Music and Perinatal Stress Reduction

Editor’s Note: Dr. Fred Schwartz is a board certified anesthesiologist, practicing at Piedmont Hospital in Atlanta, Georgia. He is a member of the International Society for Music in Medicine, the National Association for Music Therapy as well as APPPAH. He has used music in the operating room and delivery suite for over 20 years, and for the last 10 years has also produced music for pregnancy, childbirth and babies. Direct all correspondence to 314 Woodward Way NW, Atlanta, Georgia 30305 or email: drmusic@mindspring.com. This article was published by permission of Dr. Schwartz and the Journal of Prenatal and Perinatal Psychology and Health, 12(l), Fall 1997

Abstract: The author uses his experience as an anesthesiologist involved in music medicine to discuss the psychophysiology of perinatal stress. The use of music as an adjunct to medical care for mother and child in the prenatal and postnatal period, as well as the implications for improved outcome and medical cost savings are addressed. The importance of the fetal auditory environment as a conduit for communication and learning is also examined.

From the viewpoint of the anesthesiologist, consciousness is manipulated both chemically and psychotherapeutically to result in decreased pain, altered recall, and a decreased stress response. One of the common elements in my work has been the use of stress reduction techniques during various states of consciousness. I have found that both anesthesia sedation and general anesthesia can open up pathways in the mind to healing therapies. Music and guided imagery can also have powerful healing qualities. When used together during anesthesia, these audio therapies can be used to complement the stress reducing properties of anesthesia and promote faster healing.

Some of the benefits of music in the labor and delivery suite that complement anesthesia are that it speeds up labor and decreases the amount of pain. It also decreases the stress response to labor which is beneficial to both mother and newborn. Couples coming to a delivery suite frequently perceive it as a foreign and unfamiliar environment. The act of choosing a musical program for childbirth allows a couple to exert some control over their environment. Music is very personal in that a particular piece may have a connection with certain past experiences and emotions. This acoustical painting of the hospital environment has been shown to make it less hostile and less anxiety provoking for patients. Since pain and enjoyment emerge as two distinct, though related dimensions of the birth process, music can express both the struggle and the joy of the occasion. The beauty here is that the benefits of the music can be utilized during natural childbirth, with childbirth under epidural anesthesia, and if need be during Cesarean section. Music can help the newborn know that a special event is happening and when the newborn comes into this world the music along with the familiar sound of voices is indeed special.

Music is particularly useful during Cesarean sections. Most anesthetics for C-sections are performed under epidural or spinal anesthesia. The pregnant mother is anesthetized from the chest down. Usually no intravenous sedatives or narcotics are given to the mother until the baby is born, because these can cause sedation or respiratory depression in the newborn. There is often some degree of discomfort for mother before the baby is born, when the uterus is manipulated. Music is an effective way to decrease the discomfort here. I try to get a feel for what the couple and their unborn child find soothing. If they do not have an idea of what they want to hear, I usually suggest classical music or new age music. To me, this type of music fits beautifully with C-sections. To give you an idea of the contrast of requests I have had I will relate to you a Friday evening when there were 3 C-sections in a row. The first 2 were done to Beethoven Piano Sonatas. Our last couple was asked what they and their baby wanted to hear, and the mother replied, “My baby only likes rock and roll, but you have to play it real loud.” She picked Bruce Springstein’s “Born in the USA” and this did seem fitting for the occasion.1

An exaggerated stress response has negative effects during pregnancy and childbirth, just as it is detrimental in most disease processes. Most of the physiologic effects of stress are mediated through stress hormones called catecholamines. In the pregnant patient, elevated levels of these stress hormones cause decreased effectiveness of uterine contractions (Simkin, 1986). Some of these patients end up needing C-sections because of this. Intense anxiety has been associated with fetal death in the third trimester (Myers & Myers, 1979). More commonly, the extremely anxious patient in labor will have high catecholamine levels which decrease placental blood flow and can cause fetal distress. This is further compounded if the laboring patient hyperventilates, which can further decrease placental blood flow.

Music’s ability to slow respiratory rates and decrease the stress response is beneficial during labor. It has been shown to have the ability to shorten labor (Winokur, 1984). Even when the course of labor does not speed up when music is utilized, the perceived length of labor decreases (Clark, McCorkle & Williams, 1981). Other studies have shown that when music is played, pain is decreased (McKinney, 1990, Hanser, Larson & O’Connell, 1983).

During my wife’s first pregnancy, I began to think about the environment of our unborn child. I knew that the fetus could respond to music and sound in the womb and I became fascinated with the implications of the constant exposure of the fetus to placental blood flow sounds. Some earlier studies had been done by psychologist Lee Salk (1973), who noticed that most new mothers exhibited a natural preference for holding their infants on the left side of their chest near the heart. Dr. Salk analyzed a number of popular books containing a large number of photographs and artistic representations of infants and adults. Almost 80% of these showed mothers holding their infants on the left side of their chests. This preference extended across all cultures. Balancing groups for left and right-sided dominance, Dr. Salk then replicated this left-sided preference in a large group of new mothers and babies (and used these heart sounds to calm newborns in the hospital nursery). He reasoned there was an imprinting of placental sounds in utero so that sounds after birth remind the baby of the womb experience. This would explain some of the rhythmic similarities of modern music to intrauterine rhythms.

Others have connected the similarities between womb sounds and the “nonsense sounds” that mothers use in talking to their babies. Some of these calming sounds are hush, hush (English) shah (Yiddish), ushuru (Ethiopian), and Insh’allah (Egyptian). Perhaps the similarities to womb sounds also explain the spiritual use of similar sounds in different religions, i.e. “Om” in Buddhism), “Shalom” in Hebrew, Tibetan overtone chanting, and Gregorian chants.

Ultrasound studies have shown that at 16 weeks gestation the fetus can respond to outside sound (Hepper, 1994, Shahidullah & Hepper, 1992). The sounds of the blood flow through the placenta can be heard at a very loud level in the womb. For the lower sound frequencies below 500 Hz, mean sound levels are 80 decibels with peaks to 95 decibels (Gerhardt & Abrams, 1996). This is about as loud as it gets on a crowded dance floor on a Saturday night. A good deal of attention has been given to the so called Mozart Effect where exposure to this music briefly increased spatial IQ in college students (Rauscher, Shaw & Ky, 1995), as well as work with preschool children showing that music training can enhance language development, spatial, and mathematical abilities (Rauscher, et al, 1997). Evidence points to the fact that similar learning benefits extend far back into the prenatal period, and that the sounds and rhythms in the womb may contain information important to the development of the fetal brain (Devlin, Daniels & Roeder, 1997, Shetler, 1989). The newborn can differentiate a recording of his own mother’s prenatal womb sounds from a recording of another mother (Righetti, 1996). The newborn can also differentiate emotional content in the recording of his prenatal womb sounds and respond with changes in movement and heart rate (Righetti, 1996).

There is a vast amount of potential information available to the fetus that can be given in the playing of just one musical note or in singing or talking a single syllable. The content of this sound is both informational and emotional and can be used by the fetus in profound ways. The synaptic network in the fetal brain as well as the infant brain undergoes learning-dependent reorganization. This process involves synaptic “pruning” or regression of neural circuits, as well as synaptic sprouting in the developing brain. This is consistent with the observation of psychologists that infants and children may have enhanced behavioral abilities that they lose later in life (Johnston, 1995). Since fetal hearing is probably the major component of this learning-dependent synaptic pruning and sprouting, the fetus is participating in a second and third trimester auditory amphitheater that is perhaps more important that any later classroom. We have only begun to explore the connection between sound and neurobiological development in the fetus and newborn.

My interest in the fetal audio environment led to a musical collaboration with Burt and Joe Wolff. We produced a musical recording of womb sounds and female vocal sounds’ called Transitions(tm) and a subsequent series of womb sound recordings for pregnancy, childbirth and children.2 It was clear to us that this type of music was very soothing to the newborn, and especially for the premature baby.

A subsequent study showed that stimulation with the Transitions(tm) womb sound music was helpful in the care of mechanically ventilated, agitated premature babies with low oxygen levels. Significant increases in oxygen saturation as well as decreased levels of agitation were found with the use of music (Collins & Kuck, 1991).

Another study showed that when lullaby music was played in the neonatal intensive care unit (NICU) that there were less episodes of oxygen desaturation (Caine, 1991). No doubt that some of the high-decibel sounds from alarms and equipment in the NICU are harmful to the neonate. In one study a group of premature babies were insulated from their audio environment with earmuffs (Zahr & Traversay, 1995). These infants had higher oxygen saturations and spent more time in sleep compared to control group infants. Other studies have shown a doubling of daily weight gain when premature babies in the NICU were given music therapy (Caine, 1991, Coleman, Pratt & Abel, 1996). Additional studies using music with premature babies have shown a 3- to 5-day earlier discharge from the NICU (Caine, 1991, Coleman, Pratt & Abel, 1996, Standley, 1996).

Increased stress response consumes precious calories. It is now clear that the use of music therapy not only has a beneficial effect on the growth and development of premature babies, but may lead to cost savings in their medical care–a significant problem in modern society. In the United States alone, the extra cost of intensive care for these low birth weight infants is over $1,000. per day or over 3.5 billion dollars a year. Later added costs of special education and continued medical expense for these children are even larger than the initial costs for their NICU care (Lewit, et al, 1995). Many of these babies suffer hearing and visual impairment, mental retardation, cerebral palsy or learning disabilities. Ultimately, the uncountable costs are paid by human beings who are not able to realize their full potential. So it appears that with a relatively small expenditure for music in our neonatal ICU’s we could decrease the time in the NICU by over 3 days and save over $3,000. for every premature baby.

Premature birth is the predominant cause of low birth weight and neonatal mortality in the United States (Wegman, 1996). In the US almost one in one hundred babies dies shortly after birth. (Paneth, 1995). This is the highest mortality rate of all the industrialized countries. Despite our best efforts, the consequences of premature labor will continue to be a huge problem for society. Despite a large investment in research and programs to prevent premature birth, the incidence of prematurity in the US has not decreased (Paneth, 1995).

A number of risk factors have been associated with prematurity and low birth weight (See Table 1). Many of these factors are interrelated. In the United States, a large amount of premature births occur in adolescents, a group with higher rates of poverty, lack of prenatal care, poor nutrition, stress, tobacco use, alcohol intake, and drug abuse (Shiono & Berman, 1995, Hedegaard, Henriksen & Niels, 1996).

To gain more insight into premature birth it is interesting to look at some of what we know about how labor is initiated. Thousands of years ago, Hippocrates believed that the baby decides when the birth process begins-a fact that has been confirmed by research today (Nathanielsz, 1995). Evidence points to fetal initiation of labor about 2 to 3 weeks before birth. In the fetal brain, the hypothalamus increases secretion of CRH (corticotrophin releasing hormone) and this stimulates the pituitary to release ACTH (adrenocorticotrophin). This stimulates the fetal adrenal cortex to secrete cortisol. The placenta reacts by producing more estrogen and less progesterone which eventually triggers the contractions of labor.

Since we know that the fetus is involved in initiating labor, it is interesting to wonder why the fetus would initiate premature birth. We know that pregnancies filled with stress are more inclined to conclude prematurely. Use of tobacco and cocaine also increase the stress response in the mother and this is probably true for the fetus as well. There is a biologic explanation for the fetus being able to react to maternal stress by initiating labor. In the human species, our fight or flight stress response was often effective for our survival. In modern times, the stress response is seen as a catalyst for disease. It stands to reason that for biologic survival of the species there would be a mechanism to allow initiation of labor under stressful conditions. Especially in the past, it was much more common for the pregnant woman and fetus to be exposed to the risk of cataclysmic death from the environment or infectious diseases and epidemics. In these situations, some of these premature babies might survive. For the mother, delivery of the baby would allow her to direct her energies toward survival and future childbearing. Despite a large amount of research dedicated to prevention of preterm labor, the incidence of prematurity in the US has not decreased (Paneth, 1995).

Table I Factors Associated with Low Birth Weight

Age below 18 years Drug and alcohol use Previous preterm delivery Infection Tobacco use Lack of prenatal care Maternal stress Poverty

A number of factors have been associated with the risk of prematurity and low birth weight (Table 1). Many of these factors are interrelated. In the United States, a large amount of these premature births occur in the adolescents, who as a group have higher rates of poverty, lack of prenatal care, poor nutrition, stress, tobacco use, alcohol intake, and drug abuse (Shiono & Berman, 1995, Hedegaard, Henriksen & Niels, 1996).

To gain more insight into premature birth it is interesting to look at some of what we know about how labor is initiated. Thousands of years ago, Hippocrates believed that the baby decides when the birth process begins. There is now good evidence to show that the fetus does initiate labor (Nathanielsz, 1995). Evidence points to fetal initiation of labor about 2 to 3 weeks before birth. In the fetal brain, the hypothalamus increases secretion of CRH (corticotrophin releasing hormone) and this stimulates the pituitary to release ACTH (adrenocorticotrophin). This stimulates the fetal adrenal cortex to secrete cortisol. The placenta then produces more estrogen and less progesterone and this eventually sets off the contractions of labor.

Since we know that the fetus is involved in initiating labor it is interesting to speculate on why the fetus would initiate premature birth. We do know that pregnancies that contain a lot of stress are more inclined to be concluded prematurely. Tobacco and cocaine use increase the stress response in the parturient, and this likely is true also in the fetus. There is a biologic explanation for the fetus being able to react to a maternal stress response by initiating labor. In the human species, our fight or flight stress response was often effective during primitive times for our survival. Although in modern times this response has become more of a catalyst for disease. It stands to reason that for biologic survival of the species there would be a mechanism to allow initiation of labor under stressful conditions. In the past, it was much more common for the pregnant woman and fetus to be exposed to the risk of cataclysmic death from the environment or infectious diseases and epidemics. In these situations, some of these premature babies might survive. For the mother, delivery of the baby would allow her to direct her energies toward survival and future childbearing.

As far as other possible mechanisms for initiation of labor, there could be some hormonal transfer from the mother to the fetus through the placenta. Or perhaps a lack of certain nutrients either from poor maternal diet or decreased supply of these nutrients via decreased placental blood flow. Perhaps there is a kind of dialogue that goes on during pregnancy between the mother and her unborn baby that is interrupted in some way by maternal stress. What about the transfer of emotions (or lack of) from the mother to the fetus? It is obvious that the expression of love, nurturing and acceptance is expressed by the mother to the fetus by her voice; through the wide gamut of tonality, rhythm and inflection produced by her talking and singing. It is very possible that this vocal information (or lack of) has an effect on the fetal initiation of labor. It is intuitive that there is a profound interplay of information and emotion involved in this sacred and precious dialogue.

Another possibility is that fetal hearing of the maternal blood flow sounds may in some way cause the fetus to initiate premature labor. Is there some way in which the fetal brain processes changes in womb sound rhythms? Biologic rhythmicity is a fundamental aspect of healthy human beings. For example, the rhythm of our heart beat is not like a metronome but contains a beat-to-beat variability. As we age the variability of our biologic rhythms decrease. And when we reach death, there is no rhythm or variability. The fetus in distress usually has a decreased variability of the fetal heart rate. These changes are sometimes used diagnostically to make clinical decisions during pregnancy and childbirth. Since the predominant rhythmic component of fetal intrauterine hearing is the sound of the mother’s blood flow pulsing through the placenta, is it not likely that the fetal brain uses this sound and rhythmic information in deciding to initiate labor? We know that maternal stress often manifests in a hyperactive sympathetic nervous system and a decrease in maternal heart rate variability (Ekholm, et al, 1996). So perhaps the fetus perceives decreases in maternal heart rate variability and uses this information as part of the initiation of preterm labor.

Another possible cause for preterm labor is an exaggerated maternal apprehension for the safety of the baby as well as the worry that Braxton Hicks contractions are foreboding a premature labor (Cheek, 1995). This will usually provoke a call to the midwife or obstetrician and bedrest and other treatments to prevent preterm labor. This will often increase the patient’s anxiety even more and lead to continuing painful Braxton Hicks contractions. The quality of telepathic communication from the mother to the fetus will reveal anxiety and be picked up by the fetus. This may provoke initiation of the labor cascade by the fetus. Hypnosis during this time has been successful in prolonging the pregnancy (Cheek, 1995, Omer, Friedlander & Palti, 1986).

What appears to be a common attribute here is that an exaggerated maternal stress response can lead to the initiation of preterm labor. Besides the documented clinical use of hypnosis in the treatment of preterm labor, meditation has been documented to decrease stress hormone levels in various clinical situations (Sudsuang, Chentanez & Veluvan, 1991). Music alone has been shown to diminish stress-induced increases in stress hormones (Spintge & Droh, 1987). Music combined with guided imagery also decreases stress hormone levels (McKinney, Tims, Kumar & Kumar, 1997; McKinney, et al, 1997 and Bonny, ND). Music therapy has also decreased maternal stress for pregnant adolescents (Liebman & MacLaren, 1991).

My interests led me to develop a tape of guided imagery with music to affect the maternal-fetal dialog, The Transitions Maternal and Fetal Wellness Program(tm) (Schwartz & McDonald, 1996). By using this tape, I hoped to positively influence some of the risk factors related to preterm labor and low birth weight. The tape was designed to reduce overall stress, strengthen communication between mother and fetus, and to get mother to center on the here and now. Messages gently alert the mother to the dangers of alcohol, drugs, and smoking, and to the importance of nutrition and exercise.3

Initial anecdotal reports from a group of low socioeconomic mothers have indicated higher birth weights in the mothers exposed to this guided imagery and music (Hetty Watters, 1997). A large multi-center study is being initiated to explore these benefits to various populations. Maternal and neonatal variables will include gestational age, birth weight, APGAR scores, duration of labor, birth complications, the cost of medical care, and maternal and paternal fetal attachment. We know the medical benefits of this type of therapy but proving this in further studies is necessary before we will see large scale use of these therapies.

Notes

1. Despite this particular mother’s own preference for loud rock music, other research reveals the fetal child prefers quieter passages of Mozart and Vivaldi, consonant music over dissonant music, and, obviously, lullabies (For example, Clements, 1977; Montemurro, 1996; Zentner and Kagen, 1998).

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