With more and more women choosing to have children later in life, many are opting to freeze their eggs.
In 2017 alone, 1,463 egg-freezing cycles were carried out in the UK, up from just 234 in 2010, according to the Human Fertilisation and Embryology Authority (HFEA).
The procedure has come under fire today as experts criticise its “storage limit”. Under UK law, eggs can typically only be frozen for 10 years.
Critics argue there is no scientific evidence supporting this, the BBC reported. As a result, healthy eggs are being destroyed too soon, dashing a woman’s hopes of becoming a mother.
This Fertility Awareness Week, we look at what egg freezing is and how a woman can maximise her chances of success.
Why women freeze their eggs
A woman’s fertility naturally declines with age, with the number and quality of her eggs both dropping.
But this is not stopping the growing number of women choosing to become mothers later in life. In 2016, around 5% of all live births in England and Wales were in women aged 40-to-44, according to the Office of National Statistics.
Some delay having children simply because they have not met the right partner. Others may not be financially stable enough to raise a child or may prefer to progress further in their careers before becoming a mother.
Medical treatments, like chemo or radiotherapy, can also cause infertility, prompting many patients to freeze their eggs ahead of the intervention.
A transgender person who is transitioning may also choose to preserve their fertility before starting hormonal therapy or reconstructive surgery.
While egg freezing is becoming more popular, it still made up just 1.5% of the 68,000 fertility treatments carried out in 2016, HFEA statistics show.
It is also not a surefire way of having a child. Of those who had IVF with their own frozen eggs in 2016, less than one in five (18%) successfully conceived.
What does egg freezing involve?
The egg-freezing process typically takes between two and three weeks. A woman is first tested for any infectious diseases, like HIV.
An HIV+ patient can still freeze her eggs, however, they must be stored away from others’ to prevent contamination.
She then starts IVF, which involves up to two weeks of hormonal injections to stimulate the ovaries to produce multiple eggs.
When ready, the eggs are collected under general anaesthetic or sedation. Most women have around 15 eggs collected, however, it may be less for those with naturally low numbers.
Unlike IVF, the eggs are not then mixed with sperm but are instead added to a freezing solution. Vitrification, or fast freezing, may be more effective than the traditional method of cooling eggs slowly, research suggests.
READ MORE: Egg Freezing: 5 Things You Need to Know
Eggs frozen “electively” are then stored for up to a decade in liquid nitrogen. Cancer patients may be able to store their eggs for up to 55 years.
When ready for use, the eggs are thawed. Surviving ones are then injected with either a woman’s partner’s sperm or that of a donor, via a process called intracytoplasmic sperm injection (ICSI).
ICSI is necessary due to freezing making the outer coating of eggs tougher, with sperm being less able to penetrate the cell during IVF.
If fertilisation takes place, the embryo is then transferred into the womb in the hope it will lead to a healthy pregnancy.
When to freeze your eggs
When it comes to freezing your eggs, age is the single most important factor for success, according to the HFEA.
The organisation’s report “Should I freeze my eggs?”, states if a woman has the procedure at under 35, she will be more likely to conceive using these eggs than if she tried to become pregnant naturally, particularly from 40 and over.
The timing of egg freezing can be tricky to navigate. Law dictates if a woman freezes her eggs at 20, she has to use them by 30, however, she still may not be ready to have a baby at this age.
The fertility charity Progress Educational Trust argues this “arbitrary and outdated piece of legislation” pushes women to delay egg freezing until later in what it calls a “clear breach of human rights”, the BBC reported.
If she waits until her late thirties, her fertility is already in decline. She may therefore need to have several rounds of treatment to collect enough viable eggs for storage, creating both a financial and emotional strain.
Any change to the law is reportedly a matter for parliament.
To maximises their chances of success, older women often use frozen donor eggs rather than their own.
In the UK, it is illegal for a donor to be paid anything more than expenses, which are capped at £750 ($947.75) for an egg donor.
The donor has no rights or responsibilities in raising or financially supporting the child and is not mentioned on the birth certificate.
When the youngster reaches 18, however, they can find out their donor’s name, date of birth and address, and make contact if they wish.
Is egg freezing safe?
Egg freezing is generally considered very safe, according to the HFEA.
Some women may experience mild side effects from the hormonal injections, like tenderness at the site of the injection.
A third (33%) of those having IVF develop ovarian hyperstimulation syndrome (OHSS), with just over 1% of cases being moderate or severe, Royal College of Obstetricians & Gynaecologists (RCOG) statistics show.
OHSS comes about when the body overreacts to the fertility drugs used during IVF. The overstimulated ovaries swell and release chemicals into the blood.
Fluid from the blood vessels then leaks into the abdomen, and even sometimes into the heart and lungs. A small number of deaths have been reported, the RCOG reports.
Mild cases usually get better on their own, however, if a woman is vomiting, passing little urine or battling chest pain, she should go to hospital.
There is no specific treatment for OHSS, however, anti-sickness drugs and IV drips can replace fluids lost by vomiting.
Some studies suggest thawed eggs are more likely to result in miscarriage. However, considering only around 2,000 babies have been born via egg freezing worldwide, the evidence is limited, the HFEA states.
The cost of freezing your eggs
A select few are eligible for egg freezing on the NHS. For example, cancer patients about to start chemotherapy may be offered the procedure depending on where they live, according to the HFEA.
The rest usually have to foot the bill themselves, which can be costly. This is unregulated, with private clinics setting the price.
The collection and freezing process alone usually costs £3,350 ($4,298), while a woman can expect to spend up to £1,500 ($1,924) on the hormonal injections.
Eggs can be stored for up to a decade, with a woman usually paying up to £350 ($449) a year just to have her frozen eggs safely housed. The thawing and embryo transfer process then costs around £2,500 ($3,207).
All in all, a woman usually spends between £7,000 ($8,980) and £8,000 ($10,263) on freezing her eggs, with no guarantee it will end in pregnancy.
If successful, she may have frozen eggs left over. It is up to her whether she wants to donate them to research, training or someone else, or have them discarded.
Egg freezing outside of the UK
The procedure is reportedly also on the rise in the US, where women spend between $5,000 (£3,843) and $15,000 (£11,545) preserving their fertility, coparents.com reports.
While it may seem harmless, egg freezing has taken a controversial turn in Poland. With 86% of its residents identifying as Catholic and the Vatican fiercely against IVF, a “compromise law” was passed in June 2015, The New Yorker reported.
The legislation states IVF is only available to heterosexual couples who are married or cohabiting.
This has left single women effectively “blocked” from accessing their own frozen embryos unless they can convince a male in their life to sign a document, pledging legal and financial responsibility for the child.
Moreover, to ensure frozen embryos are not destroyed. They must be donated to infertile heterosexual couples if not used within 20 years.