NEW YORK (Reuters Health) – In some teenage girls, very painful menstrual periods that interfere with daily life may signal an increased risk of developing the most extensive form of endometriosis, a preliminary study suggests.

In a study of 229 women undergoing surgery for endometriosis, French researchers found that those with the most extensive form — known as deep infiltrating endometriosis (DIE) — were more likely to have had particularly painful periods as teenagers.

As a group, they were four times as likely as women with non-DIE endometriosis to have used birth control pills to treat severe menstrual pain before the age of 18. And they were 70 percent more likely to say they'd missed school days because of menstrual symptoms.

The findings, published in the journal Fertility and Sterility, suggest that such problems in adolescence can sometimes predict a later diagnosis of DIE.

In endometriosis, pieces of the tissue that lines the uterus (the endometrium) also grow outside the organ — often on the ovaries, the fallopian tubes or elsewhere in the pelvis. like the endometrium, this misplaced tissue changes with each menstrual cycle, thickening and then breaking down and bleeding.

This leads to a buildup of adhesions, or scar tissue, outside the uterus, with symptoms including pelvic pain and heavy, painful menstrual periods. Some women also have difficulty becoming pregnant.

There are three forms of endometriosis: superficial endometriosis, ovarian endometriomas and DIE, with the latter being the most extensive. Women with DIE usually have adhesions in multiple areas of the pelvis, including the vagina, bladder, bowel and the ligaments attaching the uterus to the pelvis.

Endometriosis can be tricky to diagnose, and many girls and women go years before a diagnosis.

The condition may, for instance, be mistaken for other causes of pelvic pain, like ovarian cysts, pelvic inflammatory disease or, depending on the symptoms, irritable bowel syndrome. In addition, while a pelvic exam or ultrasound test are often used to help diagnose endometriosis, the only way to definitively diagnose it is through minimally invasive laparoscopic surgery to take a tissue sample.

Compared with the other forms of endometriosis, DIE appears to have a longer delay to diagnosis.

So for the new study, Dr. Charles Chapron and colleagues at Universite Paris Descartes tried to find out whether women undergoing surgery for endometriosis had any early symptom history that was associated with a greater likelihood of having

The study included 229 women who had surgery at a single medical center between 2004 and 2009; 43 percent had DIE, while the rest had the less-extensive forms of endometriosis. all of the women were interviewed about their symptom history; their average age at the time of surgery was 32.

Overall, 58 percent of women with DIE had ever been prescribed birth control pills to treat severe menstrual pain, versus 26 percent of women with non-DIE forms. Similarly, 21 percent of women with DIE had their first prescription before the age of 18, compared with 6 percent of those in the non-DIE group.

When it came to missed school days, 38 percent of DIE patients said they'd had absences due to menstrual symptoms, versus one-quarter of women in the non-DIE group.

Women with DIE were also more likely to report a family history of endometriosis; 13 percent did, compared with just under 5 percent of women with non-DIE endometriosis.

The study has a number of limitations, including the fact that it surveyed women at one time point and asked them to recall symptoms from adolescence. a study that followed young women over time to see whether symptoms predicted a later diagnosis of DIE would be more informative.

These findings now set the groundwork for such a long-term study, Chapron told Reuters Health in an email.

but the "crux of the issue," he noted, is whether diagnosing endometriosis earlier will eventually lead to fewer cases of DIE and less need for surgery.

"Today, there is no effective way to prevent the progression of endometriosis to its most severe stage, DIE," Chapron said.

And the current results, he noted, suggest that treating severe menstrual pain with birth control pills does not prevent progression to DIE, as a history of such treatment was linked to the condition. Chapron also pointed out, however, that this does not mean that birth control pills contributed to the development of DIE either.

Still, even though it is not clear whether progression to DIE can be prevented, an earlier diagnosis of endometriosis would at least allow girls and women to know the cause of their symptoms.

according to Chapron and his colleagues, girls and women with severe menstrual pain that does not respond to pain relievers like ibuprofen should see their doctors, and, if appropriate, be evaluated for endometriosis.

Besides painkillers and birth control pills, non-surgical treatments for endometriosis include several types of hormonal medications that inhibit the growth of the endometrial tissue.

SOURCE: link.reuters.com/xam46q Fertility and Sterility, online November 11, 2010.