OBJECTIVE: To investigate whether conservative surgery on ovarian endometriomas 
before an IVF cycle improves fertility outcomes.
DESIGN: Retrospective, matched case-control study.
SETTING: Two academic IVF programs.
PATIENT(S): One hundred eighty-nine women with endometriomas who underwent IVF 
treatment: 56 women proceeded directly to IVF, and 133 first underwent 
conservative ovarian surgery.
INTERVENTION(S): Controlled ovarian hyperstimulation and IVF-ET.
MAIN OUTCOME MEASURE(S): Response to gonadotropins, fertilization, implantation, 
and pregnancy rates.
RESULT(S): Aside from lower peak E(2) levels on the day of hCG and a higher 
total FSH dose in women previously operated for an endometrioma, no significant 
differences were found between the two groups in the different IVF variables 
analyzed.
CONCLUSION(S): Laparoscopic cystectomy for endometriomas before commencing an 
IVF cycle does not improve fertility outcomes. Proceeding directly to controlled 
ovarian hyperstimulation in women with asymptomatic ovarian endometriomas might 
reduce the time to pregnancy, the costs of treatment, and the hypothetical 
complications of laparoscopic surgery. Conversely, conservative surgical 
treatment of ovarian endometriomas in symptomatic women does not impair IVF or 
intracytoplasmic sperm injection success rates.