Quantification of benefits and harms of medical interventions should be based on high-quality evidence, which is not always the case in the endometriosis field. In many clinical circumstances, healthcare decisions in women with endometriosis are taken based on suboptimal evidence or on evidence of coexistence of benefits and harms that must be balanced. In these conditions, it is important to avoid or reduce the use of low-value care, i.e. interventions with defined harms and uncertain benefits, or whose effectiveness is comparable with less expensive alternatives. In particular, we suggest that: (i) non-surgical diagnosis based on symptoms, physical findings and transvaginal ultrasonography is possible in most women with symptomatic endometriosis. Thus, except in doubtful cases, laparoscopy should be intended for surgical treatment, not for diagnostic purposes: early diagnosis and diagnostic laparoscopy are not synonymous; (ii) future trials on new drugs for endometriosis should address those outcomes that are most important to patients, should be designed as superiority trials and should include a progestin or an estrogen-progestin as a comparator. Moreover, limitation of repetitive surgery for recurrent endometriosis is among the objectives of long-term medical treatment; (iii) indications for surgery should be the result of a balance between demonstrated benefits in terms of fertility enhancement and pain relief, specific risks associated with excision of different types of endometriotic lesions, cost-effectiveness and patient preference after detailed information; (iv) physicians, health professionals and policy makers should discriminate between screening for and diagnosis of endometriosis. Limited peritoneal foci, which are frequently observed also in asymptomatic women, regress or remain stable in about two thirds of cases. Therefore, the theoretical premises for a screening campaign are currently unclear; (v) physicians should develop the ability to effectively communicate quantitative information based on international guidelines and systematic literature reviews. This will assist a woman's understanding of the interaction between the evidence and her priorities, facilitating the transition towards value-based medicine.

2,3,7,8-Tetrachlorobenzo-p-dioxin (TCDD), a halogenated compound that binds the aryl hydrocarbon receptor, is a by-product of numerous industrial processes including waste incineration. Studies in rats and monkeys suggest that TCDD may affect ovarian function. We examined the relationship of TCDD and age at menopause in a population of women residing near Seveso, Italy, in 1976, at the time of a chemical plant explosion. We included 616 of the women who participated 20 years later in the Seveso Women's Health Study. All women were premenopausal at the time of the explosion, had TCDD levels measured in serum collected soon after the explosion, and were > or = 35 years of age at interview. Using proportional hazards modeling, we found a 6% nonsignificant increase in risk of early menopause with a 10-fold increase in serum TCDD. When TCDD levels were categorized, compared with women in the lowest quintile (< 20.4 ppt), women in quintile 2 (20.4-34.2 ppt) had a hazard ratio (HR) of 1.1 (p = 0.77), quintile 3 (34.3-54.1 ppt) had an HR of 1.4 (p = 0.14), quintile 4 (54.2-118 ppt) had an HR of 1.6 (p = 0.10), and quintile 5 (> 118 ppt) had an HR of 1.1 (p = 0.82) for risk of earlier menopause. The trend toward earlier menopause across the first four quintiles is statistically significant (p = 0.04). These results suggest a nonmonotonic dose-related association with increasing risk of earlier menopause up to about 100 ppt TCDD, but not above.