{Reference Type}: Practice Guideline {Title}: [How to diagnose menopause? Postmenopausal women management: CNGOF and GEMVi clinical practice guidelines]. {Author}: Rousset-Jablonski C; {Journal}: Gynecol Obstet Fertil Senol {Volume}: 49 {Issue}: 5 {Year}: 05 2021 {Factor}: 1.058 {DOI}: 10.1016/j.gofs.2021.03.011 {Abstract}: The diagnosis of menopause is sometimes difficult. The objective of this chapter is to describe the process of diagnosing menopause in a physiological situation, then in different clinical situations: women using hormonal contraception (per os, implant or intrauterine device), women with a history of hysterectomy, women previously treated for cancer. A review of the literature was carried out via Pubmed, Medline and Cochrane Library. The recommendations of international societies were also taken into account: International Menopause Society (IMS) https://www.imsociety.org, European Menopause and Andropause Society (EMAS) https://www.emas-online.org. In a classic situation, the diagnosis of menopause is a clinical diagnosis, made retrospectively, based on a 12-month period of consecutive amenorrhoea in a compatible age group (after 45 years of age). No hormonal dosage or imaging is indicated to make a diagnosis of menopause in a classic situation. In women using oestroprogestogen or progestative-only-pill contraception, implant, or Levonorgestrel-intrauterine device (LNG IUD), hormonal assays or pelvic ultrasound are neither recommended to make a diagnosis of menopause (grade C), nor to decide to stop contraception (grade C). The proposed strategy is the discontinuation of oral contraception, removal of the implant or LNG-IUD, and clinical follow-up (occurrence of amenorrhea) (expert opinion). In women with a history of hysterectomy, in the absence of evaluable clinical symptoms (amenorrhea), a repeat FSH≥40 combined with low estradiol (<20pg/ml) at least 3 months after the procedure could be a diagnostic orientation towards menopausal status. After cancer, in women who have received gonadotoxic treatment, the classic clinical criteria of 12 months of amenorrhea cannot be used to make a diagnosis of menopause with certainty (expert opinion). No further examination can be recommended to make a definite diagnosis of menopause (expert opinion). In breast cancer, the hormonal status to be taken into account when choosing initial hormone therapy is the one found before starting any treatment. If at the time of diagnosis of breast cancer the menopausal status is not known due to hormonal contraception, it is preferable to consider the patient as non-menopausal by default for the choice of hormone therapy for the cancer.