The Influence of Complementary and Alternative Medicine Use in Pregnancy on Labor Pain Management Choices: Results from a Nationally Representative Sample of 1,835 Women

Introduction

The management of labor pain often involves the use of pharmacologic pain management techniques (PPMT), ^{1 –4} and recent years have seen an increase in PPMT use by parturient women during labor, ^1,5 including nitrous oxide, epidural analgesia, or systemic opioids. ^2,3,5 Despite concerns over adverse effects of PPMT, ⁶ the benefits and risks of most PPMT are well understood ⁷ and may inform decisions to use them for labor pain management. The use of PPMT may also be influenced by many other factors, including level of education, level of employment, and area of residence, ^8,9 as well as more specific personal and clinical influences, such as antenatal and intrapartum care provider, parity, and expectations of birthing women and their care providers regarding the level of acceptable pain during labor. ^9,10

Many women ¹ do not want to use PPMT for labor pain, and for these women a number of nonpharmacologic pain management techniques (NPMT) are available. NPMT can be defined as pain management approaches that do not draw on pharmaceutical medications, including breathing techniques, massage, hypnotherapy, transcutaneous electrical nerve stimulation (TENS), hydrotherapy (use of bath, pool, or shower), and acupressure or acupuncture. The spectrum of NPMT available to, and accessed by, birthing women includes treatments that are often categorized as complementary and alternative medicine (CAM), such as massage and acupuncture. ¹¹ Research has examined the effectiveness of NPMT, with varying results. Approaches such as massage, ¹² hypnosis, ^13,14 TENS, ¹⁵ and water immersion ¹⁶ have been found to reduce labor pain. Hypnosis, ¹⁴ water immersion, ¹⁷ and acupuncture and acupressure have been linked to a lower incidence of PPMT use. The current evidence suggests that women receiving antenatal and intrapartum care from a midwife are more likely to use CAM for labor pain management than those consulting an obstetrician. ¹⁰ However, such research has not examined the effect of prior CAM use on women's decisions to use the various available labor pain management techniques. ^18,19

There is substantial use of CAM among pregnant women, ^11,20,21 and safety concerns have been raised regarding the use of CAM in this population, ^{22 –24} including the potential for interactions with PPMT. ^25,26 Such concerns are exacerbated by free access to CAM products without the involvement of trained health care practitioners. ^27,28 There have been preliminary attempts to investigate the effects of specific CAM on the use of PPMT at birth. ^{29 –31} Nevertheless, beyond this work, the bulk of clinical research examining CAM in pregnancy has focused on the immediate effects of CAM treatments for pregnancy-related health conditions. ^32,33 Researchers have also reported the effect of chiropractic care on the risk for cesarean delivery. ³⁴ Like many CAM treatments for pregnancy and birth, the evidence base provided by these studies is weak because of small sample sizes and other methodologic issues. ³⁵ Furthermore, research exploring the effectiveness of specific CAM treatments has been undertaken with little attention to other aspects of CAM (such as the practice behavior of CAM therapists) ³⁶ or the diversity of practice approaches and philosophies espoused by different CAM practitioner groups. ^{37 –41} In particular, the influence of the exchanges between CAM practitioners and pregnant women on women's engagement with conventional maternity care, including the use of pain management techniques, remains unexamined. Similarly, the CAM products and treatments used by women who are concurrently choosing PPMT for labor pain is currently unknown.

In response, this paper reports findings from the study of a large, nationally representative sample of pregnant women, providing the first detailed examination of the use of a range of CAM during pregnancy and the association between the use of both NPMT and PPMT for labor and birth.

Methods

The study sample was drawn from the Australian Longitudinal Study on Women's Health (ALSWH). ALSWH is a longitudinal population-based survey examining the health of over 40,000 Australian women. The sample is stratified according to age, with older (born 1921–1926), mid-age (1946–1951), and young (1973–1978) cohorts who were randomly selected from the national Medicare database to explore a variety of factors affecting health and well-being of women over a 20-year period. The present study is based on the “young” cohort (n=8012), who were aged 31–36 years in 2009. The study sampled women who stated in the 2009 ALSWH survey (survey 5) that they were pregnant or had recently given birth. This group of the young cohort (n=2445) was invited to participate in an additional subsurvey administered in 2010. The substudy reported here was approved by the relevant ethics committees at the University of Newcastle (#H-2010_0031), University of Queensland (#2010000411), and University of Technology Sydney (#2011-174N).

Results

There were 1835 women (response rate, 79.2%) who responded to the substudy survey and were included in the analysis. The respondents were most commonly married (96.3%), with one (38.0%) or two (38.2%) children, and living in an urban area (62.4%) (Table 1). As seen in Table 2, some women reported having a diagnosed health condition in the previous 3 years (mean±standard deviation, 0.9±1.10) and reported experiencing an average of 4.5±3.12 health symptoms in the previous 12 months.

For their most recent pregnancy, the women accessed care from all three conventional care practitioner groups (general practitioners, midwives, and obstetricians), with general practitioners (90.1%) most commonly accessed (Table 1). Among the respondents there was a high prevalence of back pain (39.5%), reflux/heartburn (34.7%), and nausea (32.9%) associated with their most recent pregnancy (Table 2).

A substantial number of participants used PPMT during labor and birth (81.9%), and slightly fewer women used NPMT (74.4%). Many of the women (62.6%) used both NPMT and PPMT for intrapartum pain management. The majority of participants (60.7%) used some form of CAM, either consulting with CAM practitioners (48.4%) or using CAM products/treatments (39.4%) for pregnancy-related health concerns. A large number of women consulting with a CAM practitioner (80.7%) or using a CAM product/treatment (77.7%) also used PPMT during their birth.

More than two thirds of women (66.7%) who used NPMT for their labor and birth also used some type of CAM during their pregnancy. About half of the women who used NPMT accessed CAM practitioners (53.0%) or used CAM products/treatments (49.0%) for pregnancy-related health conditions. The bivariate chi-square analysis of the variables of interest is presented in Tables 3 and 4.

The multiple logistic regression models are presented in Tables 5 and 6 for each labor pain management technique. This analysis indicates significant associations between the use of CAM products/treatments and consultations with CAM practitioners for pregnancy-related conditions and the use of NPMT more than PPMT. Women who consulted with an acupuncturist (odds ratio, 2.79; p=0.01) or attended yoga or meditation classes (odds ratio, 2.92; p=0.001) were more likely to use breathing techniques during their labor to manage pain. Likewise, women who used herbal medicine (odds ratio, 2.26; p=0.02), aromatherapy oils (odds ratio, 4.81; p≤0.001), herbal teas (odds ratio, 1.87; p=0.003) or practiced yoga or mediation at home (odds ratio, 4.13; p≤0.001) showed a similar trend. Although women who consulted with a naturopath or herbalist (odds ratio, 4.01; p=0.01) were more likely to use acupressure or acupuncture as a pain management technique, women who consulted with an acupuncturist were 15.09 times more likely (p≤0.001) to use this method, highlighting a particularly strong relationship.

In summary, these results show that many women who use CAM during pregnancy also use NPMT to manage pain during labor and birth. The findings of this study also indicate that CAM use during pregnancy does not appear to affect intrapartum use of PPMT. Despite these trends, the associations between use of CAM during pregnancy and pain management during labor and birth is not consistent across all CAM and differences are apparent across the CAM practices, products, and treatments examined.

Discussion

Drawing on a nationally representative sample of pregnant women, this paper reports the first examination of the relationship between the use of a range of CAM, including products, treatments, and consultations with CAM practitioners and women's use of pain management through labor. Our analysis identifies three key findings. First, this study reports a substantial proportion of women who use PPMT during labor and birth and also access a range of CAM for pregnancy-related health conditions. Previous research has identified that 49.4% of pregnant women consult with a CAM practitioner for pregnancy-related health conditions. ²¹ The relationship between CAM use in pregnancy and the use of PPMT for labor pain has not previously been examined. Our findings indicate that this aspect of maternity care requires closer attention from both clinicians and researchers to allow women who use CAM during pregnancy to be fully informed and those providing care to women during pregnancy and birth to feel confident in their ability to do so safely.

Second, our study identifies a relationship between women's use of a range of CAM during pregnancy and a higher use of NPMT for labor compared with women who do not use CAM. While the overall characteristics of women who use NPMT have not been examined, there is some indication that women laboring in birth centers have access to a diverse range of NPMT. ⁴² However, the majority of participants did not give birth in a birth center or community but in a hospital. There is limited examination of whether CAM is offered by maternity care staff in a hospital setting. Preliminary evidence does suggest that hospital midwives are supportive of women's use of CAM and may be incorporating CAM within their own practice where possible. ^{43 –46} There is also a reported disparity between the perceptions of professional groups in maternity care toward NPMT, such as a stronger alignment with natural methods of maternity care with midwives than with obstetricians. ⁴⁷ Although previous research has found that women's attitudes influence their decisions to use epidural analgesia for labor pain management, ¹⁰ no studies have examined women's perceptions of NPMT for managing labor pain. Nonpharmacologic treatments, however, may be considered by pregnant women to be equally efficacious as pharmacologic treatments for managing pregnancy-related health conditions, while also being natural and safe. ¹¹ It has also been reported that women prefer to minimize their drug use during labor and that this preference affects their use of PPMT. ⁴⁸ More recent research has concluded that women may hope for a labor free of pain relief, but they often find that they need or benefit from PPMT all the same. ⁴⁹ Given the accumulation of our findings in conjunction with previous studies, it is important that future research examine the attitudes toward health, pregnancy, and birth held by pregnant women in relation to their use of NPMT.

A third trend identified in this study suggests that women who use CAM use more NPMT than women who do not use CAM. This may occur because women who use CAM in pregnancy attempt to minimize their use of PPMT during birth by using NPMT to a much greater degree than non-CAM users. Although preliminary clinical research has reported reduced experience of pain for women using NPMT, including massage, ⁵⁰ hypnotherapy, ¹⁴ TENS, ¹⁵ acupuncture, ⁵¹ acupressure, ^52,53 and water immersion, ^16,54 only hypnotherapy, acupuncture, and water immersion have been linked to reduced use of PPMT. ^14,51,54 The lower rates of use of any PPMT by women who practiced yoga or meditation at home are supported in part by past preliminary research identifying higher levels of comfort during labor for women who practice yoga throughout gestation; however, this finding does not transfer to a reduction in PPMT (specifically pethidine) in labor. ²⁹ In contrast, there is no clear evidence to explain the use of aromatherapy or osteopathy during pregnancy to reduce the overall use of PPMT at birth. There is some evidence that using aromatherapy oils, such as clary sage (Salvia sclarea) or chamomile (Matricaria recutica or Chamaemelum nobile), during birth may alleviate pain, ^30,31 but this has still not been linked to any reduction in the need for PPMT during labor. Likewise, there is some evidence that osteopathy may reduce the experience of back pain during pregnancy, ³² but whether this results in reduced pain and consequent use of PPMT at birth remains unexamined.

Women in this study who practiced yoga/meditation at home or consumed herbal tea for pregnancy-related health conditions were more likely to use all NPMT during their labor. Several reasons for this relationship can be considered. This pattern may reflect an “alternative” lifestyle choice being more fully embraced by women using these particular CAM practices/treatments. Particularly given that yoga philosophy encourages a number of lifestyle behaviors beyond the practice of yoga positions, including dietary choices, breathing practice, and emotional balance, ⁴¹ the home practice of this type of CAM may indicate a more profound engagement with the philosophy of yoga compared with those who only practice yoga while attending classes. Similarly, the consumption of herbal tea may reflect a change in dietary habits, which has been found to occur in a stepwise manner where broader changes (such as reduced fat intake) occur first and more specific changes (such as increased fruit and vegetable intake) are initiated much later. ⁵⁵ It is possible that herbal tea consumption may follow increased fruit and vegetable intake as a later and more specific change. This is supported by other research, which has found that women who consume decaffeinated coffee are more likely to take supplements, eat cruciferous vegetables, and exercise regularly. ⁵⁶ Despite these possible explanations for this finding, this topic is largely unexplored. Empirical data are clearly needed to understand it better.

The women who consulted a naturopath or acupuncturist or attended meditation/yoga classes for pregnancy-related health conditions were more likely to use a number of NPMT at birth than CAM nonusers. This connection may be related to CAM practitioners providing information and recommendations to pregnant women to assist with their birth choices. Although commentators have called for research exploring CAM practitioners' approaches to pregnancy and birth, ³⁶ no current research has examined this topic. Current research does highlight the value placed on the time CAM practitioners take for consultations as important for CAM users. ⁵⁷ This time may be used by a practitioner such as a naturopath to provide information to patients that aligns with core philosophical values. ³⁷ Alternatively, women consulting with CAM practitioners are more likely to hold a holistic orientation to health, ⁵⁸ and CAM users may be self-selecting NPMT according to their own personal philosophy of birth, rather than being encouraged to incorporate such methods into their birth choices by a CAM practitioner. An interesting contrast to this, however, is the absence of such a strong relationship between NPMT use and consultations with an osteopath, chiropractor, or massage therapist. The pattern of lower use of NPMT for women consulting with a chiropractor, osteopath, or massage therapist may reflect less interaction with patients because of the manual nature of the therapies. ^39,40 These therapies may otherwise be accessed by women who do not have the holistic orientation of health described previously. However, while some attempts to examine the difference in user profiles between those engaging with discrete CAM modalities have been undertaken, ⁵⁹ research in this area has not yet compared the attitudes and perceptions of these groups toward their health and toward CAM in general.

The findings of this study are reinforced by its strengths: a large and nationally representative sample of pregnant women and a high response rate. This study also provides new insights into the effect of CAM use during pregnancy and the use of pain management techniques during labor and birth. Interpretation of our findings may be limited by the lack of confirmation of pain management techniques reported by the women. The women's use of CAM and consultation with CAM practitioners is self-reported, and as such findings could be affected by recall bias. Also, although the ALSWH cohort is nationally representative, characteristics of some subpopulations may differ (e.g., use of health services, birth settings, and socioeconomic status) and as such these findings may not clearly transfer into very specific subsets of birthing women. Regardless of this the ALSWH is a respected source of epidemiologic data examining women's health in Australia, and these limitations are outweighed by the opportunity provided from conducting the first analysis of CAM product/treatments and practitioner use during pregnancy, and their relationship with pharmacologic and nonpharmacologic pain management techniques, in a large, nationally representative sample of pregnant women.

Conclusions

These findings indicate a need to more closely inspect the factors influencing women's use of pharmacologic and nonpharmacologic pain management techniques during labor and birth. This analysis also highlights the need to examine CAM as discrete and separate practices and treatments rather than as a homogenous category to better understand its effects on pregnancy and birth. Given the diversity in outcomes linked to different CAM practices, such research will provide more meaningful insights into the motivations, influences, and effects of each CAM therapy. In line with this, there is also a need to explore the practice behaviors of a variety of CAM practitioner groups in the care for pregnant women, with a particular focus on the information provided and health behaviors encouraged during their consultations. The attitudes and motivations that influence pregnant women's decision-making about pregnancy and birth also require closer examination. This knowledge is important for all health professionals, organizations, and policymakers involved in maternity care.