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Complementary and alternative medicine use during early pregnancy

European Journal of Obstetrics & Gynecology and Reproductive Biology, pages 251 - 255

Abstract

Objective

To determine the prevalence and explore predictors of Complementary and Alternative Medicine (CAM) use during early pregnancy.

Study design

A questionnaire survey of pregnant women (500) attending for mid trimester scan at the maternity services in Grampian, North-East Scotland. Outcome measures included; CAM used; vitamins and minerals used; independent predictors of use; views and experiences. Descriptive and inferential statistical analysis.

Results

The response rate was 66%. Two thirds of respondents (63%) reported using CAM, excluding vitamins and minerals, during early pregnancy. Respondents reported using a total of 28 different CAM modalities, of which oral herbal products were the most common (37% of respondents, 25 different products). The independent predictors of CAM use identified were: use by family and friends (OR 4.1, 95% CI 2.3–7.3,p < 0.001); ethnicity (non-white British) (OR 3.4, 95% CI 1.8–6.8,p < 0.001); and use prior to pregnancy (OR 2.4, 95% CI 1.2–4.8,p = 0.014). In comparison to prescribed medicines, most users were uncertain if CAM were safer (63%), more effective (66%), free from possible adverse effects (46%) or drug-CAM interactions (50%).

Conclusions

Despite the majority of respondents being uncertain about their safety and effectiveness, CAM modalities and CAM products are widely used during the early stages of pregnancy in this study population. The role of family and friends rather than health professionals in the decision to use CAM may be of concern and requires further investigation.

Keywords: Antenatal, Complementary therapies, Herbal medicine, Pregnancy, Views and experiences.

Introduction

The World Health Organisation defines complementary and alternative medicine (CAM) as a ‘broad set of health care practices that are not part of that country's own tradition and are not integrated into the dominant health care system’ [1] . CAM approaches are diverse and include modalities such as herbal and homeopathic therapies, acupuncture, aromatherapy, Reiki, Shiatsu and yoga [2] . While few CAM approaches are supported by robust efficacy, effectiveness or safety data[3], [4], and [5]use is widespread, with women reportedly the major users both in health and disease [6] . Although CAM modalities have been used for centuries and exponents of CAM cite this as evidence of safety, there is a real lack of scientifically valid safety and efficacy data. These issues may be of a particular concern during the early stages of pregnancy and fetogenesis, a time during which several herbal products have been associated with both maternal and foetal harm[7], [8], and [9]. In the UK the precautionary approach to the use of CAM during pregnancy was reinforced in 2008 following guidance from the National Institute for Clinical Excellence (NICE Recommendation ID 195, CG62), which stated “Pregnant women should be informed that few complementary therapies have been established as being safe and effective during pregnancy. Women should not assume that such therapies are safe and they should be used as little as possible during pregnancy”.

Since 2008, over 20 surveys from Europe, the Americas, Asia, Australia and Oceania, and Africa have reported on the prevalence of CAM use by pregnant women, (10–33) as highlighted in a recent systematic review [34] . Thirteen of these studies reported on more than one CAM modality, a further nine studies focused on herbals only and the remaining two on herbals and vitamins. Reported prevalence rates ranged from 5.8% to 74.2% in two separate studies conducted in the USA[20] and [23]. This wide variation is attributed to many factors including lack of or inconsistent CAM definition, differences in culture and ethnicity, and study design. Although all studies assessed CAM use during pregnancy, only nine reported on CAM usage and stage of pregnancy[11], [12], [16], [18], [19], [22], [23], [27], [28], [29], and [30]. The link between stage of pregnancy and CAM use remains unclear, with five studies[11], [12], [19], [21], and [30]reporting highest use during the latter stages, and three highest use during the early stages of pregnancy[16], [18], and [24].

While the majority of studies quantified associations between demographic variables and CAM use during pregnancy,[11], [13], [14], [15], [16], [17], [18], [19], [20], [21], [23], [24], [25], [27], [28], [29], [30], and [31]less than half used a multivariate approach to identify independent predictors[13], [18], [23], [25], [27], [28], [29], [30], and [33]. Predictors included: use of CAM prior to pregnancy[13], [21], [28], and [33], higher educational attainment[18], [19], [21], [32], and [33], presence of chronic disease/prescribed medication[21], [25], and [29], ethnic background/nationality[14] and [21], higher income [14] and age [28] . A major limitation of the majority published studies is the use of postnatal data collection to assess CAM use throughout the whole of pregnancy. There is a lack of UK data describing CAM use during early pregnancy, and a number of reasons limiting the generalizability of published data to UK populations and practice. These include: inconsistency in CAM definition and scope of CAM, clear cultural influences on CAM use and the dynamic nature of popular CAM use. Therefore the aim of this study was to determine the prevalence and explore predictors of CAM use during early pregnancy in a UK population.

Materials and methods

The subjects were women attending for their mid-trimester (18–21 weeks) scan at the Royal Aberdeen Maternity Hospital, North-East Scotland. With an expected response rate of 40%, 500 questionnaires were distributed over a two month period during 2012 to achieve a minimum of 217 responses, calculated to be the appropriate sample size with a margin of error of 5% and a confidence interval of 95%.

A pilot questionnaire was developed from the published literature reporting the use of CAM by pregnant women[10], [11], [12], [13], [14], [15], [16], [17], [18], [19], [20], [21], [22], [23], [24], [25], [26], [27], [28], [29], [30], [31], [32], and [33]. CAM in our study was defined as the diagnosis, treatment and prevention of illness by various practitioners using therapies such as herbal and homeopathic products, acupuncture, aromatherapy, chiropracty, vitamins and minerals and certain food products. Furthermore as a prompt the questionnaire contained an extensive list of specific CAM modalities and products. The questionnaire content and structure was reviewed for face and content validity by four individuals with experience in the care of pregnant women and associated research, followed by piloting in a random sample of 20 pregnant women, who were excluded from the full study. Minor modifications were made to the questionnaire post piloting.

The final questionnaire contained four sections comprising: health and medication use during pregnancy (4 items); personal use of CAM therapies (7 items, extensive checklist of CAM modalities and products); attitudes toward CAM use during pregnancy (6 items); and demographics (5 items). Questions were a mix of closed and Likert statements. The questionnaire, together with a study invitation letter, information leaflet and reply paid envelope, was distributed at the screening clinics. As the questionnaire was anonymous no reminders were issued.

Data were coded and entered into an SPSS database (SPSS Inc., Cary, NC version 21.0) and analysed using descriptive statistics to profile respondents. Chi-square was used to test association between variables (e.g. age, level of education, ethnic origin etc.) and CAM use in pregnancy. Variables identified as significant in univariate analysis were entered into binary logistic regression.pValues <0.05 were considered statistically significant.

This research was approved by NHS North of Scotland Research Ethics Committee and NHS Grampian Research and Development Committee on 27th June 2011(REC 11/AL/0094).

Results

Of the 500 questionnaires distributed, 332 were returned, giving an overall response rate of 66%. Respondent demographics are reported in Table 1 . The majority were Caucasian, aged over 25 years, and reported a university education.

Table 1 Respondent demographics (n = 332),*missing values, percentages rounded up or down to two significant figures.

  % (n)
Age (years)  
 15–24 13 (43)
 25–34 66 (220)
 ≥35 21 (69)
Living circumstances  
 With spouse, partner 83 (277)
 Other 17 (55)
Education  
 University 52 (172)
 College 29 (97)
 Secondary school 19 (63)
Ethnic origin*  
 White British 80 (260)
 Other 20 (64)
First pregnancy 46 (151)
Existing medical conditions 27 (91)
 Asthma 12 (39)
 Diabetes 3.9 (13)
 Hypertension 3.6 (12)
 Depression 3.0 (10)
 Epilepsy 0.3 (1)
 Others 11 (36)
Concurrent prescribed medication 45 (150)

Two thirds of respondents (63%) reported using CAM (excluding vitamins and minerals) during the early stage of pregnancy. Vitamins and minerals were also used by 73% of respondents. Almost one quarter of respondents (23%) reported using CAM prior to becoming pregnant, of whom one third (37%) stopped on becoming pregnant. Respondents reported using a total of 28 different CAM modalities of which herbal products were the most commonly used by over a third of respondents.

The CAM modalities used, the proportion using, recommender (e.g. health professional, family, friend) and the medical indications for use are reported in Table 2 . The specific herbal products, recommenders and medical indications for use are reported in Table 3 . Twenty-five different herbal products were reported, of which the six most frequently used were: ginger (beyond cooking), cranberry, chamomile, raspberry tea/capsules, tea tree oil and senna.

Table 2 CAM modalities used, who recommended and indications (n = 208).

CAM % Using Recommended by (%) * Reasons for using CAM given by respondents
Doctor Midwife Pharmacist Family, friend Internet Magazine Other
Herbal products 59 (122) See Table 3
Massage 33 (69) 4 39 0 19 7 0 9 Back pain, relaxation
Nutraceuticals 19 (39) 5 21 0 0 8 28 18 General health, constipation, stomach
Aromatherapy 17 (36) 0 17 0 0 0 0 3 Pain, nausea
Yoga 16 (33) 0 12 0 30 6 3.0 36 Back pain, relaxation, general health
Meditation 5.8 (12) 0 17 0 0 8 0 42 Relaxation
Acupressure 2.9 (6) 17 0 0 33 17 0 0 Nausea
Reiki 2.9 (6) 0 0 0 33 0 0 17 Pain
Reflexology 2.9 (6) 0 33 0 0 0 17 50 Pain
Hypnosis 2.4 (5) 0 0 0 40 0 0 80 Relaxation
Homeopathy 2.4 (5) 0 40 0 20 0 0 0 Nausea
Alexander technique 1.9 (4) 0 0 0 25 25.0 0 25 Pain, exercise
Acupuncture 1.4 (3) 0 0 0 0 0 33 0 Pain
Osteopathy 1.4 (3) 0 0 0 33 0 0 0 Pain
Cranial osteopathy 1.0(2) 0 0 0 0 0 0 100 Pain
Chiropractic 1.0 (2) 0 0 0 50 0 0 0 Pain
Chinese medicine 0.5 (1) 0 0 0 0 0 0 0 Fertility

* Do not total 100% due to missing data, percentages rounded up or down to two significant figures.

Table 3 Herbal products used, who recommended and indications (n = 122).

Herbal product % Using Recommended by (%) * Reasons given by respondents for using herbal products
Doctor Midwife Pharmacist Family, friend Internet Magazine Other
Ginger (beyond cooking) 42 (51) 0 26 4 31 12 2 8 Nausea
Cranberry 26 (32) 3 53 0 9 3 0 6 Urinary symptoms, prevention
Chamomile 21 (26) 8 0 8 22 3 14 9 Relaxation, help sleep, digestion
Raspberry tea/capsules 13 (16) 19 6 6 0 13 13 19 Labor preparation, alternative to black tea
Tea tree oil 11 (13) 8 0 8 23 8 0 14 Skin, antiseptic
Senna 9.0 (11) 36 0 36 0 0 0 18 Constipation
Echinacea 7.4 (9) 0 0 0 44 22 11 0 Cold symptoms
Aloe 5.7 (7) 29 29 0 29 0 0 14 Skin
Grapefruit 5.7 (7) 0 0 0 0 0 0 57 Vitamin C
Garlic (beyond cooking) 4.9 (6) 0 0 0 17 0 0 0 Nausea
Eucalyptus 4.1 (5) 0 0 20 40 0 0 40 Cold symptoms
Clove oil 3.3 (4) 0 0 50 0 0 0 50 Dental pain
Evening primrose oil 2.5 (3) 33 0 0 0 0 0 67 Skin
Nettle root 1.6 (2) 0 0 0 50 0 50 0 Nausea
Ginseng 1.6 (2) 0 0 0 0 0 0 0 Nausea
Co-enzyme Q10 1.6 (2) 0 0 0 0 0 0 0  
Bee pollen 0.8 (1) 0 0 0 0 0 0 100 Chapped lips
Others 8.2 (10)                

* Do not total 100% due to missing data, percentages rounded up or down to two significant figures.

The recommendations to use CAM modalities and products during the early stage of pregnancy were principally made by family and friends and midwives. Midwives were more frequently cited by respondents as recommending approaches such as massage, reflexology and homeopathy, while family and friends were more frequently cited for herbals, yoga, reiki and hypnosis.

CAM users were significantly more likely to have used CAM prior to becoming pregnant (p < 0.0001), have family and friends who use CAM (p < 0.0001), to have a university education (p < 0.001), and to be non-white British (p < 0.001). However in binary logistic regression the variables retained were: CAM use by family, friends (OR 4.1, 95% CI 2.3–7.3,p < 0.001); ethnicity, non-white British (OR 3.5, 95% CI 1.8–6.8,p < 0.001) and CAM use prior to pregnancy (OR 2.4, 95% CI 1.2–4.8,p = 0.014). Comparison of CAM users with non-users is reported in Table 4 .

Table 4 Comparison of CAM Users and Non-users (n = 331, 1 missing value), percentages rounded up or down to two significant figures..

Characteristic Users (n = 208) % (n) Non-users (n = 124) % (n) p-Value
Age (years)      
 15–-24 10 (21) 17.7 (22) 0.124
 25–34 68 (141) 63.7 (79)  
 ≥35 22 (46) 18.5 (23)  
Education      
 University 60 (125) 37.9 (47) <0.001
 College 25 (51) 37.1 (46)  
 Secondary school 15 (32) 25.0 (31)  
Ethnic origin*      
 White British 72 (150) 88.7 (110) <0.001
 Other 27 (58) 11.3 (14)  
First pregnancy 50 (103) 39.0 (48) 0.064
Medical condition 28 (58) 26.6 (33) 0.063
Prescribed medication 49 (101) 39.8 (49) 0.124
CAM use before pregnancy 30 (63) 10.6 (13) <0.0001
CAM use by family, friends 51 (105) 16.3 (20) <0.0001

While two thirds of respondents were uncertain whether CAM use was safer than conventional prescribed medicines during pregnancy, users were significantly more likely than non-users, to agree that CAM were safer (p = 0.04). A similar proportion of respondents were uncertain whether CAM were more effective than prescribed medicines (p = 0.551). Just over half of respondents were uncertain whether CAM could interfere with conventional medicines; users were significantly more likely to disagree with this statement (p < 0.0001). Over half of respondents were uncertain if CAM therapies could cause side effects, with users significantly more likely to agree (p < 0.00001). When asked if patients should report CAM use to their health professional three quarters of respondents agreed with this statement, with CAM users being significantly more likely to agree (p < 0.001). Finally when asked whether CAM should be available through the NHS at no cost, just over half of respondents agreed, with users being significantly more likely to agree (p < 0.003). Comparison of the attitudes expressed by CAM users with non-users is reported in Table 5 .

Table 5 Responses of users (U) and non-users (NU) to attitudinal statements regarding CAM use (n = 331, 1 missing), percentages rounded up or down to two significant figures.

Statement % (n) strongly agree/agree % (n) uncertain % (n) strongly disagree/disagree p-Value
U NU U NU U NU
During pregnancy complementary and alternative medicine are safer than conventional medicines prescribed by my doctor 19 (39) 8.8 (11) 63 (130) 73 (91) 19 (39) 18 (22) 0.040
Complementary and alternative medicine are more effective than conventional medicine prescribed by my doctors during pregnancy 6.8 (14) 4.0 (5) 66 (138) 70 (87) 27 (56) 26 (32) 0.551
Complementary and alternative medicine can interfere with conventional medicines prescribed by my doctors 36 (74) 27 (34) 50 (103) 70 (87) 15 (31) 2.4 (3) <0.0001
Complementary and alternative medicine can cause side effects 41 (86) 27 (34) 46 (96) 71 (88) 13 (26) 1.6 (2) <0.00001
Health care professionals should be informed by patients about the use of any complementary and alternative medicine during pregnancy 78 (161) 60 (74) 20 (41) 38.7 (48) 2.9 (6) 1.6 (2) <0.001
Complementary and alternative medicine should be available through the NHS 61 (127) 44 (54) 31 (65) 50 (62) 7.7 (16) 6.4 (8) 0.003

Discussion

To our knowledge this is the first UK study to report the prevalence of CAM use, and the predictors of use during the early stages of pregnancy. Two thirds of respondents reported using CAM, which included 28 different modalities during the early stages of pregnancy. Herbal products were the most frequently cited, with one or more of 25 different products being used by over a third of all respondents. The significant predictors for CAM use identified in our population were: use by family and friends, use before pregnancy, and being non-white British.

Unlike previous reports, our study included a definition of CAM together with comprehensively detailed checklists for both CAM modalities and specific CAM products. A further strength of our study is the relatively prospective nature of data collection minimising recall bias. Limitations however are the use of convenience sampling, with data being collected from only one centre in North East Scotland, and the lack of data from non-respondents, both of which may limit external validity. However the age and ethnicity of our study population are similar to those recently reported demographic statistics of pregnant women in England and Wales [35] .

Although a number of studies have previously reported on the prevalence of CAM use with stage of pregnancy[11], [12], [16], [18], [19], [22], [23], and [27], the general lack of standardised CAM definition, together with the absence of detailed checklists for research participants, makes direct comparison of study results potentially misleading. The only comparable study performed in a UK population, with data more than 20 years old, reported that 6.0% of women used CAM during their first trimester, increasing to 12.4% during the second and 26.5% during the third [11] . The level of CAM use observed in our study is similar to that reported for 67.5% of Qatari women during their first trimester [24] . However this comparison should be interpreted with caution due to the potential impact of culture and ethnicity.

Herbal products were the most frequently reported CAM modality in our study being used by almost half of respondents. This level of use is greater than previously reported from the USA, Australia, Europe and Asia[10], [12], [13], [14], [15], [16], [17], [18], [19], [20], [21], [22], [23], [25], [26], [27], [28], [29], [31], [32], and [33], although similar to the 52.4% reported in a Malaysian population and 59.9% reported by Sim et al. for breast feeding mothers in Australia [36] . However, as stated earlier direct comparison may again lack validity [30] .

Given the global drive toward evidence based medicine [37] and the lack of robust safety and efficacy data for CAM approaches, the use during early pregnancy may be a key issue. Furthermore, in our study over a third of all respondents reported the use of oral herbal products, which in light of the increasing recognition of potential adverse events[38], [39], [40], [41], and [42]and potential for drug-herb interactions [43] , may be significant both for maternal and foetal health.

Logistic regression identified the significant predictors of CAM use during pregnancy as: CAM use by family and friends; ethnicity (non-white British); and CAM use prior to pregnancy. While previous studies have identified predictors for CAM use, including CAM use prior to pregnancy[13], [21], and [28], higher educational attainment[18], [19], and [21]chronic disease/medication[21], [25], and [29], ethnic background/nationality[14] and [21], higher income [14] and age [28] , ours is the first study to highlight the prominence of CAM use by family and friends as an independent predictor for CAM use in the early stages of pregnancy. The importance of family and friends, who may bring a very personal perspective to the decision to use CAM during pregnancy, rather than trained healthcare professionals, may be of concern. However, a recent survey of UK health professionals involved in the care of pregnant women identified that those who were CAM users themselves were eight times more likely to recommend or advise the use of CAM to pregnant women [44] .

Despite the high levels of CAM use, most users were uncertain of the safety, effectiveness or the potential for drug interactions with prescribed medicines. Such a paradoxical situation has been previously reported for women using CAM while breast feeding [36] , in which almost half of respondents believed that herbal medicines were safer than conventional medicines. The explanation for the apparent inconsistency between their stated uncertainty regarding CAM safety and effectiveness, and their decision to use CAM may be complex and involve issues such as control [45] , empowerment and a belief that CAM, especially herbal medicines, are not chemicals [46] . Whatever the reasons for these apparently paradoxical belief sets these issues merit further work to explore relationships between specific CAM modalities and possible concerns expressed by users and the drivers for and expectations of CAM use.

Comments

CAM modalities and CAM products are widely used during the early stages of pregnancy in this study population. The role of family and friends, rather than health professionals, in the decision to use CAM may be of concern and requires further investigation.

Conflict of interest

The author(s) report no conflict of interest.

Funding

This study was funded from internal institutional resources.

Condensation

CAM therapies especially herbals are extensively used by women during the early stages of pregnancy with a key predictor being use by family and friends.

Acknowledgements

We acknowledge the support of all the staff at the antenatal clinic, Royal Aberdeen Maternity Hospital, in carrying out this project and also all the women who participated by completing and returning the questionnaire.

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Footnotes

a Institute of Medical Sciences, The University of Aberdeen, Aberdeen AB24 3FX, UK

b School of Pharmacy and Life Sciences, Robert Gordon University, Aberdeen AB10 7QJ, UK

c Royal Aberdeen Maternity Hospital, NHS Grampian, Aberdeen AB25 2ZL, UK

d Ninewells Hospital and Medical School, Dundee, UK

e Biostatistics, Medical Research Center, Hamad Medical Corporation, Doha, Qatar

f Institute of Medical Sciences, The University of Aberdeen, Aberdeen AB24 3FX, UK

lowast Corresponding author. Tel.: +44 0 1224 438452.