Wednesday, 4th October 2023

Breakthrough on use of IVF for sex selection, children with two fathers

By Chukwuma Muanya
06 April 2023   |   3:18 am
Scientists are divided over recent advances on using In Vitro Fertilisation (IVF) for sex selection with over 80 per cent success and children with two fathers. They said the second technique could pave the way to allowing two men to have children together.

Pregnant Woman

•Using PGP ensures ‘normal’ babies, prevents birth of sickle cell disease with 99.9% success
•British scientists, Ashiru call for urgent IVF regulation as method raises ethical issues

Scientists are divided over recent advances on using In Vitro Fertilisation (IVF) for sex selection with over 80 per cent success and children with two fathers. They said the second technique could pave the way to allowing two men to have children together.

Reacting to the findings, a Joint pioneer of In Vitro Fertilisation (IVF)/Test Tube Baby technology in Nigeria and Medical Director, Medical Art Centre (MART) Clinic Maryland, Lagos, Prof. Oladapo Ashiru, told The Guardian that sex selection through any method raises ethical issues and some countries accept it while some have banned it.

Sex selection is currently banned in several countries including Britain, Canada and Australia for non-medical reasons, such as when a child is at risk of a gender-specific inherited condition. Although the practice is not encouraged in the US, it is also not banned.

Ashiru explained: “I am aware of this research. For me, it is too early to make a critique of the process. It is very common with new breakthroughs for many to jump and criticize. Even at the beginning in 1976 when Steptoe and Edward’s report success with IVF-Embryo Transfer (ET) but resulted in ectopic pregnancy, they were vilified by the science community. But they persevered and by 1978 Louise Brown was born and became the first test tube baby in the world. Today IVF-ET is now an accepted technology with almost 10 million babies born through it.”

Ashiru, who is also the President, African Fertility Society (AFS) and Association of Medical Specialties in Nigeria (AMSN), said MART Clinic started Pre-Implantation Genetic Testing (PGT) in Nigeria almost 20 years ago and the indication was to prevent abnormalities in babies, especially with patients with recurrent IVF failure, those with advanced maternal age, and later for those who can transfer abnormalities to their babies, like sickle cell disease carriers.

The fertility expert said through this method, MART Clinic has been able to help bring to the world, normal babies, and prevent the birth of sickle cell disease babies for sickle cell carrier couples. He said, in comparison to the new method that has 80 per cent success; the PGT is 99.9 per cent successful. “In my opinion, the jury is still out on this new method and time would tell,” he said.

Indeed, researchers have developed a new technique that appears to be safe and around 80 percent effective in producing babies of the desired sex.

The researchers, including Professor Gianpiero Palermo from Weill
Cornell Medicine in New York City, United States, said the technique is “extremely safe as well as efficient, inexpensive, and ethically palatable.”

But the issue of sex selection still raises serious ethical concerns, and the selection of embryos on the basis of sex, without mitigating reasons such as sex-linked disease, is illegal in many countries.

While the use of this technology to select a child’s gender is not illegal in America, its use remains highly controversial.

Researchers, who published their findings in PLOS One, set out a technique to separate and select the sperm beforehand, meaning the sex of the embryos could be determined.

The authors selected sperm based on whether they contained an X chromosome (making female offspring) or a Y chromosome (making male offspring), using density measures.

Sperm that contains an X chromosome are slightly heavier than sperm containing a Y chromosome, the study suggests.

The researchers wrote: “Although ethically debatable, expressing a sex preference for offspring is popular among couples, and not limited to those undergoing infertility treatment.

“Sperm sex enrichment… enables the selection of embryos for the desired sex. Our sex selection method does not increase the proportion of additional aneuploid embryos. Therefore, it can be regarded as extremely safe as well as efficient, inexpensive, and ethically palatable.”

There are no restrictions on using technology to choose the sex of a child before it is born in the US.

However, in the United Kingdom (UK), as in almost every other country, choosing your child’s gender is banned outside of specific circumstances.

Experts believe alcohol reduces the amount and viability of sperm, making it more difficult to fertilize the female egg.

The small trial was conducted using 1,317 couples and split into two groups, with 105 men in the study group in which the new technique was used.

According to the study, 59 couples in this group desired female offspring and the technique resulted in 79.1 per cent (231/292) female embryos.

This brought about the birth of 16 girls without any abnormalities.
Forty-six couples desiring male offspring ended up with 79.6 per cent male embryos (223/280), resulting in the birth of 13 healthy baby boys.


However, in the study, the sex of the embryo chosen for transfer was not known.
Professor of genetics at the University of Kent, in the UK, Darren Griffin, said: “The issue of sex selection is an ethically fraught one. Selection of embryos on the basis of sex, without mitigating reason such as sex-linked disease, is illegal.

“Separating sperm beforehand may provide a legal loophole in some countries but not the UK. There have been numerous methods around for decades, some effective but potentially harmful, others dubious in their effectiveness.

“I am convinced that the science is sound and that, instead of the usual 50:50 ‘coin toss’, a couple can get a baby with the desired sex a little under 80 percent of the time.”

Head of Andrology at Imperial College London, also in England, Dr. Channa Jayasena, said: “The results show convincingly that this technique is able to select sperm to determine the sex of embryos made using those sperm.

“However, their technical achievement is insignificant compared to the serious ethical concerns raised by the research.”

He continued, pointing out the potential issues this type of research runs into.

“However, they propose sperm selection as an ‘ethical’ alternative to embryo selection. I find this incredible since sperm selection is just another way of selecting embryos to manipulate the sex of offspring, with detrimental societal implications,” he said.

He added: “Though not described in the study, their technique might be adapted in the future to select for other bodily traits such as sperm containing a gene affecting skin or eye colour.

This research, therefore, raises ethical severe concerns which need to be addressed urgently through regulation.”

The researchers concluded: “Currently, couples seeking pregnancy through IVF will usually undergo the process of pre-implantation genetic diagnosis (PGD).

“This process scans the fertilized embryo for genetic disorders when it is in its earliest stages. It can also tell the parents their child’s gender.

“It allows parents to get information about the embryo before it is implanted in a woman to be incubated. Experts say PGD is around 99 per cent accurate.

This process requires fertilization, though. The Cornell researchers’ new method can detect whether the child will be male or female by using a sperm cell alone.

“For some, who may be uneasy about discarding a fertilized embryo, this new process could be less morally dubious.”

Meanwhile, British scientists have called for urgent regulation after US researchers unveiled a new technique that would allow parents to easily pick the sex of their child during IVF.

Currently selecting the sex of an embryo is banned in the UK for non-medical reasons, but the new process involves choosing the correct sperm, which increases the odds of having a boy or a girl to around 80 per cent.

British experts warned that the technique could provide a legal loophole that would allow couples to choose the sex of their child.

Also, scientists said they have created mice with two fathers by producing eggs from male cells, in research that has the potential to open up radical developments for human reproduction.

The technique could pave the way to allowing two men to have children related to both fathers, and could also treat a type of infertility in women.

However, scientists said much more research would need to be done and ethical considerations made before this would be considered in humans.

Prof Katsuhiko Hayashi from Osaka University presented his findings -which is not yet published – to the International Summit on Human Genome Editing at the Francis Crick Institute in London.

The research involved creating a stem cell from a skin cell of a male mouse, and then deleting the Y chromosome and duplicating the X chromosome, allowing it to turn into an egg.

Just seven pups were born from 600 attempted implants. But these pups went on to live healthy lives, and have offspring of their own.

It is not the first time similar attempts have been made.

In 2018, scientists at the Chinese Academy of Science successfully bred mice from two fathers, but the pups were unhealthy and died after a short time.

Prof Hayashi, a world-renowned expert in the field, told the summit that he is working on developing fertility treatments.

He believes his work could potentially be available for humans in ten years.

“If people want it and if society accepts such a technology then yes, I’m for it,” he told the BBC.

But he added: “Even in mice there are many problems in the quality of the egg. So before we can think of it as a fertility treatment we have to overcome these problems, which could take a long time.”

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