Your Biological Clock: Freezing Your Eggs

By Alan Copperman, M.D.


You’re in your mid-thirties. You don’t have a boyfriend. But yes, you want children. Hear that clock ticking in the background?

Yes, the female biological clock is real.

In fact,  there are three key facts to consider regarding a female’s reproductive lifetime:

  1. Eggs are in limited supply. While men continue to make sperm throughout their lifetime, women are born with all the eggs they will ever have.  In fact, over 60% of eggs are lost before birth; over 80% are gone by the time a female reaches puberty.
  2. Egg quality diminishes as women age.  Female fertility peaks in the early 20s, and begins to decline thereafter.  The decline in quality becomes more pronounced around age 35, then declines at a faster rate beginning around 38 years of age.
  3. There is no way to stop nature, but there are some new options.  Physicians have been working for decades to help boost the fertility potential of infertile individuals and couples actively seeking to conceive. There was limited focus on, and success with, fertility preservation.  However, due to advancements in laboratory techniques and freezing protocols, physicians and laboratories have begun offering egg freezing for fertility preservation.  While a physician is not able to tell the health of an individual’s eggs, they can use some tests to predict whether she might be a candidate for egg freezing.

Oocyte cryopreservation, also known as egg freezing, is a new and exciting experimental procedure that may help a woman preserve her reproductive potential. This is a highly specialized procedure that is preformed by a reproductive endocrinologist, a physician who trains in obstetrics and gynecology and then receives additional training. At Reproductive Medicine Associates of New York, we work with Extend Fertility ™ to provide the egg freezing procedure.

Women who may benefit from egg freezing include:

1) Those women who are at risk of becoming sterile due to chemotherapy, radiotherapy or removal of their ovaries;

2) Women who are choosing to delay reproduction, for personal or career reasons, while attempting to maintain their reproductive potential;

3) Women who have a family history of endometriosis, early menopause or premature ovarian failure.

Oocyte cryopreservation involves the extraction of a woman’s unfertilized eggs from her uterus.  The process is similar to the beginning stages of an in vitro fertilization (IVF) cycle:

Stage 1: Ovarian stimulation and monitoring, The patient takes injectable hormones to increase oocyte production in order to obtain a number of eggs during the retrieval phase. The patient is closely monitored at the reproductive endocinologist’s office during this time and may have brief office visit every day or every other day for a total of 5-6 monitoring visits. When the physician determines a number of eggs are mature, he or she will schedule the next step.

Stage 2: Oocyte (egg) retrieval. Under sedation, the reproductive endocrinologist extracts mature eggs via ultrasound guidance. Egg retrieval is a minimally invasive procedure that normally takes less than 15 minutes. Patients require a recovery period of 1-2 hours at the surgical suite and should have a ride home, due to anesthesia. Patients typically can resume normal activity within the next day.

Stage 3:  Oocyte freezing. The retrieved oocytes are handled by specially trained laboratory technicians who will classify each egg and begin the freezing process.  The eggs are cooled and then are stored at extremely low temperatures.  At these temperatures, no cellular activity takes place, and, therefore can theoretically be stored almost indefinitely. Once frozen, the eggs may be transported to a long-term storage facility.

When the woman becomes ready to attempt pregnancy, the eggs can be transferred to a fertility specialist team who will thaw the stored oocytes, attempt to fertilize the eggs and transfer subsequent embryos.

Success Rates of Egg Freezing

Approximately 1000 babies have been born using eggs that were previously frozen and there is no evidence of increased risk to mothers or children born from this procedure.

Prior to offering egg freezing to patients, RMA of New York tested the process and the freezing media provided through their partnership with Extend Fertility.  Results showed:

–       Over 86% of eggs survived the freezing and thawing process.  This is significant achievement as the egg is the largest cell in the body made up mainly of water, which makes it particularly sensitive to damage from freezing.

–       Over 90% of thawed eggs achieved fertilization with use of the technique intracytoplasmic sperm injection (ICSI).  ICSI is a technique that takes a single sperm and injects it directly into an egg.  Due to some hardening of the outer shell of the egg after the thawing process, ICSI is recommended in these cases.

–       92% of fertilized eggs (now embryos) survived to day three, which is when a transfer could take place.

Why Egg Freezing

Lucia Vazquez works in sales and marketing for a pioneering biomedical company.  She enjoys her current position because it enables her to learn about new advances in medicine, and then distribute products that utilize those advances to consumers who can benefit from them.  Lucia had the foresight to freeze her eggs while still in her early thirties because she was not ready for children and wanted to increase her options to have a biological child at some future point.  She froze her eggs with Reproductive Medicine Associates of New York, Extend Fertility’s partner center in NY.  She says, “Egg freezing was definitely a great choice allowing me to take better control of my fertility options.” 

About Extend Fertility

Extend Fertility is dedicated to enriching women’s lives through revolutionary egg freezing science that gives women the option to effectively slow down the biological clock. The company brings together industry-leading science, medical care and storage facilities. By combining these critical elements with our outstanding educational resources and client services, Extend Fertility offers women the leading egg freezing experience available today.

For more information, visit

Alan Copperman, MD. is Director of the Division of Reproductive Endocrinology and Vice-Chairman of the Department of Obstetrics, Gynecology, and Reproductive Science at Mount Sinai Medical Center and Co-medical director of Reproductive Medicine Associates of New York,  the reproductive endocrinology and infertility division of Mount Sinai Medical Center and has been caring for patients in the midtown Manhattan location since 2001, with additional locations in Westchester and Long Island.  RMA of New York is a full-service fertility center that focuses on fertility preservation and family building treatment options. RMA of New York consistently achieves high live birth rates, while maintaining low rates of triplet pregnancies.  Highly individualized patient care is offered through seven reproductive endocrinologists, a urologist, a complementary care team of a clinical psychologist and a licensed clinical social worker, and well-trained team of health care professionals.  For more information, please call 212.756.5777 or visit