All patients will be able to get a free cycle of IVF treatment on the NHS providing they meet certain criteria drawn up by experts.
Louise Brown was the first test tube baby, born in 1978 in Oldham
The treatment had previously been unavailable to people living in north, mid and west Wales.
Health Minister Brian Gibbons described the move as the end of a "postcode lottery".
Patients must meet criteria which includes slimming down if they are obese and giving up smoking.
Until now, availability of IVF (In Vitro Fertilisation) on the health service had depended on where potential patients lived.
The former North Wales Health Authority and Dyfed-Powys Health Authority stopped the service, meaning it was only available in south Wales.
The Welsh Assembly Government has now changed the access rules so that all eligible patients can qualify, wherever they live, and this means an estimated 600 couples will have the chance to start a family.
However, some people from north and mid Wales are expected to have to travel to hospitals in England for their treatment, as they are currently the closest centres with the necessary expertise.
Dr Gibbons said a failure to conceive could cause "a great deal of stress, worry and sadness."
'Better and fairer'
"The present postcode lottery made this even worse," he added.
He said the new criteria, based on expert recommendations, would "provide better and fairer access to this treatment".
"It will hopefully enable about 600 new Welsh patients to access IVF and have the chance of starting a family."
Women have to be under 40 when IVF treatment begins
Patients will have to comply with a number of rules before they are offered help including:
Treatment should start before a woman's 40th birthday, and she must be aged no more than 38-and-a-half when referred.
Couples must have no adopted or biological children living with them, and one must never have had a child.
Patients must have a body mass index (BMI) between 19-30. The BMI compares someone's height and weight, and anyone over 30 is regarded as obese. If they are outside this range they will be put on the waiting list, but must have lost weight by the time treatment starts.
If a woman or her partner smokes, they have to take part in a programme to quit, and have actually stopped by the time of treatment.
Last year, the assembly government set up a group to examine the issue after advice was published by NICE, the health guidance body for both Wales and England.
NICE recommended that the NHS should pay for three treatment cycles. Figures show about 25% of women who have one cycle of treatment become pregnant, while 50% do so after three.