-term use of nonsteroidal anti-inflammatory drugs poses the risk of both gastrointestinal bleeding and cardiovascular disease [ 48 ], which are important considerations for women with CPP at risk for cardiovascular or peptic ulcer disease. Education for health care professionals about herbal and dietary supplements is needed given the common usage of these products and clinicians’ relatively low level of knowledge, confidence and communication about these topics [ 49 ]. Clinical considerations for providers treating patients with CPP include awareness of health practices commonly used and knowledge of the clinical effectiveness and safety of various complementary health approaches. We found that the use of natural products is clinically relevant for the care of women with CPP: one in four women in our study used herbal medicine and one in five used nutrition-related approaches. Evidence from randomized controlled trials suggests that the anti-prostaglandin and anti-inflammatory effects of some herbs and nutritional supplements provide pain relief with minimal adverse events compared with pharmaceutical drugs [ 24 , 27 - 29 , 31 ]. For example, ginger root ( Zingiber officinale rhizome) has both anti-inflammatory and anti-prostaglandin effects and has been shown to be equally as effective as NSAIDs [ 27 ] and better than placebo [ 28 ] in the treatment of dysmenorrhea. Given the relatively common use of herbal medicine and nutritional supplements in conjunction with pharmaceutical medications, expanding our knowledge base of the safety and efficacy of herb-drug combinations is an important area of research to improve care for women with CPP. We also found that women with CPP are considerably more likely to use acupuncture compared with the general U.S. population (8% in our study vs. 1% nationally) [ 44 ]. Both geographic and clinical factors are likely to contribute to the higher prevalence of acupuncture users in our study. Complementary health approaches are more common in Western regions of the U.S. and pain is a common reason for use [ 44 ]. Acupuncture studies suggest significant improvement in pain relief related to dysmenorrhea compared with NSAIDs and with sham acupuncture [ 25 , 26 ]. Significant pain relief and trends of improved health-related quality of life among women receiving acupuncture has been observed for endometriosis-related chronic pelvic pain compared with sham acupuncture, but study samples were small [ 50 ]. Moreover, acupuncture is generally accepted as a safe treatment with minimal risks such as bleeding and hematoma at the needle site [ 51 ]. Our study has a number of limitations. Our sample population included women living in the San Francisco Bay Area who receive healthcare through community, academic or public hospitals, which may limit the generalizability of our study. We used a commonly accepted definition of CPP – pain below the umbilicus for at least six months [ 36 ] – that includes a heterogeneous group of conditions such as endometriosis, pelvic inflammatory disease, and irritable bowel syndrome. But we recognize, as others have [ 1 ], that there is considerable inconsistency in how CPP is defined in research. Furthermore our reliance on participant self-report of symptoms, treatment effects on symptoms, and use of complementary health approaches may have resulted in recall bias. Additionally, some survey questions were worded generally to pertain to the range of symptoms that SOPHIA participants were experiencing, including pain, bleeding and symptomatic fibroids. The majority of women in the SOPHIA sample experienced pain as a symptom, but data were gathered about general symptoms and did not solicit information specifically about pain-related symptoms. Epidemiologic and health services research of complementary health practices usually includes a comprehensive range of natural products and mind body practices that are not typically considered to be part of conventional medicine [ 44 , 52 ]. Our study asked about select complementary health practices. The narrower range of practices included in our study may have underestimated the overall use of complementary health practices among women with CPP. Our study’s omission of mind-body practices such as meditation and imagery is an important gap to address in future research. Pilot research suggests that meditation improves daily pain scores, physical function, mental health, and social function among women with CPP [ 53 ]. Guided imagery may decrease pain and symptoms of interstitial cystitis without negative side effects [ 54 ]. Such modalities are particularly promising approaches for the treatment of central sensitization, which occurs when the central nervous system distorts or amplifies pain signals and likely plays an important causal role in chronic pain conditions [ 55 ], including vulvodynia [ 56 ], dysmenorrhea [ 57 ], and endometriosis [ 58 , 59 ]. Exercise and movement play an important therapeutic role in the treatment of chronic pain by restoring functional capacity and improving quality of life [ 60 ]. Musculoskeletal conditions affecting the low back, hip, abdomen, and pelvic floor commonly contribute to CPP [ 61 ]. Therapeutic exercise and physical activity are often used to treat musculoskeletal conditions associated with CPP. Although we asked about physical exercise in this study, we did not differentiate between participation in physical therapy, informal exercise or alternative movement therapies such as yoga and tai chi. Yoga has been found to the decrease the severity and duration of primary dysmenorrhea [ 62 ]; tai chi, though not studied in the context of CPP, has been effective for other chronic pain conditions such as low back pain [ 63 ]. Further studies differentiating the effects of various forms of physical activity on pain reduction, function and quality of life are needed. Importantly, this study describes the use of complementary health approaches among women with CPP, but we were unable to measure the effectiveness of these approaches beyond patients’ self-report of global effects on symptoms. Furthermore, our analysis focused on cross-sectional data; we did not examine the temporal relationships between women’s use of complementary and conventional health approaches or the temporal directionality of the association between health-related quality of life and use of complementary health approaches. Future clinical studies of the efficacy and effectiveness of complementary health approaches for CPP are warranted and would benefit from rigorous research methodologies that account for complex whole systems that often characterize complementary health approaches and the range of outcomes most relevant to patients including health-related quality of life [ 64 ].

The high usage prevalence of complementary health approaches in conjunction with conventional treatments raises important clinical questions about the interactive effects of multiple approaches on health outcomes among women with CPP. CPP is a complex medical condition causing both physical and psychological symptoms. Conventional therapies such as medications and surgery have limited effectiveness and in some cases, substantial side effects. More treatment modalities are needed to comprehensively address the range of health care needs of women with CPP. Complementary health approaches such as acupuncture and herbal medicine have few reported side effects and may fill a gap in the care of women with CPP; they have the potential to improve health-related quality of life and to address patient-centered outcomes. Because so many women with CPP are using complementary health approaches, clinicians are challenged to become familiar with dosing, side effects, interactions with other therapies and safety profile so that patients can be appropriately counseled regarding their use. Unfortunately, many of the complementary health approaches used by women have either not been studied or poorly studied offering minimal evidence for their efficacy. There is a tremendous need for research into complementary health approaches in the treatment of women with CPP.