© The Indian Express Pvt Ltd
Tags:
Journalism of Courage
A baby boy has been born to an US couple developed from an embryo that had been frozen for more than 30 years in what is believed to be a record length of storage time before a birth.
Through a process called the embryo adoption, which is in use in the US to help infertile couples with unused and leftover eggs from a bank, Lindsey and Tim Pierce used a handful of embryos donated in 1994. The donor woman had four frozen embryos, one of which resulted in the birth of her own child and three of which she preserved and then donated for use by others. The donated embryo has been in storage for 11,148 days, which the Pierces’ doctor says sets a record.
“If the embryo quality is good and the freezing is done as per accepted standards, an embryo can last decades. Mind you this was a procedure done in 1994. Now there have been so many advancements to preserve the embryo. Many mistakenly believe that the baby would be born abnormal if the embryo is frozen for a long time. Fact is freezing keeps a healthy embryo as it is,” says Dr Anjali Malpani, infertility specialist and emeritus professor of Gynaecology and Obstetrics, Seth G S Medical College and KEM Hospital, Mumbai.
First, the woman’s egg is harvested and fertilized by the man’s sperm outside the body, in a laboratory. This is what we call in-vitro fertilisation or IVF. The freshly-harvested embryos are then transferred to a woman’s uterus if the couple wants a baby immediately or preserved for later implantation.
During IVF, several mature eggs are retrieved from the woman’s ovaries and are then mixed with sperm in a laboratory dish. While many sperm will be in contact with each egg, only one sperm will successfully fertilize each egg. So multiple embryos can be harvested in a single IVF cycle. However, only up to two embryos are implanted at a time. What matters is the quality of the embryo. Implanting more won’t necessarily change the possibility.
The embryos are then frozen through a process called cryopreservation, which involves gradually cooling them to extremely low temperatures in liquid nitrogen, to halt all biological activity and preserve them for future use. This process allows for the indefinite storage of embryos and also retains their quality as is for later thawing and transfer. The embryo is as good as a freshly harvested one.
That the baby could be born abnormal because of it. Today, because of advancements in science and biotechnology, the number of years doesn’t matter if the embryo is preserved properly in a certified laboratory. The second most important factor is harvesting of quality embryos by a trained embryologist.
In the early days, it was a slow-freezing process, so ice crystals would form, damaging the cell matrix of the embryo. Only two out of 10 embryos would survive on thawing. In these days of flash-freezing, the crystallisation is minimal. The optimal temperature for preservation is minus 196 degrees centigrade. And in a good lab, all 10 embryos are good for implanting, which means a 100 per cent recovery on thawing. While ovaries get old, the uterus doesn’t. So a woman can have a baby in her later years with the frozen embryo. The chances of birth defects are lower than if the woman had done an IVF at 40.
I have had women who froze the embryo with the help of their partners and had them implanted after 10-12 years when they were more settled in life. Cryopreservation has given young people options to choose when to have their child.
It costs anywhere between Rs 30,000 to Rs 60,000 annually. But choose a good lab.
You can freeze an embryo for any number of years. In India, however, the law says that you cannot keep an embryo frozen beyond 10 years. After that a couple has to donate it for research or to other couples.
