Related Experiment Video
Updated: Apr 17, 2026

Fertility Preservation Through Oocyte Vitrification: Clinical and Laboratory Perspectives
Published on: September 16, 2021
Changing ovarian stimulation parameters in a subsequent cycle does not increase the number of euploid embryos
Brooke Hodes-Wertz1, David H McCulloh1, Alan S Berkeley1
1New York University Fertility Center, Langone Medical Center, New York University, New York, New York.
Objective:
To compare the euploidy outcome in patients that underwent 2 ovarian stimulation cycles with trophectoderm biopsy.
Design:
Retrospective repeated-measures cohort study.
Setting:
University-based fertility center.
Patient(S):
A total of 116 patients, from 2011 through 2013, that underwent 2 ovarian stimulation cycles followed by trophectoderm biopsy with array comparative genomic hybridization.
Intervention(S):
Days of stimulation, average diameter of the 2 lead follicles on day of trigger, dose of gonadotropins, type of cycle (gonadotropin-releasing hormone [GnRH] antagonist, GnRH-antagonist plus clomiphene citrate [CC], microdose GnRH agonist).
Main Outcome Measure(S):
Number of euploid embryos.
Result(S):
Patients were analyzed based on whether they had ≥1 euploid embryos in their first cycle vs. none. There was no increase in the number of euploid embryos with more days of stimulation or increases in the dose of gonadotropins in either group. Significantly more euploid embryos were seen in patients who had no euploid embryo(s) in the first cycle (Group 0) that had CC added to a GnRH-antagonist cycle (1.11 more euploid embryos) or were triggered when follicle sizes were 2 mm larger (0.40 euploid embryos), but these increases were not significant compared with a control group. Patients with euploid embryo(s) in the first cycle (Group 1) had significantly more euploid embryos when daily dose was increased by 75-149 international units, but this relationship was not significant compared with a control group with no increase in daily dose.
Conclusion(S):
No specific intervention increased the number of euploid embryos within the same patient any more than simply repeating a similar stimulation cycle. An attempt was made to control for interpatient variability, but individual patients have considerable intercycle variability.
Related Concept Videos
Hormonal Control of the Ovarian Cycle
Before puberty, the hypothalamus releases GnRH in a low frequency, low amplitude pulsatile manner. This along with the immature hypothalamic-pituitary-gonadal axis activity, results in low estrogen levels and the absence of a fully functional ovarian cycle. At puberty, GnRH secretion increases in both frequency and...
Ovarian Cycle
In Vitro Fertilization
The IVF process begins with ovarian stimulation, during which reproductive endocrinologists prescribe hormonal medications to stimulate the ovaries to produce multiple eggs instead of the single...
Hormonal Regulation of the Menstrual Cycle
At puberty, GnRH begins a pulsatile release pattern, which triggers the anterior pituitary gland to secrete follicle-stimulating hormone (FSH) and luteinizing hormone (LH). The frequency and amplitude of GnRH pulses vary across the menstrual cycle, with faster pulses favoring LH release and slower pulses favoring FSH...

