Pelvic venous system comprises of a rich network of anastomosed collecting vessels encompassing mainly the uterine, ovarian and internal iliac veins.
Pelvic congestion syndrome (PCS) is a condition involving dilated/varicose veins in the pelvis, typically causing chronic non-cyclical abdominal pain for over six months duration in the absence of known pelvic pathology, with a considerable negative effect on quality of life. Though over 30% pelvic pain is caused by PCS, diagnosis is often delayed.
Pain from PCS is usually worsened during menstruation, intercourse, bladder or bowel movements and gestation. Clinical manifestations such as menorrhagia, dysmenorrhea, dyspareunia, post coital ache, severe ovulation pain, rectal pain, bladder irritability, left lateral vaginal tenderness, pelvic pressure/discomfort on prolonged sitting or standing, pain in the back or hip can result from PCS.
This can significantly impact the daily lives of those living with it. PCS is often misdiagnosed as endometriosis due to similarities in presenting symptoms.
The aetiology of PCS is thought to be pelvic venous hypertension due to incompetent valves. There is a positive association between oestrogen levels and varicose veins suggesting that higher levels of this hormone increase venous dilation.
The pathophysiological mechanism of pain in PCS is believed to be engorgement of pelvic veins, resulting in the compression of adjacent pelvic organs. Studies have demonstrated that increased serum oestrogen is directly proportional to higher levels of patient pain.
Transvaginal scan (TVS) is the most commonly used imaging modality to identify pelvic pathology, being minimally invasive, non-ionising, cost-effective and readily available. As pelvic pain is one of the most common reasons for pelvic ultrasound referral, TVS is an effective diagnostic tool for PCS, and the role of TVS is increasing in the identification of this condition.
Dilation of pelvic veins is measured based on diameter, with the generalised normal range being between 2-4mm. A reference range has been established for uterine vein diameter of both nulliparous and parous women. For premenopausal nulliparous women, veins measuring 6mm and above can undoubtedly be considered
as dilated.
The treatment of PCS can be conservative. However, modern minimally invasive endovascular treatments are highly effective and shown to result in alleviation of symptoms, greatly improving their quality of life in a low-risk day case setting.
When pelvic varicosities are not assessed in routine pelvic ultrasounds, the identification of PCS is prolonged, leading to unnecessary patient suffering. Among the diverse aetiologies, PCS is a common cause in approximately one third of patients with chronic pelvic pain.
Due to the extensive range of gynaecological causes of pain and lack of knowledge in many of these areas, delay in diagnosis can also result in investigation in the wrong direction. These factors reinforce the importance of assessing and measuring veins in the pelvis in routine transvaginal scans.
Research into PCS in nulliparous females is limited to small number of case reports. However, recent studies increasingly report existence of this condition in young, nulliparous women, despite its association with pregnancy and increased age. The incidence of PCS increases with age in pre-menopausal women, peaking at 41-50 years old. Further investigation into this phenomenon would be beneficial in increasing clinicians’ understanding of PCS and its occurrence in younger populations, improving their ability to diagnose and effectively treat the condition.
Pelvic congestion syndrome should not be dismissed as a differential diagnosis in those presenting with chronic pelvic pain, especially on the basis of parity.
Preliminary data from our unit showed that about 40% of patients with PCS on pelvic scan were nulliparous and under 35 years of age with the majority being referred for suspected endometriosis. About 50% of young nulliparous patients who were referred for pain symptoms were found to have PCS on pelvic scan.
A pelvic scan is an essential investigation that can initially suspect pelvic congestion as well as reliably rule out all gynaecological causes for chronic pelvic pain such as endometriosis, pelvic inflammatory disease, adenomyosis and fibroids etc.
Such a scan report would direct the treatment journey of these women in the right direction as PCS is one of the most underdiagnosed, misdiagnosed, ignored, and undertreated gynaecological if not medical conditions in women.
References available on request
Author competing interests – nil