PMID16478764
:
Efficacy of combined metformin-letrozole in comparison with metformin-clomiphene citrate in clomiphene-resistant infertile women with polycystic ovarian disease.
Abstract
BACKGROUND
Adding metformin to clomiphene citrate in clomiphene-resistant polycystic ovary syndrome (PCOS) patients increases ovulatory response. However, because of anti-estrogenic effects of clomiphene it may be associated with lower pregnancy rate, offsetting the ovulation rate benefit. Letrozole is an aromatase inhibitor which induces ovulation without anti-estrogenic effects.
METHODS
Infertile women with PCOS were randomly divided into metformin-letrozole (29 patients) and metformin-clomiphene groups (30 patients). After an initial 6-8 weeks of metformin, they received either letrozole (2.5 mg) or clomiphene (100 mg) from day 3-7 of their menstrual cycle. Estradiol (E2) levels, number of follicles, pregnancy rates and endometrial thickness were measured on the day of HCG administration.
RESULTS
Mean total E2 and E2 per mature follicle were significantly higher in clomiphene group without a difference in mean number of mature follicles >18 mm and ovulation rate. Endometrial thickness was significantly higher in letrozole group. The pregnancy rate in letrozole group (10 patients, 34.50%) as compared with clomiphene group (5 patients, 16.67%) did not show significant difference, whereas full-term pregnancies were higher in letrozole group [10 patients (34.50%) versus 3 patients (10%)].
CONCLUSION
In clomiphene-resistant PCOS patients, the combination of letrozole and metformin leads to higher full-term pregnancies.
Structured Findings
letrozole (2.5 mg)
significantly decreased
Estradiol (E2) levels
compared to
clomiphene (100 mg)
letrozole (2.5 mg)
significantly increased
Endometrial thickness
compared to
clomiphene (100 mg)
Structured Markup
| Intervention |
Comparator |
Outcome |
Label |
| letrozole (2.5 mg) |
clomiphene (100 mg) |
Estradiol (E2) levels |
significantly decreased |
| letrozole (2.5 mg) |
clomiphene (100 mg) |
Endometrial thickness |
significantly increased |