This study aims to investigate the effect of primary dysmenorrhea on the activity of the abdominal and back muscles in young adult females.

PD is highly prevalent in females, which directly influences their quality of life, physical function and performance. A study conducted in Palestine has shown that over half of university students with dysmenorrhea tend to skip university lectures due to painful menses.

PD is commonly associated with visceral pain and various musculoskeletal symptoms, including abdominal and back pain (Yacubovich et al., 2019). This can reduce the maximum voluntary contraction of the affected muscles, compromising their ability to provide adequate support and stability (Merkle et al., 2020). Persistent pain can disrupt postural stability and balance, raising the risk of injury by compromising stability and muscle function.

Research highlights the impact of primary dysmenorrhea (PD) on muscle function, particularly in the abdominal and back muscles, contributing to pain and reduced stability. Oladosu et al. (2018) found that abdominal muscle activity precedes menstrual pain, suggesting a neuromuscular link. Similarly, Karakus et al. (2022) and Álvarez et al. (2024) reported altered activation and reduced endurance in stabilizing muscles, including the transversus abdominis, obliques, and lumbar multifidus, with muscle thinning that may impair spinal stability. These studies emphasize PD's effect on muscle function, but further research is needed to explore variations across severities and guide effective treatments.

When these weakened muscles because of dysmenorrhea are subjected to increased or sudden activity during daily living tasks, such as lifting, bending, or other physical exertions, the risk of injury to the structures they are designed to protect is significantly heightened (Escamilla et al., 2010; Polat et al., 2022).

However, to the best of the authors' knowledge, no research has yet explored the relationship of abdominal and back muscle activity patterns to PD and their variations across different severities of dysmenorrhea, which directly contributes to females' quality of life.

Understanding this association could have significant clinical implications and contribute to new knowledge that helps physical therapists determine the need for custom-designed prevention and treatment programs for females with PD. By raising awareness of the potential musculoskeletal risks associated with PD, this study emphasizes the importance of minimizing strenuous activities during menstruation to reduce muscle strain or injury, ultimately enhancing overall health and well-being during this period.

Inclusion Criteria:

• All females clinically diagnosed with PD, as confirmed and referred by a gynecologist.
• Age ranges from 18 to 25 years.
• BMI ranges from 20 to 25 kg/m2 .
• Onset of menstrual pain 6-24 months after menarche.
• Having a regular menstrual cycle (28 ± 7 days with no intermittent bleeding).
• Their PD symptoms will be determined according to the WaLLID questionnaire and will be classified into mild PD (1-4), moderate PD (5-7), severe PD (8-12).
• All participants are virgins.

Exclusion Criteria:

• Menstrual irregularity.
• Use of antidepressant or steroid drugs.
• Secondary dysmenorrhea.
• Musculoskeletal problems in the abdominal region, pelvic region, or spine.
• Surgical history involving the abdominal region, pelvic region, or spine in the last year.
• Any psychiatric or gynecological problems.

Young females with primary dysmenorrhea

Young adult females with primary dysmenorrhea