So, should you?

Jennifer Aniston and a host of other celebrities have done it. Should you?

At my book club recently we had a lively debate about baby names because one of the women in the group was about to have her first baby. Everyone joined in with their favourites, including one of the women who excitedly told the group she knows exactly what all three of her babies will be called.

I was a little taken aback by her conviction for one simple reason: this woman is fast approaching 40 and doesn’t have a boyfriend, let alone a life partner with whom she wants to have a baby.

She is, of course, like so many women you and I know, very attractive, incredibly successful and thoroughly independent. Like most privileged women of our generation, she was encouraged by her parents to get an education, to travel and to pursue a career. She’s done all of those things.

What our parents didn’t encourage us to do was pursue a man, a life partner. That, our parents and we assumed, would simply fall into place sometime along the way, and children would come soon after – the life puzzle complete.
Yet my friend’s life, like so many of our generation, has that last piece of puzzle missing. It is – it may not be politic to mention – a really dark blank for so many women. You can meet a man at any age but once you get to 40-plus you are at great risk of being too old to have your own biological child.

But now there is some real hope that, by freezing a cycle of eggs (cryopreservation), a woman can have a baby later in life, allowing her to extend her fertility until Mr Right walks into view or, in the case of a woman who has the man and the career, until she feels the time is right to have a baby. When she finds a partner or is in a position to take a career break, she can have her eggs thawed and use routine IVF procedures to get pregnant.

What makes egg freezing so exciting is it doesn’t pose the same moral and ethical dilemmas that embryo freezing does. While some couples have no problem with the concept of embryo freezing, others find it ethically confusing. For those who believe life begins at the moment of conception, each frozen embryo represents a life, and if unused, a life left unfulfilled. Egg freezing, like sperm freezing, presents us with the opportunity to extend ones fertility without these issues. If the eggs are not used, they are simply destroyed, or donated.

The main way in which age affects fertility is its impact on the quality of a woman’s eggs. A woman is born with her lifetime’s supply of eggs. Each month, when her period starts, she sheds one or so of those eggs. As time passes, age takes its toll on the remaining eggs and their quality deteriorates, making them less likely to be fertilised by a sperm to create a healthy baby. This is also why the risk of a baby being born with a chromosomal defect rises with age.

Before the age of 35, the odds of a woman falling pregnant naturally each cycle is around 25 per cent if she has intercourse at the right time and her partner has healthy sperm. When she reaches 35, that figure begins to drop off so that by the time a woman is 40, the chance of her falling
pregnant with each cycle drops to 10 per cent and, by the time she hits 45, that percentage is close to zero.

Of course, these percentages are only statistics; we all know women who have fallen pregnant naturally during their 40s. Lifestyle also influences fertility. A woman who has looked after herself physically is far more likely to have a baby at a later age than someone who has neglected or abused her health. Book club didn’t feel the right time to do it, but I really wanted to suggest to my friend that she considers freezing her eggs. Of course, such a procedure can seem drastic (as well as expensive), something for the Jennifer Anistons of the world. It is fraught with fear, confusion and misinformation.

What do the experts say?

So we asked Professor Thinus Kruger, head of the Fertility Clinic at Tygerberg Hospital and the Institute for Reproductive Medicine at Life Healthcare’s Vincent Pallotti hospital in Cape Town, to answer some of the most pertinent questions.

Do you think women should freeze their eggs to prolong their fertility?
Yes I do. I would not be against it if someone aged between 25 and 35 wanted to freeze her eggs. I would definitely advise it, ideally before the age of 35. Freeze your eggs and get that burden off your shoulders.

What does the procedure entail?
During the first consultation, the procedure is explained and discussed. A blood sample is taken so the patient can be screened [for HIV and hepatitis B and C]. Then the patient returns at the correct time in her cycle to receive hormones to stimulate her ovaries to produce more eggs than usual. This is known as superovulation. About three weeks later, the patient returns for harvesting. The patient is lightly sedated and the eggs retrieved trans-vaginally using a hollow needle that is guided using ultrasound. [The eggs – as many as 10 to 15 – are then frozen in liquid nitrogen].

How much does the procedure cost?
It costs around R12000 to R15000, depending on the clinic.

What are the success rates?
It’s so new but, based on international literature, I think you can say a fair rate is about 20 per cent per cycle. If you attempt three thawing cycles, that’s a cumulative rate of 60 per cent. We’ve successfully frozen eggs, we’ve thawed them and we’ve fertilised the eggs – we have one in culture this week – but we have not yet had our first baby from a frozen egg. It is such a new procedure but I know technically that it is working.

Are there any risks?
The risks to the woman are minimal.
Superovulation can trigger ovarian hyperstimulation syndrome, but you don’t get it when you don’t transfer embryos, so that risk is small. There is a theoretical risk of infection in the ovary but I have never seen it. Also, the ovary can swell, causing pain and discomfort, but very few people
complain about that.

For how long can eggs be frozen?
Usually 10 years.

Reproductive revolution

• false sense of security?
  Egg freezing is a comparatively new technology that has not yet been fully developed and tested. Some fertility experts believe that at this stage its use should be restriced to women with a clear medical need; for example, women about to have cancer treatment that will destroy their ovaries.

Others say that egg freezing offers women in their 30s who have to delay childbearing their best chances of success and that it should be made widely available. “There are no guarantees. But a woman is more likely to get pregnant at 40 with one of her eggs frozen in her early 30s than with her 40-year-old eggs,” says Dr Gillian Lockwood, medical director of the Midland Fertility Services in the UK.

Others argue that egg freezing may give people a false sense of security, discouraging women to have babies in their more fertile years, only to be disappointed when a frozen egg does not become a viable pregnancy.

• freezing techniques
  The first live human births from previously frozen eggs occurred during the late 1980s. High failure rates kept egg freezing on the sidelines for a decade.
  However, those fears were reduced in the 1990s when studies by Dr Debra Gook at the Royal Women’s Hospital in Melbourne showed that the internal structure of the egg and the chromosomes looked normal in eggs that survived slow freezing – then the prevailing technique. Unfortunately, relatively few eggs survived freezing.
  
  “These are the biggest cells in the body. They contain huge amounts of water that form massive ice crystals. These are what burst the cells,” says Dr Gook.
  
  However, recent changes to the slow-freezing method, such as altering the composition of the fluid the egg is suspended in before freezing, have meant that several teams around the world are now reporting thaw-survival rates approaching 80 per cent and fertilisation rates close to fresh eggs
  .
  Even so, for reasons not yet understood, more embryos are lost before implantation than with conventional IVF. Better survival rates – and fewer losses at implantation – are being reported with a newer technique called vitrification, in which eggs are frozen so quickly that ice crystals cannot form.

• pregnancy success
  There are estimated to have been fewer than 600 live births worldwide from previously frozen eggs – and even this is a hotly debated figure. Some studies put it as low as 300. To attempt to assess the live birth rate success, a team led by Dr Kutluk Oktay of the Center for Reproductive Medicine and Infertility in New York contacted every centre in the world that reported results of egg freezing between January 1997 and June 2005.
  
  The team found that the overall live birth rate for each embryo successfully created using a thawed egg and placed in a woman’s uterus was 22 per cent, with a marked rise to 32 per cent between 2002 and 2004. A second analysis, taking data from live births when only the vitrification technique was used, showed more promising results.

• baby birth defects
  Dr Andrea Borini of the Centre for Reproductive Health in Bologna reported that of 123 live births from his clinic’s cryopreservation programme, just two had major abnormalities: one had a nasal blockage; the other a rare developmental disorder. Both children had fathers with fertility problems. Other scientists suggest that there will need to be 100,000 live births from previously frozen eggs before safety can really be assessed.

• egg versus embryo
  Sperm cells are about 180th the size of a mature egg and thus can be easily preserved. Embryos, which are eggs that have been fertilised, are approximately the same size as mature eggs but are much more likely to survive the freezing/thawing cycles. This is due to the fact that the eggs’ membranes undergo dramatic changes during fertilisation, making them more likely to tolerate the stresses associated with freezing.