Publications by authors named "N M H Bulow"
The role of letrozole in in vitro fertilization treatment: new remedy or old mirage?
Fertil Steril
January 2025
Article Synopsis
- - Aromatase inhibitors, especially letrozole (LZ), are now recognized as effective first-line treatments for inducing ovulation and enhancing intrauterine insemination outcomes.
- - LZ is gaining traction as an adjunct to gonadotropin therapy in IVF, particularly beneficial for women with estrogen-sensitive cancers, by lowering estrogen levels.
- - Recent studies suggest that LZ can aid poor responders in IVF, mitigate ovarian hyperstimulation syndrome, and improve the luteal phase, while also being useful for preparing the endometrium in frozen-thawed embryo transfers.
This review describes the current evidence regarding the putative indications of letrozole (LTZ) in fertility treatment. Prior to intrauterine insemination, LTZ is recommended in women with normogonadotrophic oligo-anovulation. In ovulatory women, LTZ is equal to clomiphene and may be used instead of exogenous gonadotrophin.
View Article and Find Full Text PDFImpact of letrozole co-treatment during ovarian stimulation on oocyte yield, embryo development, and live birth rate in women with normal ovarian reserve: secondary outcomes from the RIOT trial.
Hum Reprod
November 2023
Study Question: Does letrozole (LZ) co-treatment during ovarian stimulation with gonadotropins for in IVF impact follicle recruitment, oocyte number and quality, embryo quality, or live birth rate (LBR)?
Summary Answer: No impact of LZ was found in follicle recruitment, number of oocytes, quality of embryos, or LBR.
What Is Known Already: Multi-follicle stimulation for IVF produces supra-physiological oestradiol levels. LZ is an aromatase inhibitor that lowers serum oestradiol thus reducing negative feedback and increasing the endogenous gonadotropins in both the follicular and the luteal phases, effectively normalizing the endocrine milieu during IVF treatment.
Context: Supraphysiological sex steroid levels at the follicular-luteal phase transition are implicated as the primary cause of luteal insufficiency after ovarian stimulation (OS) for in vitro fertilization.
Objective: We aimed to determine the impact of suppressing estradiol levels during OS of multiple dominant follicles on the unsupported luteal phase and markers of endometrial maturation.
Methods: At 2 university hospitals, 25 eligible egg donors were randomized to undergo OS using exogenous gonadotropins with or without adjuvant letrozole 5 mg/day.