Sudden onset pain is often caused by bleeding from the ovary which tends to occur during ovulation (release of egg from the ovary) or following a rupture of ovarian cyst. The pain could be severe, but it often resolves after a few hours without any treatment. Occasionally bleeding from the ovary could be severe leading to a significant blood loss. In rare cases emergency surgery is needed to stop the bleeding. Ovulation and bleeding from the ovary can be reliably detected on ultrasound scan which helps to identify the cause of the problem without delay and facilitate appropriate management.

Another common cause of acute pain is twisting of the ovary which is usually referred to as ovarian torsion. This usually happens when the ovaries are enlarged due to the presence of an ovarian cyst. Ovarian torsion may result in a loss of ovary due to compromise in blood supply. In view of that a prompt diagnosis and treatment are important to save the ovary. Ultrasound in the optimal method to diagnose ovarian torsion and initiate appropriate treatment without delay. In some cases of torsion ultrasound-guided puncture and aspiration of cyst fluid are sufficient to resolve the problem without the need for emergency surgery.

Pelvic infection is another cause of acute pelvic pain. The diagnosis of infection is mainly based on symptoms such as fever and abnormal results of a blood test. Ultrasound is helpful, however, to assess the severity of infection and to exclude other abnormalities which may present in a similar way. Ultrasound can also be used to drain pus from a pelvic abscess which helps to treat infection more effectively.

Acute pelvic pain can also be caused by non-gynaecological conditions such as ureteric stone or appendicitis. We examine urinary bladder, pelvic ureters and kidneys routinely in every woman who presents with pelvic pain which enables us to detect stones in the urinary tract. Normal appendix is difficult to see on ultrasound scan, but in women with inflamed appendix the diagnosis of appendicitis can be made in most cases.

There are several conditions that could cause prolonged pain which does not go away or keeps coming back. In some women, the pain is present most of the time, whilst other women may experience pain only at a particular time during the menstrual cycle. Constant pain could be caused by pelvic adhesions which could form following surgery or as a result of pelvic infection. Pain could also be triggered by physical activity or sexual intercourse.

In general, adhesions cause the pelvic organs to stick together, which can be detected on ultrasound scan by applying gentle pressure with the ultrasound probe during the examination. Sometimes adhesions can cause blockage of Fallopian tubes. This makes them swell with fluid which helps to see them on ultrasound scan. Fluid can become trapped within severe adhesions which makes it relatively easy to see them on scan.
Chronic pelvic pain can also be caused by large ovarian cysts or fibroids. Women affected by these conditions often describe their pain as ‘pressure pain’.

Menstrual periods can trigger strong uterine contractions which makes them painful. This is often a problem in young teenage girl who sometimes experience debilitating pain during menstruation. Ultrasound findings are usually normal, but sometimes period pains could be caused by congenital abnormalities of the uterus which can be detected on the examination.

Later in life heavy periods can also cause strong uterine contractions which makes them painful. Heavy periods are often caused by uterine abnormalities such as fibroids or adenomyosis which are described in more detail in the section ‘Menstrual problems’. Endometriosis is the most important cause of period pains and is described in a separate section. Another less known cause of period pains is Accessory Cavitated Uterine Malformation (ACUM) which is described in more detail in the section on Congenital Uterine Anomalies.