Hum. Reprod. Advance Access originally published online on April 22, 2004
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Human Reproduction, Vol. 19, No. 6, 1457-1460,
June 2004
© 2004 European Society of Human Reproduction and Embryology
Embryo quality in natural versus stimulated IVF cycles
The Fertility Clinic, Rigshospitalet, University Hospital of Copenhagen Section 4071, Blegdamsvej 9, DK-2100, Copenhagen, Denmark
1 To whom correspondence should be addressed. e-mail: sziebe{at}rh.dk
BACKGROUND: The impact of controlled ovarian stimulation (COS) on oocyte and subsequent embryo quality remains controversial. In the present study we have compared embryo quality in natural and stimulated cycles in the same group of patients. METHODS: This retrospective study was comprised of patients with a regular menstrual cycle who had IVF after COS using rFSH in a long GnRH agonist protocol. In all stimulated cycles the patients had fresh embryos transferred and surplus good quality embryos cryopreserved. Subsequently the same patients were treated with a modified FER cycle (mFER) where thawing of the frozen embryos was combined with aspiration of the dominant follicle in the natural cycle. The embryo cleavage stage and quality score were compared between the stimulated and the natural cycle for the patients having an embryo in the natural cycle. RESULTS: In 177 cases patients returned for mFER in a natural cycle. Spontaneous ovulation had occurred in 35 cycles. In 17 cycles no oocyte was retrieved at aspiration and in 125 cycles 128 oocytes were aspirated. In the stimulated cycles from these patients we had obtained 950 embryos (cleavage rate 70.4%) versus 85 embryos (cleavage rate 66.4%) (P = 0.34) in the natural cycles. Comparing the embryos in the natural and stimulated cycles in all patients having an embryo in the natural cycle, we found no difference in the distribution between the different cleavage stages. Of the cleaved embryos, 53% in the stimulated cycles had 
4 cells versus 59% in the natural cycles after 2 days culture (P = 0.31). In the stimulated cycles 61% of the embryos had <10% fragmentation at the time of transfer on day 2, compared to 69% in the natural cycles (P = 0.15). CONCLUSION: The administration of exogenous gonadotrophins was not reflected in cleavage capacity or quality assessment of the resulting embryos.
Key words: developmental potential/embryo quality/impact of gonadotrophins/in vitro/in vivo
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  C. Hayden GnRH analogues: applications in assisted reproductive techniques Eur. J. Endocrinol., December 1, 2008; 159(suppl_1): S17 - S25. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. M. Nelson, R. W. Yates, and R. Fleming Serum anti-Mullerian hormone and FSH: prediction of live birth and extremes of response in stimulated cycles implications for individualization of therapy Hum. Reprod., September 1, 2007; 22(9): 2414 - 2421. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 N. S. Macklon, R. L. Stouffer, L. C. Giudice, and B. C. J. M. Fauser The Science behind 25 Years of Ovarian Stimulation for in Vitro Fertilization Endocr. Rev., April 1, 2006; 27(2): 170 - 207. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. M.R. Gerris Single embryo transfer and IVF/ICSI outcome: a balanced appraisal Hum. Reprod. Update, March 1, 2005; 11(2): 105 - 121. [Abstract] [Full Text] [PDF]
|
|