A metaanalysis on alcohol consumption and risk of endometriosis

Fertility awareness methods and waiting conduct in idiopathic infertility: a prospective observational study

Barbato M et al., 2026 · Frontiers in Reproductive Health · Free full text on PubMed Central

Couple infertility is a common clinical condition that is too often treated with assisted reproductive techniques (ARTs) without a proper evaluation of both male and female factors. To improve the likelihood of natural conception, fertility awareness methods (FAMs) are widely used. We performed a multicenter prospective study enrolling couples with primary idiopathic infertility who were seeking natural conception. Participants were followed for 12 months using FAMs, and their outcomes were compared with those of couples who only used ARTs. The aim of our study was to evaluate the pregnancy rate after 12 months among couples with idiopathic infertility using FAMs compared with those who immediately pursued ARTs. We evaluated 41 couples in the FAM group and 56 couples in the ART group. In the FAM group, we reported a pregnancy rate (PR) of 51.22%. Among women aged <34 years, we reported a PR of 90.9%, while it decreased to 36.7% among women aged 35-39 years. In the ART group, 10 couples achieved pregnancy (PR 17.8%). Within this group, we reported a PR of 30% among women aged <34 years and 17.4% among women aged 35-39 years. After 12 months of unprotected intercourse without spontaneous conception in women younger than 35 years or after 6 months in women aged 35-39 years, couples should undergo a complete multidisciplinary diagnostic evaluation involving both the male and female partners. If a diagnosis of idiopathic infertility is established at the end of this process, couples (especially younger ones) may be advised to wait an additional 12 months while using FAMs, as no advantage has been observed with direct access to ARTs. They could then be referred to ART if a spontaneous pregnancy is not achieved during this period.

Risk of endometriosis progression in infertile women trying to conceive naturally or using IVF

Somigliana E et al., 2025 · Human Reproduction · Free full text on PubMed Central

The use of hormonal treatments for endometriosis has increased in recent years. Their effectiveness lies in creating a stable hormonal environment, reducing peripheral estrogen levels, and suppressing ovulation and menstruation. Although these agents do not cure endometriosis and symptoms often return after discontinuation, they effectively relieve pain in most cases and help prevent disease progression or recurrence. Women are therefore typically managed with long-term hormonal treatments, with or without surgery. However, this approach is unsuitable for those seeking natural pregnancy or undergoing IVF, as all hormonal treatments hinder conception. For women pursuing natural pregnancy, these treatments should be discontinued for about 1 year, the time needed to diagnose infertility. However, this suspension exposes women to the risk of recurrence or progression and is therefore clinically acceptable only if the woman has a reasonable likelihood of achieving pregnancy naturally. In women with endometriosis who are infertile and therefore require IVF, ovarian stimulation significantly raises estrogen levels-up to 10 times those of a natural cycle-potentially boosting the risk of endometriosis relapse. Evidence is reassuring on this issue even if some limited data suggest that ovarian stimulation may promote deep invasive endometriosis progression. Overall, physicians and patients must balance the chances of natural or ART-assisted pregnancy against the risk of disease recurrence or progression during treatment discontinuation or IVF. This choice is also complicated by the increased risk of severe pregnancy complications in women with endometriosis, possibly depending on the conception method. This review discusses the available evidence that can be helpful in guiding the decision-making process.

Hormonal imbalance in umbilical vein cord blood of pregnant women with endometriosis: a propensity score-matched analysis

Salmeri N et al., 2025 · Reprod Biol Endocrinol · Free full text on PubMed Central

Ovarian reserve does not influence natural conception: insights from infertile women

Galati G et al., 2024 · Archives of gynecology and obstetrics · Free full text on PubMed Central

There is several albeit not univocal evidence suggesting that ovarian reserve is not related to the chance of natural pregnancy, provided that the remnant follicular pool is sufficient to ensure regular menstrual cycles. Nevertheless, available studies have some methodological limitations, and the issue cannot be considered definitively ascertained. To further address this issue, we retrospectively selected infertile women whose infertility diagnostic work-up was unremarkable (unexplained infertility-cases) and matched them by age and study period to a group of infertile women who were diagnosed with severe male infertility (controls). If ovarian reserve impacts on natural fertility, one had to expect lower ovarian reserve among women with unexplained infertility. Tested biomarkers included AMH, AFC and day 2-3 serum FSH. The primary aim was the frequency of women with serum AMH < 0.7 ng/ml. Two-hundred fifty-two women with unexplained infertility and 252 women with male infertility were included. All biomarkers of ovarian reserve did not differ between the study groups. AMH levels < 0.7 ng/mL were observed in 26 (10%) women with unexplained infertility and 35 (14%) women with male infertility (p = 0.28). The adjusted OR was 0.76 (95% CI: 0.44-1.33). Significant differences did not also emerge when repeating this dichotomous analysis using other biomarkers and other thresholds for the definition of low-ovarian reserve. This study confirms that ovarian reserve is unremarkable to natural conception. Physicians and patients should be aware of this concept to avoid inappropriate counseling and undue clinical decisions.

Modifiable life style factors and risk for incident endometriosis

Hemmert R et al., 2018 · Paediatr Perinat Epidemiol · Free full text on PubMed Central

Caffeine, alcohol, smoking and physical activity are known to alter sex steroid synthesis, which may affect hormone-dependent gynaecologic disease risk, such as endometriosis; however, few studies have assessed life style factors prior to endometriosis diagnosis. Four hundred and seventy three women, ages 18-44 years, underwent laparoscopy or laparotomy, regardless of clinical indication, at 14 clinic sites, 2007-2009. Women with prior surgically confirmed endometriosis were excluded. Life style factors were assessed prior to surgery. Adjusted risk ratios (RR) of endometriosis by caffeine, alcohol, smoking (serum cotinine), and physical activity were estimated, adjusting for age, marital status, education, race/ethnicity, age at menarche, gravidity, BMI, study site, and other life style factors. There were no associations between women with endometriosis and alcohol consumption (RR 0.9, 95% CI 0.7, 1.3), caffeine consumption (RR 1.1, 95% CI 0.8, 1.5), or smoking (serum cotinine <10 vs ≥10 ng/mL; RR 1.0, 95% CI 0.7, 1.6). Similar null findings were found between endometriosis and weekly occurrences of physical activity and total walking, moderate, and vigorous activity; a modest trend was found between total daily sitting time and increased endometriosis risk. This study, which is unique in its capture of life style exposures prior to incident endometriosis diagnosis, largely found no association between alcohol, caffeine, smoking, and physical activity and risk of endometriosis.

Endometriosis, dysmenorrhoea and diet

Hansen SO et al., 2013 · Eur J Obstet Gynecol Reprod Biol

To review the literature on the effects of diet on endometriosis and dysmenorrhoea. A systematic search for trials investigating a relationship between diet and endometriosis/dysmenorrhoea was undertaken, and 23 studies were included in this review. Data on the relationship between diet and endometriosis were limited to 12 trials, three of which were animal studies, resulting in a total of 74,708 women. One large study (n=70,709) found a relatively strong association between endometriosis and trans-fatty acid consumption, and a lower risk of endometriosis with increased consumption of long-chain omega-3 fatty acids. The latter finding was also supported by smaller studies. No further dietary recommendations for reducing the risk of endometriosis were possible, and results for intake of vegetable, fibre and fruit were equivocal. The relationship between diet and dysmenorrhoea was investigated in 11 trials with different designs, including a total of 1433 women. Intake of fish oil seemed to reduce dysmenorrhoea. The literature on endometriosis and dysmenorrhoea in relation to diet is sparse, yielding equivocal results on specific elements. Overall, however, the literature suggests that specific types of dietary fats are associated with endometriosis and/or dysmenorrhoea, thereby indicating that there may be modifiable risk factors. Further research is recommended on both subjects.

In utero exposures and endometriosis: the Endometriosis, Natural History, Disease, Outcome (ENDO) Study

Wolff EF et al., 2013 · Fertility and sterility

To assess in utero exposures and the odds of an endometriosis diagnosis. Matched cohort design. Fourteen participating clinical centers in geographically defined areas in Utah and California. PATIENT(S): Operative cohort comprised 473 women undergoing laparoscopy/laparotomy, and an age- and residence-matched population cohort comprising 127 women undergoing pelvic magnetic resonance imaging (MRI), 2007-2009. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Women completed standardized interviews before surgery or MRI regarding in utero exposures: mothers' lifestyle during the index pregnancy, and the index woman's gestation and birth size. Endometriosis was defined as visually confirmed disease in the operative cohort, and MRI visualized disease in the population cohort. The odds of an endometriosis diagnosis and corresponding 95% confidence intervals (CI) were estimated for each exposure by cohort using logistic regression and adjusting for current smoking, age at menarche, body mass index, and study site. RESULT(S): Endometriosis was diagnosed in 41% and 11% of women in the operative and population cohorts, respectively. In the primary analysis, adjust odds ratios (AORs) were elevated for maternal vitamin usage (1.27; 95% CI, 0.85-1.91), maternal cigarette smoking (1.16; 95% CI = 0.61-2.24), and low birth weight (1.1; 95% CI, 0.92-1.32). Reduced odds were observed for maternal usage of caffeine (0.99; 95% CI, 0.64-1.54), alcohol (0.82; 95% CI, 0.35-1.94), paternal cigarette smoking (0.72; 95% CI, 0.43-1.19), and preterm delivery (0.98; 95% CI, 0.47-2.03). Sensitivity analyses mostly upheld the primary results except for a decreased AOR for preterm birth (0.41; 95% CI, 0.18-0.94) when restricting to visualized and histologically confirmed endometriosis in the operative cohort. CONCLUSION(S): In utero exposures were not statistically significantly associated with the odds of an endometriosis diagnosis in either cohort.

Fruit and vegetable consumption and risk of endometriosis

Harris HR et al., 2018 · Human reproduction (Oxford, England) · Free full text on PubMed Central

Is there an association between intake of fruits and vegetables and risk of laparoscopically confirmed endometriosis? Higher intake of fruits, particularly citrus fruits, is associated with a lower risk of endometriosis. Two case-control studies have examined the associations between fruit and vegetable intake and endometriosis risk with contrasting results. Diets rich in fruits and vegetables include higher levels of pro-vitamin A nutrients (alpha-carotene, beta-carotene, beta-cryptoxanthin) and women with endometriosis have been reported to have lower intake of vitamin A than women without endometriosis. STUDY DESIGN SIZE, A prospective cohort study using data collected from 70 835 premenopausal women from 1991 to 2013 as part of the Nurses' Health Study II cohort. PARTICIPANTS/MATERIALS, SETTING, Diet was assessed with a validated food frequency questionnaire (FFQ) every 4 years. Cases were restricted to laparoscopically confirmed endometriosis. Cox proportional hazards models were used to calculate rate ratios (RR) and 95% CI. MAIN During 840 012 person-years of follow-up, 2609 incident cases of laparoscopically confirmed endometriosis were reported (incidence rate = 311 per 100 000 person-years). We observed a non-linear inverse association between higher fruit consumption and risk of laparoscopically confirmed endometriosis (Psignificance of the curve = 0.005). This inverse association was particularly evident for citrus fruits. Women consuming ≥1 servings of citrus fruits/day had a 22% lower endometriosis risk (95% CI = 0.69-0.89; Ptrend = 0.004) compared to those consuming <1 serving/week. No association was observed between total vegetable intake and endometriosis risk. However, women consuming ≥1 servings/day cruciferous vegetables had a 13% higher risk of endometriosis (95% CI = 0.95-1.34; Ptrend = 0.03) compared to those consuming <1 serving/week. Of the nutrients examined, only beta-cryptoxanthin intake was significantly associated with lower endometriosis risk (RR fifth quintile = 0.88; 95% CI = 0.78-1.00; Ptrend = 0.02). LIMITATIONS Some error in the self-reporting of dietary intake is expected, however, use of a validated FFQ and examining diet prospectively across multiple time points, make it unlikely that this non-differential misclassification strongly influenced the results. Our findings suggest that a higher intake of fruits, particularly citrus fruits, is associated with a lower risk of endometriosis, and beta-cryptoxanthin in these foods may partially explain this association. In contrast to what we hypothesized, consumption of some vegetables increased endometriosis risk which may indicate a role of gastrointestinal symptoms in both the presentation and exacerbation of endometriosis-related pain; however, it is not clear what components of these foods might underlie the observed associations. Future studies examining dietary patterns that consider different combinations of food intake may help clarify these associations. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by research grants HD4854, HD52473 and HD57210 from the Eunice Kennedy Shriver National Institute of Child Health and Human Development, and grant P30 DK046200 from the National Institute of Diabetes and Digestive and Kidney Diseases. The Nurses' Health Study II is supported by the Public Health Service grant UM1 CA176726 from the National Cancer Institute, National Institutes of Health. HRH is supported by the National Cancer Institute, National Institutes of Health (K22 CA193860). No competing interests. n/a.