Having a baby is a dream come true for many women and 39-year-old Rungnapa (not her real name) is no exception. She has had a deep yearning to conceive since she was in her 20s.
"Being a mother is a wonderful experience," said Rungnapa "Holding and cuddling a little baby would make me feel on top of the world. And simply watching him or her grow and knowing that he or she gives me unconditional love would be the icing on the cake.
"When seeing someone else's child, I feel a physical and an emotional tug. I have to force myself not to stare at the child," added the successful businesswoman, who doesn't have a partner, yet.
However, hoping to conceive a child later in life, Rungnapa decided to have her eggs frozen at a fertility centre five months ago.
"I hope I find the right man whom I want to share my life with. And I don't want age to stop me from conceiving," said Rungnapa, who hopes to have her frozen eggs fertilised with her future husband's sperm and then implanted into her uterus.
Even though Rungnapa is resigned to that fact that freezing her eggs is a not fail-safe method, the procedure, she said, is worthwhile.
"I've learned that my chances of getting pregnant are very slim now due to my age," said Rungnapa.
"My doctor told me that my eggs may not survive the freezing process nor may they produce viable embryos when they are fertilised.
"However, I prefer to take the chance. I could be lucky enough to experience parenthood later in life.
"Freezing one's eggs is a good option for older women, as it allows us to better control our reproductive future," she said. "We have to spend many years developing a good career and many of us want to have a child when we are financially sound, to ensure that the child has a bright future."
Rungnapa is one of the modern group of women who are having their eggs frozen before their quality declines. Most women reach their fertility peak in their early 20s, then things slow down when they are in their late 20s.
The eggs are stored in a cryopreservation straw and then placed in a batch of liquid nitrogen.
At the age of 35, fertility declines and by the age of 38, the downward slope of fertility continues rapidly, meaning that the chances of getting pregnant become less and less. And a woman's chance of conceiving each month by the age of 40 is about 5%, and drops to 1% by the age of 45.
According to Dr Somjate Manipal-viratn, clinical director of Superior ART, ovaries are not only responsible for producing eggs but also producing hormones.
As women age, their reproductive capabilities slow down, and they are less effective at producing mature, healthy eggs. When getting close to menopause, the ovaries respond less to the hormones that help ovulation.
"The decline in fertility is a natural process that happens in healthy women," the fertility specialist said. "But vices such as smoking can speed up the decline in fertility."
''Menstruating doesn't necessarily mean that conception will happen,'' the doctor said. ''Many women underestimate the fertility issue. They don't care much about it until they consider having a family,'' he said, adding that the number of women with inadequate fertility awareness is on the rise.
Fertility preservation can be complicated. It starts with a visit to a fertility specialist who counsels and evaluates the need for the procedure. If the woman is a good candidate, she is required to have a blood test to assess her fertility.
''Not every woman who desires to freeze her eggs is a good candidate for the procedure,'' Dr Somjate said. ''Fertility testing can help predict if we will get enough eggs to make the procedure useful. If the results are not satisfactory, it may waste time and money.''
The woman will be given fertility medication for nine to 12 days to stimulate the ovaries in order to produce a number of mature follicles _ fluid filled sacs containing eggs. During this time, Dr Somjate said, the candidate will be monitored closely to prevent overstimulation, which can cause serious medical conditions and in rare cases, death.
''The process of ovary stimulation was tough for me,'' said Rungnapa. ''I had to watch every step and be very careful with everything I did. My stomach bloated like a balloon, and I had pregnancy-like symptoms. I felt very emotional during that time. It was almost as though I was really pregnant,'' she recalled.
About two days later, a specialist collected 10 eggs using an ultrasound-guided needle, which is inserted through the vagina while the woman is under mild sedation.
''Most women feel little pain and a bit of cramping during the harvest process. They can go back to work the next day,'' Dr Somjate said. The eggs are immediately frozen, Pagawadee Ketcharoon, an embryologist added, using vitrification or snap freezing to avoid ice crystals that can form inside the eggs, which can damage their genetic material. They are stored in liquid nitrogen at -196C.
''About 95% of eggs preserved using the snap freezing process survive the thawing process,'' the embryologist said.
When the woman decides to become pregnant, the egg will be thawed slowly. The process involves a carefully controlled drop in temperature before being warmed up again. By using ICSI (Intracytoplasmic Sperm Injection) and IVF (in-vitro fertilisation) the egg is then implanted into her uterus. If the procedure is successful, the woman becomes pregnant.
''Because the eggs are stored in liquid nitrogen, they could last up to a decade,'' said Pagawadee, adding that most eggs are used within a few years after being frozen.
''Family planning is an important step for healthy living,'' Dr Somjate said. ''If a woman really wants to have a baby, she should make it a priority and have one at an appropriate age.'' The doctor said that Thais overlook the idea of leading a happy single life or even leading a happily married life, without children.
''The inability to have a biological child is not the end of the world. If you love children, adoption is a good option,'' he said. The process of egg freezing costs between 130,000 to 150,000 baht on an average, when performed at a private fertility centre.
Rungnapa said that although her eggs may not work when she thaws them out, it was worth the financial risk.
''To me, spending thousands of baht on my reproductive future is inexpensive. Feelings and emotions cannot be measured in absolute value. Having a baby will fulfil my dreams and can improve my quality of life.''