Experts raise idea to let healthy women do so at the peak of their fertility
By Salma Khalik, The Straits Times, 16 Mar 2012
HEALTHY young women should be allowed to freeze their eggs for future use in a move that could help to reverse Singapore's falling birth rate, say several fertility experts.
When it comes to getting pregnant and delivering thriving babies, it is not the mother's age that matters but how old her eggs are. Freezing them while the woman is at the peak of her fertility can allow her to put off having children until later in life, perhaps when she has pursued a career or met the right man.
The technique is becoming increasingly popular in countries such as Canada, Australia and the Netherlands, where it is used to help those in their late 30s and 40s give birth to healthy infants.
As the science improves, it is becoming easier and the success rate is growing. The subject was raised at a three-day fertility workshop this month, where the experiences of other countries were shared.
In Singapore, only women who might lose their fertility through medical treatments such as chemotherapy are allowed to undergo the procedure.
By contrast, social egg freezing allows those with no medical conditions to do so while they are in their late 20s or early 30s, helping them to defer motherhood until later in life.
Several fertility experts said Singapore's law should be amended to allow this practice, given that many women here are waiting longer before getting married. They said it might even reverse the decline in the Republic's birth rate.
All stressed that the best way is for women to conceive naturally at a young age.
Dr Sheila Loh, clinical director of Raffles Fertility Centre, said: 'However, there should be opportunities for those who feel they may get married only later on and would like to 'preserve' their fertility.'
She said women here should have this option, given the excellent results from major centres in various places around the world such as the United States, Canada and Spain. 'This is especially so with our low fertility rate and the rise in age of marriage,' she added.
Dr Loh Seong Feei, medical director of the Thomson Fertility Centre, said: 'Later marriages and motherhood translate into more subfertility issues as female age increases.'
The growing number of Singaporean women getting married after the age of 30 caused fertility and birth rates to slump to their lowest level last year, he said.
Dr Suresh Nair, who has a clinic in Mount Elizabeth Medical Centre, also noted that the safety of this technology has been well established for more than 10 years.
It is common knowledge that the older a woman gets, the harder it becomes to conceive, and the higher the risk of a miscarriage or some kind of abnormality in the baby.
So those who are single but have every intention of getting married later might find this option appealing. It could also suit women who are pursuing a career and have pushed back starting a family.
However, there is some hassle involved as they are essentially going through a cycle of in-vitro fertilisation (IVF), where the egg is harvested, then fertilised outside the body and the resulting embryo implanted in the womb.
In this case, however, it is stored for future use.
The technique is also not cheap, with one cycle of egg collection costing anywhere between $5,000 and $15,000. Storing the eggs, on the other hand, is relatively cheap at $250 to $300 a year.
A Scottish study released two years ago found that women lose 88 per cent of their eggs by the time they are 30. When they reach 40, they have only 3 per cent left. A woman is born with a fixed pool of eggs. As the body picks the best at each menstrual cycle, those that are left tend to be of poorer quality.
But an older mother using an egg harvested earlier in life faces only the same risk as she did when the egg was frozen, said one of the speakers, Professor Tan Seang Lin, medical director of the Montreal Reproductive Centre.
The latest techniques show that thawed eggs have the same rate of fertilisation as those which are freshly harvested, he added. But because they are younger, they are less likely to have abnormalities that often lead to miscarriages in older women.
Genetic testing can cut the risk of miscarriage
By Salma Khalik, The Straits Times, 16 Mar 2012
THE eggs looked healthy enough, but Professor Tan Seang Lin needed to be sure.
He was helping a woman to conceive through invitro-fertilisation (IVF) at the Montreal Reproductive Centre, and wanted to check that there were no defects. Fortunately for the patient, Canada allows eggs to be tested genetically.
Prof Tan discovered that the two healthiest-looking ones had an extra chromosome each. This means the embryo would not have developed normally, leading to a miscarriage.
All but one of the five eggs were defective. The woman, who is in her 40s, used the one that worked to become pregnant.
Singapore does not allow genetic testing on eggs or embryos, unless there is a chance of hereditary diseases such as thalassemia. This is to avoid parents picking their child's sex or scientists using genetic manipulation to produce a 'super' baby.
However, Prof Tan said rules can be put in to allow genetic testing only for defects. This could benefit women undergoing IVF, where the egg is fertilised outside the body and the resulting embryo implanted in the womb. This is because it would reduce the chance of doctors implanting a defective embryo which is miscarried, or grows into a baby with congenital problems.
'You can't tell a bad egg by just looking at it,' said Prof Tan.
Dr Ng Soon Chye, a fertility expert in private practice, is all for genetic testing of embryos as it will 'increase the efficiency' of the IVF treatment.
'A 40-year-old has an 80 per cent risk of having problems with the embryo. That's why pregnancy rates are very low,' he said.
Making sure that there are no genetic defects could also make it easier to convince the woman to have only one embryo implanted, he added.
Older patients who have failed once to give birth through IVF often have up to three embryos placed in their wombs. Multiple births tend to come with problems, and can mean babies needing time in intensive care.
Dr Ng said laws can specify that only genetic defects are tested and not the gender of the baby. He said: 'That's all you really want to know - whether the embryo is good or not.'
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