Women are being fed an experimental cocktail of super-nutrients in the hope this will reduce their children's risk of obesity and diabetes as adults.
About 1800 women in Auckland, Singapore and England will participate in the trial, which aims to reduce pregnancy-related diabetes and thus switch genes to the right settings for the baby's best shot at good health long term.
It involves twice-daily consumption of one of two kinds of health drink, starting before conception and continuing through pregnancy. The sachet's contents, mixed with water, is either vitamin and mineral supplements, including folic acid, or that plus probiotics and a supplement called myo-inositol.
The body needs myo-inositol for making cell membranes and other functions. It is related to inositol, which is present in nuts, legumes and cereals. Food company Nestle, whose research division is one of the trial's partners, has filed a patent claiming that myo-inositol with probiotics could help prevent pregnancy-related "gestational" diabetes.
The influential Cochrane Collaboration's analysis of myo-inositol studies last year found it shows promise as a dietary supplement during pregnancy to prevent gestational diabetes, "but there is not enough evidence at this stage to support its routine use".
The University of Auckland's Liggins Institute, which is running the New Zealand part of the trial, says the research indicates the food women eat, even before they are pregnant, can programme a baby's genes to switch on or off, influencing its risk of obesity.
Liggins researcher Professor Wayne Cutfield said that by better regulating the mother's blood-glucose levels, the experimental drink is intended to reduce risks to the fetus by "minimising the load of glucose and calories".
Lead researcher Professor Keith Godfrey, of the University of Southampton in England, said, "We think these extra supplements might switch genes on and off in a way that helps maintain healthy mother's blood-sugar levels during pregnancy. This may protect babies against obesity in later childhood."
Professor Cutfield said the study will hopefully be extended to follow the children throughout childhood.
The women in the trial are randomly assigned to receive the experimental drink or the standard one and don't know which they are given; nor will the researchers, until they analyse the results.
Harry Fox Perwick, of Torbay, Auckland, is the first baby born in the trial. Weighing 2.935kg, he arrived at North Shore Hospital on April 28. He is the first child of Rebecca Perwick, aged 27, who said the delivery was straightforward and very quick.
She joined the trial because, as a research technician at the university, she saw an internal email "looking for people interested in an area of research that's quite important".
Nutrition is important, she said, and, if not for the trial, she would have taken the recommended folic acid and iodine supplements.
Mrs Perwick said the drink tasted fine, but was hard to take when she felt nauseous.
Harry is thriving and while Mrs Perwick estimates she is getting 6-7 hours sleep, the interruptions to her sleep are, "a bit of a shock to the system".
Feeding the mum
• Trial of a new kind of dietary supplement
• Before conception and during pregnancy
• This could set up the baby's genes for lower risk of obesity and diabetesMartin Johnston health