When Louise Brown was born in Manchester in July 1978, her parents’ neighbors were shocked to discover that the world’s first test tube baby was “normal”: two eyes, ten fingers and ten toes. In the 45 years since then, IVF has become the world’s leading treatment for infertility. At least 12 million people have been visualized among test tubes.
Every 45 seconds or so, an IVF baby is born, taking their first breaths of air. IVF babies are as healthy and normal as everyone else, yet their parents, most of whom struggle for months or years with infertility, are nothing short of a miracle.
1 in 6 people suffer from infertility
In a world where one in six people suffer from infertility, these successes are rightfully celebrated. What is less controversial are the problems with in vitro fertilization. Most treatments fail. This subjects women and couples to cycles of hope and frustration, and gives the assisted reproductive industry an incentive to sell false hope. The obstacle is the lack of progress in understanding the underlying mechanisms that determine fertility. Now, finally, science is making progress, offering more hope and less suffering for future generations of parents.
Over the years, IVF has made its techniques better and safer for the women who bear the brunt of the treatment. The birth rate of twins and triplets has decreased, which has reduced the number of risky pregnancies. Safer hormonal treatments. Combined with egg and sperm freezing, donation, and surrogacy, IVF has given many people (including same-sex couples and singles) a chance to be parents they never had before.
However, the process is still tiring and expensive. It is physically painful for women and emotionally draining for both sexes. For many, fertility treatment is an unaffordable luxury; In the United States, for example, a course can cost $20,000. Some countries restrict processing according to conservative ethical codes. Until 2021, French law only allowed IVF marriages to heterosexual couples. Many countries, including China, ban egg freezing, which helps extend childbearing years.
Often, the pain and cost end up being lost. The 770,000 babies born via IVF in 2018 required around 3 million cycles. Many women undergo hormonal injections round after round, sometimes going from clinic to clinic. In the United States and Great Britain, almost half of them go home with a baby in their arms, sometimes after several years of trying and up to eight courses of treatment.
All of this has fostered a sector of assisted reproduction that sells to clients who have become regulars and desperately need to conceive. When a course fails, many clinics offer poorly structured lists of “add-ons” that do not clearly increase the chances of success, or may reduce them. They charge hundreds of thousands of dollars for treatment.
All of these problems share a root cause. Although reproduction is a fundamental aspect of human biology, scientists have surprisingly limited knowledge of how new life arose. The essential is clear: the sperm and egg must meet. However, many of the cellular, molecular, and genetic underpinnings of pregnancy remain a mystery.
Little is known about how a woman’s ovarian reserve is built before childbirth; Or why eggs decrease in number and quality until menopause, which is known among mammals only in humans and in five species of whales. Also mysterious are the complexities of how the fetus enters the uterus and connects to the blood supply. Infertility is often grouped under “women’s health” issues, but male factors play at least some role in about half of infertile heterosexual couples, even if that role is often not clear.
Against all this, IVF is woefully inadequate. It arose as a solution to the blockage of the fallopian tubes that prevented Lucy Brown’s mother from becoming pregnant. Today, with more couples trying to conceive at a later age, it is increasingly likely that the problem is a woman’s low egg count. There, in vitro fertilization works by providing more opportunities, collecting more eggs and increasing the chances of them being fertilized. This procedure works for the lucky few, but without entirely new approaches and treatments, many prospective parents will suffer one disappointment after another.
Some recent scientific work offers some hope. In Japan and the United States, researchers are harnessing stem cells — which have the potential to become any of the body’s many specialized tissues — to produce eggs from skin and blood cells, a process called gametogenesis in vitro. In Japan, healthy rat pups were created from cells originating from the tip of their mothers’ tails. Earlier this year, researchers announced that they had successfully bred mice that share two genetic parents. One contributed sperm and the other skin, which first became stem cells and then eggs.
There are teams working to apply these technologies to humans. There is still much to be seen if cells safe enough to give birth to healthy babies will be available at any time. However, the research provides new insights into how sperm and eggs are produced. The process of in vitro morphogenesis means that researchers will no longer have to rely on donated eggs, sperm, and embryos in their studies; It is often given generously by IVF patients. Other teams are using stem cells to build models of embryos (called “embryos”). You’ll never see these fetuses inside the womb, but they can help show what happens to real fetuses that do.
Over time, new treatments may emerge. Same-sex couples can have children who are genetically related to them as can heterosexual couples. Transgender people who undergo a gender change can do so without sacrificing their fertility.
All this will take time. This is why in vitro fertilization will continue to be important and why it needs investment and regulation. A better understanding of fertility should help increase the success rate of IVF and reduce its emotional and financial costs. The new treatments could herald the biggest shift in assisted reproductive technology since the birth of Lucy Brown. Surveys show that many countries have fewer children than would be desirable, in part because motherhood has been postponed. If the sexual revolution of the 1960s and 1970s gave women the option not to have children if they didn’t want to, the emerging technology could herald a new revolution that will allow women (and men) to have the children they want, when they want.
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