Pelvic pain may be common among reproductive-age women

A high proportion of reproductive-age women may be experiencing pelvic pain that goes untreated, according to a study by researchers from the National Institutes of Health and the University of Utah School of Medicine.

The research team, lead by Karen Schliep PhD of the Division of Intramural Population Health Research at NIH’s Eunice Kennedy Shriver National Institute of Child Health and Human Development, surveyed more than 400 women who were scheduled to undergo surgery or imaging for such reasons as infertility, menstrual irregularities, tubal sterilisation, or pelvic pain.

As the researchers expected, reports of pain were highest for women diagnosed with endometriosis. However, one-third of those without any pelvic condition also reported a high degree of ongoing pain or pain recurring during the menstrual cycle.

Why study pelvic pain and endometriosis?

Dr Karen Schliep, Division of Intramural Population Health Research at NIH's Eunice Kennedy Shriver National Institute of Child Health and Human Development

Although endometriosis is known to be a major contributor to pelvic pain, there is limited knowledge in regards to how pelvic pain associated with endometriosis differs from pelvic pain associated with other gynaecologic conditions or among women with no gynaecologic pathology.

It is important that we improve our understanding of these relationships if we wish to improve care for women experiencing pelvic pain

said Dr Schliep.

The study, published in Human Reproduction [1], enrolled 473 women ages 18 to 44 years at 14 surgical centres in Salt Lake City and San Francisco.

The women were set to undergo either laparoscopy or laparotomy because of pain for a mass or lump in the pelvic region, infertility, menstrual irregularities, or for tubal sterilisation

In an interview before their surgery, the women were asked about the kind of pain they had experienced in the past six months, along with its severity. In all, the women were asked if they had more than 17 specific types of pain related to sexual intercourse, their menstrual period, urination or bowel elimination, or other pain, such as muscle or joint pain or migraine headaches. In addition, they were asked to indicate on diagrams of the pelvic area and of a standing female figure where they felt pain (see below).

Women with endometriosis experience more pelvic pain

More than 30 percent of the women reported that they were experiencing chronic pain and cyclic pain — coinciding with an interval during their monthly menstrual cycle — lasting six months or more.

This 30 percent included not only women with pelvic disorders, but also those without any pelvic condition. In addition, regardless of the reason they had surgery or of their diagnosis after the operation, only three percent of the total study population reported having none of the 17 types of pain, while over 60 percent reported six or more types of pain.

Women were asked to indicate on a diagram the areas where they felt pain. The colour-coded blocks show the number of women reporting pain, ranging from the least pain (top block) to the most pain (bottom block). Most women reported pain in the pelvic-abdominal area. The greatest number of women reporting pain in the pelvic-abdominal area were those later diagnosed with endometriosis.

Among the study participants, approximately 40 percent were diagnosed with endometriosis and 31 percent with other conditions, including uterine fibroids, ovarian cysts, and tumours. Nearly 29 percent had not been diagnosed with any pelvic conditions.

Similar to WERF’s Global Study on Women’s Health (GSWH) [2], women diagnosed with endometriosis experienced the most chronic pain; in this case slightly more than 44 percent, compared to about 30 percent of women without any pelvic condition.

And, just as in WERF’s GSWH, women with endometriosis were more likely to experience pain during intercourse, menstrual cramping, and pain with bowel elimination. They also were more likely to report vaginal pain and pain in the pelvic-abdominal area.

Research needed in type of endometriosis pain

Clinicians need to be made aware that having their patients complete detailed pain assessment questionnaires, such as those provided by the International Pelvic Pain Society, may improve their own understanding of the relationships between pain type, severity, location, and gynaecologic health.

This understanding can in turn improve their clinical management of pain among affected women. Women also need to be educated that they should speak up if they are experiencing pelvic pain so that clinicians can manage their symptoms and treat any underlying conditions, such as endometriosis, that may be causing the pain.

said Dr Schliep.

References

Schliep et al. Pain typology and incident endometriosis. Hum Reprod 2015 [Epub ahead of print]
Nnoaham et al. Impact of endometriosis on quality of life and work productivity: a multicenter study across ten countries. Fertil Steril 2011;96(2):366-373 [FREE ACCESS]