Oocyte Cryopreservation: Slow Cooling Versus Vitrification Techniques on Oocyte Survival

Infertility Clinical Trial

Official title:

Oocyte Cryopreservation: Comparison of Slow Cooling Versus Vitrification Techniques on Oocyte Survival, Fertilization, and Embryo Development

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00602966
• Other study ID #: 06-336-2
• Secondary ID: 26525
• Status: Completed
• Phase: N/A
• First received: January 15, 2008
• Last updated: October 26, 2011
• Start date: July 2006
• Est. completion date: May 2010

Study information

• Verified date: October 2011
• Source: University of Connecticut Health Center
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Institutional Review Board
• Study type: Observational

Clinical Trial Summary

Oocyte cryopreservation has been studied for many years without much success in refining a method that has consistent, reliable results in producing viable embryos and clinical pregnancies. In 1986 the first baby was born from an embryo created from a frozen oocyte; however, since then there have been less than 150 births from frozen eggs. To date, there are no reportable adverse outcomes in the children born from frozen oocytes. The research continues to look at different methods of oocyte cryopreservation. Many smaller studies have been conducted with some success but larger clinical trials are needed to replicate these findings. The conventional cryopreservation technique has been slow cooling with differing methods of freezing; however, vitrification is now being researched as the potential cryopreserving method that holds some promise for the future.

Our hypothesis is the use of vitrification (quick freezing) to cryopreserve oocytes in patients undergoing in-vitro fertilization will be more successful than slow freezing in oocyte survival, fertilization rate with ICSI and subsequent embryo development, implantation rate and pregnancy rate.

Description:

Cryopreservation of oocytes is desirable because it: 1) would allow infertility patients to store excess oocytes instead of embryos, eliminating some of the ethical and religious concerns that accompany embryo storage; 2) permit storage of donor oocytes to avoid donor-recipient synchronization difficulties; and 3) can help women who may face sterilization due to chemotherapy or radiation. Oocyte cryopreservation is therefore gaining in popularity as an option for infertility treatment as well as fertility preservation.

Oocyte cryopreservation using conventional slow-cooling methods has not had much success; however more recent results have provided more optimism (Boldt et al., 2003; Porcu et al., 1997; 2000; 2002; Yang et al., 1998; 1999; 2002; Winslow et al., 2001). Vitrification has also been employed (Hong et al., 1999; Kuleshova et al., 1999; Yoon et al., 2000, 2003; Chung et al 2000; Wu et al., 2001: Kuwayama et al., 2005) with increased oocyte survival rate and live births. Vitrification is performed by suspending the oocytes in a solution containing a high concentration of cryoprotectants and then plunging them directly into liquid nitrogen (Rall and Fahy, 1985). The advantage of this technique is to prevent the formation of ice crystals within the oocyte. However the toxic effect of the high concentration of the cryoprotectant media has been a concern. New vitrification techniques which attempt to accelerate the cooling rate by decreasing the cryosolution volume and concentration, may reduce the potential toxicity. In addition, a more rapid cooling rate results in reduced chilling injury (Vajta et al., 1998).

Recruitment information / eligibility

• Status: Completed
• Enrollment: 14
• Est. completion date: May 2010
• Est. primary completion date: October 2009
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Female
• Age group: 21 Years to 36 Years

Eligibility

Inclusion Criteria:

• Patients = 36 years old

• Day #3 follicle stimulation hormone (FSH) < 10mIU/ml, and Estradiol < 70 pg/ml.

• The study will be limited to couples who do not wish to cryopreserve excess embryos, who would otherwise have their excess oocytes discarded.

• Body Mass Index (BMI) = 35

• Patients currently being seen in our offices

Exclusion Criteria:

• Male partner requiring microsurgical epididymal sperm aspiration or testicular sperm extraction (MESA/TESE) for sperm retrieval

• Day #3 follicle stimulation hormone (FSH) > 10mIU/ml, or estradiol > 70 pg/ml

• Diagnosis of Polycystic Ovary Syndrome (PCOS)

• Body Mass Index (BMI) >35

Study Design

Observational Model: Case Control, Time Perspective: Prospective

Related Conditions & MeSH terms

• Infertility

Locations

Country	Name	City	State
United States	The Center for Advanced Reproductive Services	Farmington	Connecticut

Sponsors (2)

Lead Sponsor	Collaborator
University of Connecticut Health Center	EMD Serono

Country where clinical trial is conducted

United States, 

References & Publications (11)

Boldt J, Cline D, McLaughlin D. Human oocyte cryopreservation as an adjunct to IVF-embryo transfer cycles. Hum Reprod. 2003 Jun;18(6):1250-5. Erratum in: Hum Reprod. 2004 Aug;19(8):1929. — View Citation

Carroll J, Depypere H, Matthews CD. Freeze-thaw-induced changes of the zona pellucida explains decreased rates of fertilization in frozen-thawed mouse oocytes. J Reprod Fertil. 1990 Nov;90(2):547-53. — View Citation

Fuku E, Xia L, Downey BR. Ultrastructural changes in bovine oocytes cryopreserved by vitrification. Cryobiology. 1995 Apr;32(2):139-56. — View Citation

Hong SW, Chung HM, Lim JM, Ko JJ, Yoon TK, Yee B, Cha KY. Improved human oocyte development after vitrification: a comparison of thawing methods. Fertil Steril. 1999 Jul;72(1):142-6. — View Citation

Kuleshova L, Gianaroli L, Magli C, Ferraretti A, Trounson A. Birth following vitrification of a small number of human oocytes: case report. Hum Reprod. 1999 Dec;14(12):3077-9. — View Citation

Porcu E, Fabbri R, Damiano G, Giunchi S, Fratto R, Ciotti PM, Venturoli S, Flamigni C. Clinical experience and applications of oocyte cryopreservation. Mol Cell Endocrinol. 2000 Nov 27;169(1-2):33-7. Review. — View Citation

Porcu E, Fabbri R, Seracchioli R, Ciotti PM, Magrini O, Flamigni C. Birth of a healthy female after intracytoplasmic sperm injection of cryopreserved human oocytes. Fertil Steril. 1997 Oct;68(4):724-6. — View Citation

Rall WF, Fahy GM. Ice-free cryopreservation of mouse embryos at -196 degrees C by vitrification. Nature. 1985 Feb 14-20;313(6003):573-5. — View Citation

Stachecki JJ, Cohen J, Schimmel T, Willadsen SM. Fetal development of mouse oocytes and zygotes cryopreserved in a nonconventional freezing medium. Cryobiology. 2002 Feb;44(1):5-13. — View Citation

Stachecki JJ, Cohen J, Willadsen S. Detrimental effects of sodium during mouse oocyte cryopreservation. Biol Reprod. 1998 Aug;59(2):395-400. — View Citation

Stachecki JJ, Cohen J, Willadsen SM. Cryopreservation of unfertilized mouse oocytes: the effect of replacing sodium with choline in the freezing medium. Cryobiology. 1998 Dec;37(4):346-54. — View Citation

* Note: There are 11 references in all — Click here to view all references

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Oocyte survival		When patient returns for thaw cycle	No
Secondary	Implantation rate		2 weeks after transfer of thawed oocyte	No