Literature Review: The Impact of Fear and Pregnancy-Related Pelvic Girdle Pain on the Pelvic Floor and Birth Outcomes

Pregnancy-related pelvic girdle pain (PGP) is a common condition that affects many pregnant women, causing discomfort, reduced mobility, and psychological distress. Recent research has highlighted the connection between fear, pain, and the pelvic floor, suggesting that fear-related behaviors not only perpetuate pain but also impact the pelvic floor's function during birth. This review explores the latest findings on the role of fear in PGP and how it influences pelvic floor function, while also discussing how physical therapy (PT) interventions can address these complex issues to improve maternal outcomes.

Pregnancy-Related Pelvic Girdle Pain (PGP)

PGP refers to pain experienced in the pelvic region, including the sacroiliac joints and pubic symphysis, often radiating to the lower back, hips, and thighs. The prevalence of PGP during pregnancy ranges from 20-40%, with severity varying from mild to debilitating. While hormonal changes in progesterone and estrogen [not relaxin], mechanical stress from the growing fetus, and postural adaptations with muscular imbalances are contributors, psychosocial factors such as fear, stress, and anxiety also play a crucial role in the persistence and severity of PGP symptoms.

Fear-Avoidance Behaviors in PGP

The role of fear in pain perception and chronicity is well-documented across various musculoskeletal conditions, including pregnancy-related PGP. Fear-avoidance behavior occurs when an individual begins to avoid certain movements or activities due to fear of pain or further injury. This avoidance can lead to deconditioning, compensatory movement patterns, and increased muscle tension, all of which can exacerbate pain and dysfunction.

A 2020 study by Elden et al. examined fear-avoidance behaviors in pregnant women with PGP and found that higher levels of fear were significantly associated with increased pain intensity and functional limitations. These findings align with the fear-avoidance model, which suggests that fear of pain leads to avoidance behaviors that result in muscular dysfunction and altered biomechanics, perpetuating the pain cycle.

The Role of Fear and PGP in Pelvic Floor Dysfunction

The pelvic floor plays a critical role in stabilizing the pelvis, supporting the growing fetus, and facilitating childbirth. However, heightened fear and anxiety can directly affect the pelvic floor muscles, leading to dysfunction in two distinct ways:

Increased Tension: Fear, anxiety, and stress can trigger protective muscle guarding, where pelvic floor muscles become overly tense and hyperactive. This tension can lead to reduced flexibility, impairing the pelvic floor’s ability to lengthen and relax during childbirth. This inability to relax contributes to longer labor times and increased risk of perineal tearing.


Altered Pelvic Support: On the other hand, avoidance of physical activity due to fear can cause overcompensation or underutilization of certain muscles. This can lead to overworked muscles becoming tense and muscles that would normally be working deconditioned. This imbalances can lead to poor load distrubution across the pelvis, hips and spine resulting in a higher likelihood of further pain and possible injury.

A 2021 study by Vleeming et al. demonstrated that women with high levels of PGP and fear were more likely to experience pelvic floor dysfunction postpartum, suggesting a direct relationship between chronic pain, fear-avoidance behaviors, and impaired pelvic floor function.

Fear, PGP, and Birth Outcomes

Fear of childbirth, known as tocophobia, is common among pregnant women and has been associated with negative birth outcomes such as prolonged labor, increased medical interventions, and higher rates of cesarean sections. For women with PGP, fear of pain and movement can amplify these concerns, leading to increased muscle tension and impaired pelvic mechanics during labor.

The pelvic floor muscles must relax and stretch to allow the baby to pass through the birth canal during the second stage of labor. However, heightened fear and muscle guarding in response to pain may interfere with this process, contributing to complications during delivery. A 2023 study by Nygaard et al. found that women with severe PGP and fear of childbirth had a higher incidence of prolonged labor and instrumental deliveries (such as forceps or vacuum-assisted births).

Physical Therapy’s Role in Managing PGP and Fear

Physical therapy (PT) offers a multifaceted approach to managing PGP, addressing both the physical and psychological aspects of pain. By targeting the underlying compensatory motor patterns and dysfunctional movement strategies associated with pain and fear, PT can help pregnant women regain mobility, strength, and confidence in their bodies. Key components of PT for PGP include retraining compensatory motor patterns, graded exposure to feared movements, and building strength and coordination in the supporting muscles of the pelvis.

1. Retraining Compensatory Motor Patterns

As a protective response to pain, many pregnant women with PGP develop compensatory motor patterns to avoid painful movements. These compensations can lead to abnormal loading of the pelvis and surrounding structures, contributing to further dysfunction and instability. Physical therapists work to retrain these faulty movement patterns, helping women regain normal movement mechanics.

Through techniques such as neuromuscular re-education and manual therapy, PTs can help reduce muscle guarding and retrain the body to move more efficiently, reducing the strain on the pelvis and pelvic floor. This retraining is essential not only for alleviating pain during pregnancy but also for preparing the pelvic floor and surrounding muscles for the demands of labor.

2. Graded Exposure to Feared Movements

For many women with PGP, certain movements—such as walking, bending, or getting out of bed—are associated with fear of pain or injury. Graded exposure is a therapeutic approach that involves gradually reintroducing these movements in a controlled and supportive environment, helping women overcome fear-avoidance behaviors. This process is designed to desensitize the nervous system and rebuild confidence in the body’s ability to perform everyday activities without pain.

A 2022 study by Bakker et al. found that women who underwent a PT program incorporating graded exposure experienced significant reductions in PGP intensity and disability. The study also noted improvements in mental health and reductions in fear-avoidance behaviors, highlighting the importance of addressing both physical and psychological factors in PGP management.

3. Building Strength and Coordination in Supporting Muscles

While pelvic floor muscles play a central role in pelvic stability, other muscles that support the pelvis—such as the gluteal muscles, hip flexors, and core muscles—also contribute to load management and force distribution across the pelvic girdle. In women with PGP, these muscles often become weak or poorly coordinated due to pain and altered movement patterns.

Physical therapy focuses on strengthening and coordinating the muscles around the pelvis to improve stability and reduce pain. By ensuring proper load distribution across the pelvis, these interventions can reduce the excessive or insufficient force closure of the pelvic joints, which is often a contributing factor to PGP. Strengthening the gluteal muscles, for example, helps to offload the sacroiliac joints, while core stability exercises improve overall pelvic control.

A 2023 study by Hilde et al. demonstrated that women who participated in a PT program targeting pelvic and hip muscle strength and coordination experienced significant reductions in PGP symptoms, improved functional mobility, and better birth outcomes compared to those who received standard prenatal care.

Conclusion

Pregnancy-related pelvic girdle pain is a multifaceted condition influenced by both physical and psychological factors, with fear playing a central role in the persistence of pain and its impact on pelvic floor function. Physical therapy offers an effective approach to managing PGP by addressing the underlying compensatory motor patterns, reducing fear-avoidance behaviors through graded exposure, and building strength and coordination in the muscles that support the pelvis. By targeting these elements, PT not only alleviates pain but also prepares the body for the physical demands of labor, improving both maternal well-being and birth outcomes.

References:

Elden, H., et al. (2020). "Fear-Avoidance Beliefs and Pelvic Girdle Pain in Pregnancy: A Longitudinal Study." Journal of Musculoskeletal Research.

Vleeming, A., et al. (2021). "Pregnancy-Related Pelvic Girdle Pain: Relationship to Pelvic Floor Dysfunction." European Journal of Obstetrics and Gynecology.

Nygaard, I., et al. (2023). "Impact of Pelvic Girdle Pain and Fear of Childbirth on Labor and Delivery Outcomes." Birth: Issues in Perinatal Care.

Bakker, M., et al. (2022). "Graded Exposure Therapy for Fear of Movement in Pregnant Women with Pelvic Girdle Pain: A Randomized Controlled Trial." Journal of Pain Research.

Hilde, G., et al. (2023). "Effectiveness of a Strength and Coordination Program for Women with Pelvic Girdle Pain During Pregnancy." Journal of Physical Therapy Science.