The goal of this randomized controlled trial is to assess whether a 12-week anti-inflammatory diet can improve fertility outcomes in women with endometriosis undergoing In Vitro Fertilization (IVF).

The main questions are:

• Does the anti-inflammatory diet reduce the rate of inadequate ovarian response to hormonal stimulation (retrieval of ≤3 oocytes)?
• Does it improve secondary outcomes such as embryo quality, pregnancy rates, inflammation markers, and quality of life?

Researchers will compare two groups:

• Women receiving standard IVF protocols.
• Women undergoing the same IVF protocol plus the anti-inflammatory diet.

Participants will:

• Be randomized into one of the two groups.
• Follow dietary counseling sessions and complete dietary assessments (diet group).
• Provide biological samples (e.g., plasma, vaginal and fecal swabs, and follicular fluid) before and after the dietary intervention to evaluate potential differences in inflammation, hormonal levels, and microbiome composition between the two groups and across timepoints (pre- and post-diet).
• Complete questionnaires on quality of life, sexual function, and symptomatology severity before and after the intervention to assess differences between the two groups and across timepoints.

Women who agree to participate in the study will be randomized into two groups: one group will receive standard IVF protocols, and the other will undergo a 12-week anti-inflammatory diet followed by the standard IVF protocol. In both groups, participants' dietary habits will be monitored throughout the study period to detect any variations. The primary outcome will be to compare the rate of inadequate ovarian response to hormonal stimulation (defined as the retrieval of ≤3 oocytes according to the Poseidon 2016 criteria) in infertile women with endometriosis.

Inclusion Criteria:

• Age < 40 years
• Pregnancy seeking for more than 12 months
• Regular menstrual cycle, i.e. mean cycle interval between 21 and 35 days
• Ultrasonographic diagnosis of ovarian endometriomas or deep peritoneal endometriosis.
• Antral Follicle Counts (AFC) ≥ 5 (no other cause of reduced ovarian reserve).
• Absence of ureteral stenosis or intestinal subocclusive symptoms

Exclusion Criteria:

• Contraindication to pregnancy
• Hydrosalpinx
• Endometriomas with a mean diameter > 4 cm
• Submucosal fibroids or large intramural or subserosal fibroids (≥ 5 cm).
• Doubtful sonographic findings that do not allow to reliably rule out malignancy.
• severe male factor (<1 million sperm/ml)

The treatment will be kept blind for both the medical and laboratory personnel performing the in vitro fertilization procedures. The allocation branch will be revealed to the data manager at the end of data collection related to the primary outcome.