Symphysis Pubis Dysfunction: Analysis of Risk Factors and Basic Diagnostic Criteria

BACKGROUND: Symphysis pubis dysfunction is a pregnancy complication with significant statistical variations in incidence due to the lack of clear diagnostic criteria and overdiagnosis. One of the causes of this complication is excessive relaxin production, which induces structural changes in the fibrocartilaginous disc and resorption of the symphyseal margins. During normal pregnancy, this discrepancy is insignificant and amounts to 2–3 mm by the end of the third trimester; it is adaptive in nature, while facilitating the unimpeded passage of the fetus through the mother’s birth canal. However, if the pubic joint is excessively relaxed, it becomes unstable, with discomfort and lumbar or pelvic girdle pain appearing. To diagnose subluxation of the symphysis pubis, various provocative tests, echography, and radiography of the pubic joint are performed. However, the degree of discrepancy in the echographic picture rarely correlates with the severity of the clinical picture.

AIM: The aim of this study was to identify risk factors for symphysis pubis dysfunction and assess its ultrasound diagnostic criteria.

METHODS: We analyzed 40 medical histories of pregnant women with symphysis pubis dysfunction and 50 medical histories of those without the pathology. Risk factors were assessed and ultrasound diagnostics of the pubic joint was performed in all women before and after childbirth using Voluson 730 and Logiq 9 expert-class devices in three-dimensional mode with the 5–10 MHz linear sensor.

RESULTS: Most women with symphysis pubis dysfunction were multiparous under 35 years of age. Primiparous women were only diagnosed with grades I and II dysfunction (100%), while 14% of multiparous patients were diagnosed with grade III dysfunction. In patients with symphysis pubis dysfunction, inflammatory diseases of the uterus and appendages, infertility, and polycystic ovary syndrome were more common gynecological pathologies and were detected in 47.5%, 35% and 27.5% of cases versus 14%, 4% and 10% of cases in the control group, respectively (p < 0.05). Grades II and III dysfunction was most often detected in pregnant women with overweight and obesity – in 91.7% of cases (p < 0.05). In all patients with grade I dysfunction, the fetal weight was up to 3,500 g, while in the study groups with grades II and III dysfunction, the baby weighed more than 3,500 g and was large in 66.6% of patients (p < 0.05). During ultrasound examination, 83.3% of patients with grades II and III dysfunction, along with diastasis, revealed symptoms characteristic of inflammation (p < 0.05), and 28% of pregnant women in the control group were diagnosed with pubic symphysis divergence that corresponded to grades I and II dysfunction — 85.7% and 14.3% of cases, respectively. At the same time, no clinical manifestations were detected.

CONCLUSION: Important risk factors for symphysis pubis dysfunction are metabolic and endocrine disorders, inflammatory diseases of the female reproductive organs, repeated childbirth, and fetal weight of over 3,500 g. Ultrasound criteria for diagnosing this condition are not reliable for grade I dysfunction.