n 1977, two British scientists combined a sperm and egg in a petri dish.
A year later Louise Brown, the world's first "test tube baby" was born.
At the time, the pioneering technique seemed like something out of science fiction, but more than 5 million babies later, in vitro fertilization (IVF) has become commonplace in assisted reproductive technology.
Now, nearly 40 years later a baby boy has been born with DNA from three people. It's a revolutionary step that allows parents with rare genetic mutations to have healthy babies.
This latest breakthrough is one of many advancements in the field of fertility that scientists expect will change the way babies are created.
Every day researchers around the world are working toward making fertility treatments cheaper, safer, and easier.
Healthline looked at three ways fertility treatments could change in the coming decades.
Babies born without eggs
Scientists in England say their research suggests it may one day be possible to create babies without the need for an egg from a female.
The researchers started with tricking an egg into developing into an embryo without being fertilized. Usually, the pseudo-embryos that form in this instance (called parthenogenotes) die after a few days as they lack key development processes that only happen with input from sperm.
But scientists found they were able to create healthy baby mice by injecting the parthenogenotes with sperm.
Parthenogenotes have much in common with regular non-egg cells (such as skin cells) in the way they divide their DNA. Researchers have concluded that if healthy babies could be created from injecting sperm into these pseudo-embryos, the same process could create human babies from non-egg cells.
The findings, published in Nature Communications, challenges two centuries worth of understanding of fertilization.
"It had been thought that only an egg cell was capable of reprogramming sperm to allow embryonic development to take place," Tony Perry, Ph.D., molecular embryologist at the University of Bath, and senior author of the study, said in a press release.
"Our work challenges the dogma, held since early embryologists first observed mammalian eggs around 1827 and observed fertilization 50 years later, that only an egg cell fertilized with a sperm cell can result in a live mammalian birth."
The research could change the way babies are created, by eliminating the need for a female participant altogether.
Removing the need for an egg could theoretically mean that two males could conceive a child, with one donating an ordinary cell (such as a skin cell) and the other donating sperm.
Although Perry told the BBC such scenarios are "speculative and fanciful" at this stage, he says it could be a possibility in the distant future.
Drug-free fertility treatments
Although IVF is a common option for those struggling with infertility, researchers in Australia and Belgium say they have discovered a less expensive and less invasive alternative.
The researchers were able to enhance an already existing fertility treatment called in vitro maturation (IVM) by improving the quality of egg cells using growth factors.
In a standard IVF procedure, women are required to take follicle stimulating hormones to promote egg cell growth before they are removed from the ovary.
IVM instead retrieves eggs from the ovary while they are in the immature stages. IVF has commonly been the preferred method as pregnancy rates after IVM have been lower.
However, scientists in Australia and Brussels, led by Associate Professor Robert Gilchrist from the University of New South Wales, have improved the IVM process using a growth factor called cumulin. The lab at UNSW is one of only two in the world that make the growth factor.
"The aim of our research has been to restore, as far as possible, the natural processes that occur during egg maturation," said Gilchrist, who is based at UNSW's School of Women's and Children's Health, in a statement.
"We have demonstrated that it is possible to improve egg quality and embryo yield with next to no drugs, using potent growth factors produced by the egg."
The technique is the result of 15 years of research and is currently awaiting U.S. Food and Drug Administration (FDA) approval.
Preliminary experiments using the enhanced IVM technique in pigs showed an improvement in the quality of eggs and a doubling of the embryo yield (when compared with the standard IVM method). In a pre-clinical trial on human eggs in Brussels, researchers found a 50 percent increase in embryo yield.
The research is an advancement in fertility treatment because if it is accepted into clinical practice it will remove the need for women to inject high doses of hormones over several weeks.
Scientists hope the enhanced IVM method will help women avoid discomfort and medical complications, and will also provide a cheaper alternative to IVF.
Lab-made sperm
Scientists in Spain say we could be closer to eliminating the need for sperm or egg donors.
Earlier this year scientists created human sperm using skin cells.
The work, carried out in collaboration with the Valencian Infertility Institute and Stanford University could provide a solution for the 15 percent of couples around the world who are unable to conceive and must turn to donated sperm or eggs.
The researchers injected mature skin cells with a cocktail of genes to create gametes (sperm or eggs). After a month the skin cells had transformed into a germ cell, which could then develop into a sperm or an egg. However, the cells did not have the ability to fertilize.
Dr. Carlos Simon, scientific director of the Valencian Infertility Institute, says being able to create sperm or eggs in a lab setting could give hope to those who have been unable to conceive.
"(The) generation of artificial gametes is a great promise for all those couples that, for many different reasons, currently need to go to gamete donation for fulfilling their wish to have children but would prefer to have genetically related offspring," he told Healthline.
Although the research is likely to take a decade before it could be implemented for human use, Simon says that such research may in the future eliminate the need for sperm or egg donors entirely.
"I am sure that it will happen," Simon said. "Reproduction is more important than we think and regulators must prepare the legal ground for the future ... the scientific revolution will change the way that reproductive medicine is done."
By Elizabeth Pratt
The original article was published on Healthline.com.