Effects of music intervention during caesarean delivery on anxiety and stress of the mother a controlled, randomised study

Almost one in three women delivers by caesarean in Germany. Thus it is the most common abdominal surgery and one of the most common operations. Although the circumstances in almost all cases give cause for joy, it is also a feared event, which is associated with a significant level of stress for the patient [1, 2]. Studies have shown adverse effects of maternal stress on the foetus and on psychological development later in life [3, 4]. In addition, it is known that increased levels of stress and anxiety can negatively affect pain perception and the usage of analgesics postoperatively [5, 6] as well as the new mothers lactation [7, 8]. In view of the limited pharmacological options of intervention for pregnant women, the need for alternative, low-risk approaches to positively influence anxiety and stress arises.

In this regard, the positive effect of music on anxiety and stress is one of the oldest treatment approaches. Even Asclepius attributed a healing power to music [9]. Its positive influence in various medical interventions across all disciplines has been repeatedly examined [10‐13]. Supported by a recent review by Hole et al. in the Lancet, these results also drew the attention of the wider public [14].

Nevertheless, data for music during caesarean are sparse and inconclusive [15]. Two randomized studies examining the influence of music during the pre-operative waiting time could show a positive influence of music on non-validated questionnaires as well as heart rate and heart rate variability as a surrogate for stress and anxiety. In part, this effect could still be detected six hours after the caesarean [16, 17]. A Cochrane analysis [15] investigating the effect of music during the procedure could only identify one randomized study that was able to show a positive effect of music intervention on heart rate at the end of the caesarean in 64 participants [18]. Due to their study design, no further conclusions on subjective and objective perception of anxiety were possible. Another study examined the influence of music during caesarean delivery under general anesthesia on postoperative pain and could not show any effect [19].

Therefore, the aim of the present study is to systematically examine the anxiolytic and stress reducing effect of a music intervention during the caesarean on the wake patient using validated questionnaires and a comprehensive set of objective measurements (salivary cortisol/amylase, blood pressure and heart rate).

The SAMBA (Sectio Caesarea und die Auswirkung von MusikBegleittherapie auf Anxiolyse; English: Caesarean and the effect of music intervention on anxiety) study is a single-centre, controlled, randomized trial conducted at the University Hospital Dusseldorf, Germany. The study adheres to the CONSORT guidelines.

We screened and informed 412 patients about study participation. Sixty-two patients had to be excluded from further participation because they no longer fulfilled the inclusion criteria at the time of intervention (three had delivered spontaneously, 18 had an indication for caesarean preterm, 41 had a secondary caesarean (for example because of premature rupture of membranes)). Forty-five women did not take part due to technical difficulties (reconstruction of the operation theatre). One patient discontinued the study prematurely. In total 304 participants completed the study in accordance with the protocol (Fig. 2). The patients had a mean age of 33.6 years (range: 18–47 years) and a mean gestation age of 268.5 days. The data revealed that the two groups did not differ regarding the time of the procedure (morning vs. afternoon) [χ²(1, 301) = 0.75, p = .388] nor on the duration of the procedure [t(290) = 1.36, p = .175].

An overview of the descriptive data of the music and control group and the main results is given in Table 1.

Overall, the study shows, in subjective as well as objective dimensions, an anxiety and stress reducing effect of music during caesarean.

While both groups showed high baseline values for STAI-state and VAS-A without significantly differing from each other at admission, the subjective anxiety drop in both, STAI-state and VAS-A, was significantly higher in the music group and resulted in significantly lower anxiety scores compared to the control group at skin suture. The shown positive effect of music on these subjective measures for anxiety and stress is in line with previous studies investigating the effect of music in the context of caesarean and other medical procedures [11, 13, 14, 16, 23, 26]. One of these studies showed a persisting positive effect for six hours [16]. Our data support this observation insofar that women in the music group had significantly lower scores on the VAS-A for another two hours after skin suture. This effect was not found for the STAI-state. It is likely that the STAI-state is less appropriate than the VAS-A in the obstetrical environment due to the duration of the survey?

In terms of objective parameters, the music group showed a significantly lower increase in salivary cortisol than the control group from admission to skin suture. Saliva cortisol measures the impact of a stressor with a latency of about 30 min [27]. In this respect, the measurement at skin suture represents a large part of the objective stress sensation during the operation [2]. Therefore, the present result reflects that the music group also objectively experiences reduced stress levels during the caesarean. A lowering effect of music on cortisol could also be shown in studies in other medical fields [28].

A comparable effect could not be found for salivary amylase. Whereas cortisol represents the activity of the hypothalamic-pituitary-adrenocortical axis, salivary amylase represents the activation of the sympathetic nerve system [29]. In line with previous work on stress during surgical procedures, our study shows no measurable difference in salivary amylase between the groups [30, 31]. This might be an indication that there are unrecognized factors, which impede a reliable interpretation of the salivary amylase during surgical procedures.

A variety of studies have examined the influence of music on the cardiovascular system [32]. In addition to a direct impact on the dopaminergic mesolimbic reward centre [33], an interaction of the external musical rhythm with the internal body rhythms of heart and respiratory rate as a main carrier of the effect of music is debated [34‐36]. Thereby, the value of systolic blood pressure and heart rate is well documented as objective parameters reflecting stress and anxiety [32]. In the present study, the music group showed significantly lower heart rate and systolic blood pressure levels at skin incision. This took place on average 18 min after the patient had been admitted to the operating room and the start of the music intervention. Therefore, we would argue that the calming effect of music on the expectant mother was already present at skin incision. In the case of skin suture, however, no significant difference was detectable. At this time, the new-born was usually already in the arms of the mother, so that pulse and blood pressure are certainly subject to an undetermined bias.

Besides the positive influence of music on the measured stress and anxiety of patients, the high acceptance of the intervention should also be noted. Ninety-six percent of women in the intervention group would want to hear music again during a possible repeated caesarean, regardless of any therapeutic effects. The positive response of the women regarding the music intervention alone are gratifying and should encourage the use of music in obstetrics and further research in this area.

A limitation of the study is the lack of opportunity to gain an even more comprehensive picture of the course of anxiety during caesarean through measuring more time points. For example a measurement of anxiety levels just before the women enters the operating theatre would be desirable as this time point may be the most anxious time for the women. This is partially compensated by the fact that the different measuring instruments used in this study have different latencies and thus cover a large period of time around the intervention. Additionally, in order to ensure a trial close to normal conditions of a caesarean and the needs of the woman, we decided not to use headphones, in contrast to other studies [18]. Naturally, this impeded blinding of the study staff. Using group blinded analysis and application of objective parameters such as saliva cortisol, this disadvantage was accounted for as far as possible. Another limitation which could have influenced the study results is the lack of data on the relationship and role of the nurses and other health professionals in usual interaction and information sharing with the woman during and after procedure.

We would like to emphasize that with a large sample of 304 participants and several measurement time points throughout the day of the caesarean as a strength of the study. This is the first study in this area of research that has the necessary power to detect even small effect sizes.

In view of the results, the present study should have implications for clinical practice. Music is a simple, inexpensive, effective and safe intervention that can be easily implemented in everyday clinical practice. Therefore, it would be desirable if the possibility to listen to music could be routinely offered to women giving birth by caesarean. However, further research should consider the impact of music on the surgical team. Although previous work showed adverse effects only for high volumes and complex interventions [37], this has not been investigated explicitly in the context of caesarean.

In conclusion, the results of the present study show that music during caesarean has an anxiety and stress soothing effect on the wake patient. Implementation in clinical routine therefore seems advisable.