Due to Denmark’s records linking all fertility treatments with all live births, it is one of the few countries in the world where such a large-scale study could be done, providing extensive enough results for researchers to make a real-life prognosis.
Using the records researchers were able to analyze 19,884 women between 2007 and 2010 as part of the study, with the team carrying out follow-ups for live births at two, three and five years.
Their results showed that after two years 57% of the women had had a baby, with 46% of conceiving by IVF when IVF was the first fertility treatment, and 34% conceiving after intrauterine insemination when IUI was the first fertility treatment.
A significant proportion (14%) also conceived spontaneously without treatment.
However although the total number of birth rates did increase cumulatively over the five-year study period — increasing from 65% after three years to 71% after five years — these rates did not increase for women who had opted for IUI treatment lasting beyond two years, the point when most women had switched to IVF. And although 16.6% of women starting treatments with IUI had had a baby after five years, pregnancy occurred after spontaneous conception not after the IUI treatment.
And as expected by the researchers, age was the greatest factor in determining success, with further research showing that at five years, total birth rates were 80% for women under 35 years, dropping to 60.5% for those aged 35-40, and 26% for those aged 40 and over.
Commenting on the significance of the results, Dr Sara Malchau of Copenhagen University Hospital, Hvidovre, Denmark, said, “Infertility patients have two key questions: what are our chances of having a baby, and when will it happen. These results help us provide realistic information based on their age and chance of natural conception.”
“Overall, chances of a live birth are good, but successful treatment takes time. Couples will often need several treatment cycles. And even though the greatest chance of conception is following treatment, there is still a reasonable chance of spontaneous conception.”