Mr Gascoigne took Menevit, a vitamin already available to aid men's fertility, but two more IVF cycles produced poor quality embryos.
So Mr Gascoigne said he "went on the internet, to the library, talked to the lawn mower man, to blokes at the gym" about what he could do, finally identifying nine key ingredients which he began taking daily.
At the next IVF cycle the couple produced three of the highest grade embryos, one of which became 18-month-old daughter Ava. Mr Gascoigne is now marketing the ingredients as Vitamenz, on his website.
However, reproductive medical specialist and Fertility Associates Hamilton director Dr VP Singh said vitamins' efficacy should be scientifically proven through randomised controlled trials, as new drugs are. "As modern medical practitioners we have to be very careful drawing conclusions from one case."
Dr Singh said Fertility Associates endorsed Menevit for men because a small study in Australia showed it improved IVF results for patients who had ICSI - where the sperm is injected into the egg.
Infertility Solutions International director, naturopath and medical herbalist Brad Crouch said it was possible the supplements improved Mr Gascoigne's fertility but each person's health was unique and they might not be a solution for all men.
Vitamenz ingredients
* L-Arginine: amino acid supports sperm production
* L-Carnitine: thought to support motility
* Taurine: antioxidant, supports male fertility as well as blood pressure, circulation and mood
* Selenium: needed to properly shape sperm and maintain sperm count
* Zinc: appears to protect sperm from bacteria and damage
* Folic acid: low levels are associated with poor sperm health
* Vitamin E: antioxidant supporting sperm motility
* Vitamin C: protects sperm and its DNA
* Kiwifruit Extract: antioxidant which defends cells from stress.