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A Comparison of Two Freezing Techniques

A Comparison of Two Freezing Techniques

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT00852306
Enrollment
18
Registered
2009-02-26
Start date
2009-02-28
Completion date
2012-10-31
Last updated
2012-10-10

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Infertility

Keywords

oocyte freezing, vitrification, slow freeze, fertility preservation

Brief summary

The purpose of this study is to determine the best way to freeze eggs in order to preserve the fertility potential of young women.

Detailed description

Human egg freezing is rapidly becoming a vital tool in Assisted Reproductive Technology. Candidates for egg freezing include women without partners who wish to preserve their fertility; cancer patients at risk of losing fertility from chemotherapy; and donor egg recipients. While in the past, egg freezing has not been as successful as embryo freezing in producing live births, recent experience in several centers has demonstrated significant improvement, with pregnancy rates comparable to those achieved with frozen embryos. The purpose of this study is to determine the best method to freeze eggs. We shall be seeking volunteers from the egg donor program, since young, fertile donors represent the best model to study the effect of egg freezing. We plan to enroll 12 recipients and 6 donors in this study. Each egg donor will go through a stringent screening process (medical, genetic and psychological). Eggs retrieved from all donors will be split in half: one half will be frozen by the slow freeze method, and the other half by vitrification. Each of the six donors will be paired with two recipients; each recipient will be assigned half the total eggs frozen. For each recipient, half of the eggs will come from the slow freeze group and the other half will come from vitrification. When the recipient's uterine lining is deemed ready (following estrogen treatment and ultrasound monitoring), thawing will be performed on eggs frozen by either the slow freeze or the vitrification method. The thaw process will be randomized between the two types of freezing. One sperm will be injected into each egg that survived the freeze. Fertilization and embryo development will be recorded. Ideally, two embryos will be transferred into the recipient's uterus. Pregnancy will be determined by a blood test and followed by serial blood tests and ultrasound. The study will determine which freezing method yields better survival and pregnancy rates.

Interventions

PROCEDUREoocyte freezing

retrieved oocytes from the donor will be split in half and frozen by both existing egg freezing methods: slow freezing and vitrification. The recipients will then be randomized as to which group of eggs will be thawed out for their first attempt at achieving a pregnancy.

Sponsors

EMD Serono
CollaboratorINDUSTRY
Northwell Health
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
SUPPORTIVE_CARE
Masking
NONE

Eligibility

Sex/Gender
FEMALE
Age
21 Years to 50 Years
Healthy volunteers
Yes

Inclusion criteria

* donors: women ages 21-32 who wish to donate their eggs; must pass medical, physical and psychological screening. * recipients: women under the age of 50 who wish to have eggs donated to them through the Donor Egg Program and who aslo pass the medical, physical and psychological screening.

Exclusion criteria

* donors: those who do not pass the genetic screening or psychological testing, as described below * recipients: those who do not pass the screening. The genetic screening of donors will involve the following: * All donors will be screened for Cystic Fibrosis, Fragile X and Spinomuscular Atrophy (SMA). * In addition, donors of Ashkenazi Jewish origin will be screened for Gaucher's disease, Canavan,Tay -Sachs, Familial Dysautonomia, Niemann Pick, Fanconi's Anemia, Bloom and Mucolipidosis Type IV. * Donors of African-American origin will be screened for Sickle-Cell disease. * Donors of Asian, Mediterranean, Latino or Hispanic origins will be screened for Thalassemia. Recipient Screening: A Reproductive Endocrinologist (RE) at the Center will take a detailed history and perform a physical examination on all potential recipients. The RE will assess the health of the potential recipient in order to assess her capacity to carry a pregnancy. Previous IVF cycles, successful or unsuccessful, will have no implication on recipient selection. The recipient and her partner (if applicable) will meet with the program psychologist. The psychological evaluation is detailed below. Psychological evaluation: A psychological evaluation will be conducted of the Recipient, her partner (if applicable) and the Donor. The purpose of these evaluations is to determine the suitability of the parties to participate in the Donor Egg Program. Psychological tests will be administered by the Center as part of the evaluation process. These evaluations may result in a recommendation that one and/or all of the parties not participate in the Donor Egg Program. The psychologist will not be providing any advice or treatment to the Donor or Recipient(s). Nor will the Donor or Recipient(s) be entitled to the results of the Psychologist's evaluation. The Psychologist will provide the results of his/her evaluations to the Center for Human Reproduction. As with our standard Donor Egg Program practices, there will be an upper age limit of 50 years for all recipients participating in the study.

Design outcomes

Primary

MeasureTime frame
Achievement of a pregnancy, as determined by a fetal heartbeat2 months

Secondary

MeasureTime frame
Incidence rate of embryo formation (percentage of embryos formed/number of eggs fertilized)2 days
Percentage of eggs that result in blastocyst formation1 week
Oocyte survival (the percentage of eggs that survive the freeze-thaw procedure)2 days
ICSI fertilization rate (percentage of eggs that fertilize)2 days

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026