BACKGROUND: Clomiphene citrate is used as the first line drug for anovulatory infertility treatment. When a woman fails to ovulate using clomiphene at maximum dose, letrozole is used as a second line drug.

OBJECTIVE: To determine association between a patient's age and body mass index (BMI) and their response to clomiphene citrate or letrozole in the treatment of anovulation-related infertility.

MATERIALS AND METHODS: The authors reviewed 147 patient records from January 2011 to August 2016 and investigated the age, BMI and response of patients when given clomiphene or letrozole for ovulation induction.

RESULTS: Ninety-nine (99) patients received clomiphene citrate while the other 118 patients received letrozole. Those who responded positively to clomiphene were at least 35 years old (72.2%) or had above normal BMI (61.5%). Patients who responded positively to letrozole were at least 35 years old (95%) and were categorized with above normal BMI (82.9%). The authors found that patients who are older than 35 years of age are more likely to respond to letrozole compared to younger patients.

CONCLUSION: This study found no significant association between BMI and response to either Letrozole or Clomiphene. Patients who are more than 35 years old are more likely to respond to letrozole, compared to younger patients.