Comparative Evaluation of Early Pregnancy Outcomes Following Ovulation Induction with Letrozole Versus Clomiphene Citrate: Evidence from a Prospective Iraqi Cohort Study
DOI:
https://doi.org/10.22317/jcms.v11i5.1834Abstract
Objectives: To compare early pregnancy outcomes, including miscarriage, ectopic pregnancy, multiple pregnancy, and congenital anomalies, among women who conceived following ovulation induction with letrozole or clomiphene citrate.
Methods: A prospective comparative observational study was conducted at Al-Elwiya Maternity Teaching Hospital and a private clinic in Baghdad, Iraq, from March 2023 to December 2024. One hundred infertile women aged 21–35 years who conceived after ovulation induction with either letrozole (5 mg/day) or clomiphene citrate (100 mg/day) for five days (cycle days 3–7) were enrolled. Participants were followed through early pregnancy with serial sonography at 6, 8–11, and 18–20 weeks of gestation. Data were analyzed using SPSS version 23, and a p-value <0.05 was considered statistically significant.
Results: Adverse pregnancy outcomes occurred in 19.0% of women in the clomiphene group and 8.6% in the letrozole group, a difference that was not statistically significant (χ²(1)=2.342, p=0.126). Normal singleton pregnancies were more frequent with letrozole (91.4%) than with clomiphene (81.0%). The odds ratio for adverse outcomes in the clomiphene group was 2.49 (95% CI: 0.75–8.26). Twin pregnancies were observed only in the clomiphene group (7.1%). Congenital anomalies were rare and comparable between groups.
Conclusion: Although not statistically significant, letrozole was associated with fewer early pregnancy complications and a trend toward safer outcomes compared with clomiphene citrate. Both agents remain effective for ovulation induction, but letrozole may offer a more favorable safety profile for women at risk of early pregnancy loss.
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