The study compared the cost and efficacy of mild IVF treatment including single embryo transfer with a standard treatment and double embryo transfer. It included 404 women of normal weight aged 38 or younger who were referred for IVF on the basis of tubal, male or unexplained infertility.
Half the women were given mild IVF, which involved mild ovarian stimulation with gonadotropin-releasing hormone (GnRH) antagonist co-treatment and single embryo transfer.
The other group were given standard IVF.
This included standard ovarian stimulation with GnRH agonist co-treatment and double embryo transfer.
The live birth rate after one year was equivalent in the two groups - 43.4 per cent in the mild group and 44.7 per cent in the standard group.
But the rate of multiple births was much lower in the mild treatment group at just 0.5 per cent, compared to 13.1 per cent in the standard treatment group.
There were just six pre-term births in the mild treatment group, compared to 16 in the standard treatment group.
The average medical costs during pregnancy and the neonatal period were twice as high in the standard treatment as the mild group.