ABSTRACT
Orally active aromatase inhibitors [AIs] have gained attention for treatment of infertile women with endometriosis in whom aromatase p450 is aberrantly expressed. This review aimed to critically appraise and summarize the available evidence concerning the use of AIs for management of endometriosis-associated infertility. PubMed was searched to May 2015 with the following key words: endometriosis, infertility and aromatase. Priority was given for randomized controlled trials [RCTs] followed by other study designs. Main outcome measures were as follows: rates of clinical pregnancy, miscarriage and live birth as well as endocrine outcomes. Eighty-two abstracts were screened and six original articles were included. A RCT demonstrated that post-operative letrozole treatment did not improve spontaneous pregnancy rate. Another RCT reported no superiority of letrozole superovulation over clomiphene citrate [each combined with intrauterine insemination] in minimal-mild endometriosis and previous laparoscopic treatment. Anastrozole significantly inhibited the growth of endometriotic cells and their estrogen production in culture. In assisted reproductive technology [ART] cycles, dual suppression [Agonist/anastrozole] was tested in a pilot study with a pregnancy rate of 45% however, high pregnancy loss [30%] occurred. A retrospective study showed that letrozole may improve endometrial receptivity in endometriotic patients undergoing in vitro fertilization [IVF]. An opposite view from an in vitro study showed lower estradiol production and aromatase expression in cultured granulosa cells from endometriotic women undergoing IVF and marked reduction under letrozole. In conclusion, current evidence is limited. More trials are warranted to enhance our knowledge and provide a clear and unequivocal evidence to guide our clinical management of infertile women with endometriosis using AIs
ABSTRACT
OBJECTIVE: To compare the efficacy of the levonorgestrel-releasing intrauterine system (LNG-IUS) and oral norethisterone acetate (NET) for treatment of non-atypical endometrial hyperplasia in perimenopausal women. METHODS: One hundred and twenty perimenopausal women with non-atypical endometrial hyperplasia were selected in this randomized controlled trial. Patients received LNG-IUS (n=59) or NET (n=61; 15 mg/day for 3 weeks/cycle) for 3-6 months. Outpatient follow-up with endometrial biopsies were undertaken at 3, 6, and 12 months intervals after treatment. Outcome measures were; the regression rate, the time to regression and hysterectomy rate. RESULTS: A significantly higher regression rate was noted in the LNG-IUS group than in NET group at the 3rd, 6th and 12th month follow-up visits using intention-to-treat analysis (67.8% vs. 47.5%, relative risk [RR], 1.42; 79.7% vs. 60.7%, RR, 1.31; and 88.1% vs. 55.7%, RR, 1.58, respectively). However, no significant difference was found regarding the median time to regression (3 months). The hysterectomy rate during the follow-up period was significantly higher in the NET group (57.4% vs.22%, p<0.001). CONCLUSION: LNG-IUS treatment of non-atypical endometrial hyperplasia in perimenopausal women is more effective than NET for achieving disease regression for the majority within 1 year. Moreover, it can reduce the number of hysterectomies performed.