Quadruplets James, Joshua, Lauren and Emily Turner have beaten odds of 70 million to one because they are not only a foursome but also two sets of identical twins – born last month by caesarean section at 29 weeks. Last Friday, when they made their debut in the national press, their father, Julian, reported the good news that they are "getting bigger and stronger every day".

The siblings are a miracle of modern medicine, not least because their mother, Sharon, had had three unsuccessful rounds of IVF before conceiving at the fourth attempt. The Turners have become rich beyond their dream of parenthood, since initially they were told they were expecting one child – but also poorer by £40,000, the bill for IVF .

Today, the business of having a child is a veritable global commercialised baby machine with the ties that bind resembling a profoundly tangled knot. It is possible, for instance, for a baby to have several parents. Imagine a biological mother who may be Indian, carrying another woman's egg, say from eastern Europe, fertilised by a third party, perhaps an American donor, to be handed at birth to the one or two "social" parents, of same or different genders, who undertake the rearing somewhere in the UK.

According to research, the offspring will turn out as well as those created in a more orthodox manner if there is good enough loving. However, given that women may now give their eggs in return for a free cycle of IVF, it is also possible for a person who has remained childless to meet "her" son or daughter, carried to term by another woman. All of which requires a far more complicated answer to the age-old question much loved by children – "Where did I come from, Mummy?"

Precisely how complicated was among the issues discussed at an impressive (not least for its honesty) clinical symposium, "Making Tomorrow's People", last Thursday, organised by the Great Ormond Street hospital for children NHS foundation trust. It was the first conference of its kind to consider the ethics, dilemmas, values and sometimes unseen consequences that arise from the ability not only to alter the odds of birth, life and death, but also select and "choose between different possible future people" – by gender and physical and mental characteristics.

The struggle to create and preserve the life of a much desired child is, at present, most often a very private affair brokered between professionals and families. Arguably, however, there is a public debate to be had about the beginnings of life that is as difficult and value-laden, but as vital, as the one we are belatedly beginning to conduct about the end of life. The question posed by professionals last Thursday in assessing the ethics that justify their ability to intervene on an unprecedented scale is one that perhaps ought to involve us all: "Just because we can – should we?"

Many parents would have an understandably direct response – an unqualified yes. Today, genetic profiling of embryos prior to implantation can screen out particular diseases while operations in the womb and technological breakthroughs mean that those born pre-term at 23, 24 and 25 weeks who were previously unlikely to survive have up to a 50% chance of a relatively good health. Neuroimaging in the womb can chart a baby's progress or distressing lack of it, while neonatal surgery of the most delicate and intricate kind corrects major malformations within hours and days of a baby's birth.

The simple axiom is that benefit should outweigh the burden and that quality of life counts. But that is to strip such decisions of all the love, anxieties and grief that come from knowing your newborn baby covered in technology in intensive care dies because of how terms such as "quality of life", "benefit" and "burden" are defined. But we need to be clear that with finite resources, heavy investment in preserving the lives of a small number of newborns does mean less investment for the majority of children in later years. It was almost easier in the past when medical ingenuity and skill couldn't meet the challenge and there was no NHS to fund advances.

There is a further dilemma. Twenty years ago, paediatric intensive care units were full of babies with head injuries, pneumonia and acute diseases. Now, they are more likely to be neonatal survivors. While up to 50% of pre-term babies may flourish, the other half could face a lifetime of expensive and continued medical support, pain and limitations. Again, 10 years ago, a baby with Edward's syndrome, a genetic condition, wouldn't have survived more than a few days. Now, some live for "10 happy years". Among the symptoms they endure are heart and kidney problems, breathing difficulties, hernias, bone abnormalities, lung infections and a severe learning disability.

We were told at the symposium about babies with spina bifida who grow to live lives, both ordinary and extraordinary. But there are other children who, at 14 or 15, say they wish they had never been born and end their lives. The dilemma is that in any one cohort, who knows who will flourish and who will fade? And who has the right to decide? What is certain is that such children do not exist in a vacuum. They live in a society in which support for those with added challenges is being severely curtailed. In addition, the UK has an abysmal record for caring for the health of the wider child population. As we shy away from opening up difficult discussions and acknowledging that priorities matter, injustices and crises on a significant scale are already happening by default – the worst of all situations.

We have the highest mortality rate for the under-16s in western Europe. Sixteen hundred children a year die from treatable diseases such as asthma and pneumonia. According to Dr Hilary Cass, president of the Royal College of Paediatrics and Child Health, speaking last Thursday, only 3% of children with asthma and only 4% of children with diabetes have a care plan. We have too many paediatric units and too few middle-ranking paediatricians. We need fewer hospitals and more care in the community to cope with chronic conditions such as the dreadful consequences of one in three of our children being overweight by the age of nine. That means we, the public, being mature enough to stop insisting that every hospital stays open, regardless.

Forty years ago, the Court report said paediatric care was too fragmented, not community-based enough. While pioneers have pushed forward the frontiers of medicine in spectacular fashion in some areas, the basics of childcare and the vital investment in prevention (and that means tackling poverty as well as the obesity epidemic) remain shamefully frozen in the past. How this is changed should not be left to professionals, parents under duress and commissioners trying to do more and more with less and less. We all have to find a voice. A child's future is rarely fair but at least we can assess better the true price that's paid