From putting our fertility on ice, to a new if highly controversial procedure which requires genetic material from three people to make a baby, we take a look at some of the latest news and breakthroughs in fertility treatment from around the world.MRT (mitochondrial replacement therapy) or “three-person IVF”In 2018, a 32-year-old Greek woman, who’d previously undergone four rounds of IVF and two operations for endometriosis, caused a stir when it was revealed her doctors were using a controversial fertility treatment – Mitochondrial Replacement Therapy (or MRT) – in an effort to help her get pregnant. In April of this year, she gave birth to a healthy baby boy thanks to the procedure – although technically speaking, he has genetic material from three parents. What is MRT?While the idea of Mitochondrial Replacement Therapy has been around since the 90s and even produced some births in the US, it was banned by the US Food and Drug Administration in 2001.The process involves harvesting eggs from a donor, removing their nuclei, and then inserting DNA from the mother in their place before inseminating the modified eggs and transferring the resulting embryos to the mother’s womb.Mitochondria, as you may remember from school biology classes, are the ‘powerhouses of the cell’, converting nutrients into energy through cellular respiration. They are found in all cells - and they contain their own DNA. Every human alive today possesses mitochondrial DNA which they inherited from their mothers, although it only makes up about 1% of our overall DNA complement. Because donor eggs used in the process of MRT will contain their own mitochondria (and therefore their own DNA), embryos created and children born through this process will carry a tiny fraction, albeit only about 0.2%, of a third parent’s DNA. What are the applications for MRT?This process, which was given the go-ahead for trials in the UK in 2018, has two main applications. For women with mitochondrial diseases, the procedure can eliminate the risk of their passing a potentially deadly condition on to their children. The more controversial use of MRT is a fertility treatment option for women who have been unsuccessful with traditional IVF treatment. As yet, some scientists argue, we don’t have sufficient data on the risks of that 0.2% ‘other’ DNA to warrant its use over existing fertility treatment options. Fertility on ice – the rising trend in egg freezingFor women approaching their 30th birthday, there’s an entirely different way to mark the occasion which is becoming more and more popular – freezing some of their eggs so they can continue to focus on their career now while keeping the option to start a family open later. While society and the role which women play might have changed dramatically, our biology, sadly, has not kept pace. And while fertility science enjoys some of the most rapid advances, improvements and innovations in the medical field, a woman’s age (or more accurately the age of her eggs) is still predominantly the most significant factor in whether she’ll have a successful pregnancy or not. The process of egg freezing involves harvesting eggs from a woman’s ovaries and placing them in a state of deep freeze using liquid nitrogen until they're ready to be thawed and used. The procedure has become impressively successful, with birth rates using frozen eggs now comparable to using fresh ones. In addition, IVF treatment is also becoming safer – with a marked decline in the cases of multiple births (which are riskier than single childbirths). But listen up fellas, because it’s not just women whose biological clocks are ticking……and sperm freezing Over the past few years, several studies on the effects of ‘advanced’ paternal age on the resulting offspring have made the news, indicating possible links between older fathers (we’re talking about 35 and above) and autism, risk of miscarriage and birth defects, epilepsy and schizophrenia in children.Gloria Bachmann, MD, and the director of the Women's Health Institute at Rutgers Robert Wood Johnson Medical School explains:“Just as people lose muscle strength, flexibility, and endurance with age, in men, sperm also tend to lose 'fitness' over the life cycle… As a society, perhaps men should be encouraged to bank sperm before their 35th or, at least, their 45th birthday, to decrease the increased risks on maternal and fetal and child health which have been shown to occur as a result of aging sperm.” Heterosexual couples who want children but feel they are not yet in a financial position to start their family may well want to undergo egg and sperm freezing as a joint venture! And for the survival of the species in an entirely different context, an intriguing Spanish study has found that frozen sperm is able to maintain its viability in outer space conditions.