Saving your fertility

When the time is not right to start a family, there are ways to preserve your fertility for when circumstances are more ideal.

In Singapore, many men and women are conscious of the risk of 不孕症 and the increase in abnormal babies and pregnancy complications after the maternal age of 35. However, many women are pushed into trying for conception at a later age due to work pressures, financial pressures or the lack of a suitable partner. Marrying earlier is difficult for many young couples and trying for a family becomes more challenging and difficult as time plods on. With later marriages and the corresponding dip in a woman's fertility, many couples are concerned that their dreams of a family may not be realised.

For women with a family history of premature menopause, saving one's fertility potential may be critical for her to have her own genetically similar children.

Egg freezing is also a useful adjunct for those undergoing IVF, as it allows couples - who for personal or religious reasons - choose not to place extra embryos in cold storage and feel more comfortable storing the extra eggs instead.

In other unhappy instances, when cancer strikes for either men or women, saving fertility for a later time when one is in a stable state is often seen as having a positive impact for prognosis. For the women, there is usually a small window of opportunity prior to chemotherapy to save her eggs and/or embryos for a chance at having a child in the future. (Similarly for the men, sperm freezing can easily be performed prior to chemotherapy.)

Social egg freezing is a promising option to preserve eggs before they are damaged or depleted.

From 2012, the American Society of Reproductive Medicine declared that egg freezing is no longer an experimental procedure. Improvements in freezing methods and culture media have given many labs an almost 100% freeze and post-thawing survival rate. Apart from the cost of storage, the current cost for egg freezing is identical to that of routine IVF.

In Singapore, egg freezing is only available in the context of those suffering from cancer and desiring to store their eggs before undergoing chemotherapy. Egg freezing is also an option for them post-chemotherapy if they are not able to consider a pregnancy at the time. (Sperm freezing has been in place for many years.)

The egg freezing process

Called oocyte cryopreservation, egg freezing allows women to freeze and store their eggs until the time that they wish to start or expand their families. The benefit of freezing your eggs while you are still young and at your reproductive peak is one of the best ways to ensure a chance for a future pregnancy. While the uterus can carry a pregnancy well into the 40s and 50s, your ovaries and oocytes (eggs) do not age as well. Freezing your eggs by vitrification means they can be stored and 'suspended in time', preserving their quality. It is recommend that 10 eggs be stored for each pregnancy attempt. Most women 35 years or younger can expect to harvest from 10 to as many as 20 eggs per cycle.

This is being recognised globally as a particularly good option for women who have not had the opportunity to be a mother for various reasons.

Preparing for egg retrieval

Before the eggs are retrieved for freezing, you will need to undergo the same hormone-injection process as for IVF. Just as with the initial stages of the IVF process, it takes approximately 12 to 14 days for eggs to reach retrieval stage.

  • The process begins with a baseline test done a day or two after the onset of menses. This typically includes an ultrasound and a blood test.

For those with irregular menses, a cycle of oral contraceptive pills may be used to regulate the menses before starting ovarian stimulation. For those with regular cycles, this may not be necessary.

  • After your hormones are successfully suppressed, a series of carefully measured fertility medications is given to start ovarian stimulation. These hormone injections are given daily over 10 to 12 days to stimulate the ovaries and ripen multiple eggs. To monitor the eggs, regular timed clinic visits involving ultrasounds and blood tests are done to look for mature eggs.
  • If the case is urgent, as in the case of cancer therapy, stimulation can begin using special protocols at different phases of the cycle. These cycles have been shown to potentially produce adequate good quality eggs or embryos for storage.
  • When tests indicate that the eggs are approaching maturity, a trigger to simulate the LH surge is given and the eggs are then removed via a needle placed through the posterior vaginal vault.
  • The removed eggs are immediately frozen.

When you are ready to become pregnant, the cryopreserved eggs are thawed and each one is then injected with a single sperm to achieve fertilisation before they are transferred to the uterus as embryos.

Success rates

Younger is better when it comes to storing eggs and sperms. It must be remembered that frozen eggs from a 40 year old have only a 10% chance of success. An IVF cycle at age 42 with frozen eggs retrieved at 38 years is more likely to succeed than a fresh cycle at 42 years. To be effective, therefore, egg freezing is best carried out from age 35 or younger.

The risk of egg freezing

With ovarian stimulation, the risks of hyperstimulation are always possible, but with newer methods, such as an agonist trigger, these are greatly reduced. The risk of storing abnormal eggs is always possible as it is impossible to test the egg prior to freezing.

(Sperm freezing, on the other hand, is easily done and each ejaculate can be stored in multiple straws and are capable of being used in more than a single cycle of IVF.)

Conclusions

Egg or sperm freezing is a process that can be of benefit as an insurance for a chance at parenthood. While it is not for everyone, it definitely gives women and men more options where there were none before. It is not meant to encourage delayed parenthood but as a protection against childlessness, because there is always hope as long as there are eggs or sperm in the bank.

Corporates for egg-freezing

As part of its package of employee medical benefits that includes free meals, four months of maternity leave and financial assistance for newborn expenses, Facebook recently began to offer female employees financial assistance of up to US$20,000 for egg-freezing. Apple will begin offering this benefit as well from 2015. Though well-intended, these announcements have generated varied responses, from appreciation to outrage that corporates are getting into such a personal aspect of an employee's life.

Dr Ann Tan
Dr Ann Tan, PBM
Obstetrician & Gynaecologist
MBBS (S'PORE), MRCOG (LONDON),
M MED (O&G) FAM (SINGAPORE)
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