Citiraj:
Congenital malformations among 911 newborns conceived after infertility treatment with letrozole or clomiphene citrate.Tulandi T, Martin J, Al-Fadhli R, Kabli N, Forman R, Hitkari J, Librach C, Greenblatt E, Casper RF.
Department of Obstetrics and Gynecology, McGill University, Montreal, Quebec, Canada.
OBJECTIVE: To evaluate the incidence of congenital malformations among offspring of mothers who conceived with clomiphene citrate (CC) or with letrozole treatment for infertility. DESIGN: Retrospective study. SETTING: 5 fertility centers in Canada. PATIENTS: 911 newborns from women who conceived following CC or letrozole treatment. INTERVENTIONS: Examination of medical files of both mother and newborn, and cross-checked with the parents by telephone calls. MAIN OUTCOME MEASURES: Identified major and minor congenital malformations, birth weight, age of the mother, and type of treatment that led to the conception. RESULTS: Overall, congenital malformations and chromosomal abnormalities were found in 14 of 514 newborns in the letrozole group (2.4%) and in 19 of 397 newborns in the CC group (4.8%). The major malformation rate in the letrozole group was 1.2% (6/514) and in the CC group was 3.0% (12/397). One newborn in the letrozole group was found to have a ventricular septal defect (0.2%) compared to 4 newborns in the CC group (1.0%). In addition, the rate of all congenital cardiac anomalies was significantly higher (P: 0.02) in the CC group (1.8%) compared to the letrozole group (0.2%). CONCLUSION: There was no difference in the overall rates of major and minor congenital malformations among newborns from mothers who conceived after letrozole or CC treatments. However, it appears that congenital cardiac anomaly is less frequent in the letrozole group. The concern that letrozole use for ovulation induction could be teratogenic is unfounded based on our data.
PMID: 16650422 [PubMed - indexed for MEDLINE]
Citiraj:
1: Fertil Steril. 2006 Feb;85(2):277-84. Compound via MeSH, Substance via MeSH, Books, LinkOut
A new era in ovulation induction.
• Holzer H,
• Casper R,
• Tulandi T.
Department of Obstetrics and Gynecology, McGill University, Montreal, Quebec, Canada.
OBJECTIVE: To evaluate the efficacy of aromatase inhibitors in ovulation induction, superovulation, and IVF. DESIGN: A literature search was conducted with the key words "aromatase inhibitor," "letrozole," "anastrazole," "ovulation induction," "ovulation," and "superovulation" in MEDLINE, EMBASE, and the Cochrane Database of systematic reviews. RESULT(S): Ovulation induction with letrozole is associated with an ovulation rate of 70%-84% and a pregnancy rate of 20%-27% per cycle. In one study, ovulation and pregnancy rates with letrozole seemed to be higher than those of anastrazole. In superovulation, letrozole is associated with few developing follicles and thick endometrium. The use of letrozole for superovulation is associated with a pregnancy rate higher than with the use of clomiphene citrate (CC) (16.7% vs. 5.6%). The addition of letrozole to FSH treatment leads to a decreased FSH requirement. The pregnancy rate for treatment with letrozole and FSH was similar to that for FSH alone. CONCLUSION(S): Aromatase inhibitors are as effective as or superior to CC in ovulation induction and in superovulation. Unlike CC, they do not carry an antiestrogenic effect on the endometrium. Given the advantages of aromatase inhibitors, they can be used to replace CC as ovulation-inducing drugs. Their role in IVF remains to be determined.
PMID: 16595197 [PubMed - indexed for MEDLINE]