Just one in three women gives birth after a single IVF attempt, but the cumulative chance of a live birth increases with each cycle - where women are offered three cycles nearly two thirds go on to have babies, reveals a thesis from the Sahlgrenska Academy at the University of Gothenburg in Sweden.
Around three per cent of all children born in Sweden are test-tube babies resulting from IVF (in vitro fertilisation).
"There are considerable discrepancies between the number of cycles offered by the various regional councils," says physician Catharina Olivius, author of the thesis. "Some councils, primarily in northern Sweden , offer just one free attempt, but this study shows that a couple's chances of having a baby increase considerably over three cycles."
The study followed almost a thousand women during their IVF treatment at Sahlgrenska University Hospital . The probability of having a baby was 35 per cent after one treatment, 52 per cent after two treatments and 63 per cent after three treatments. It was slightly higher for women under the age of 35.
Half of the couples who did not have a baby dropped out of IVF before three attempts. The most common reasons were that the treatment was felt to be too psychologically stressful, and that the chances of having a baby were considered to be very slim.
"My conclusion is that we need to get better at looking after patients' mental welfare during treatment," says Olivius. "A greater sense of wellbeing among patients would not only benefit them psychologically, but could also mean that fewer abandon treatment, which in turn could result in more couples having babies."
The risk of having twins means that these days a single fertilised egg is generally implanted in the woman's womb. A follow-up study of a previous controlled trial where 661 women were randomly assigned the implantation of one or two embryos looked at the overall birth rate after all the frozen embryos had been used. The follow-up study shows that the single-embryo transfer method results in almost as high a chance of having a baby as the double-embryo transfer method, if we include the birth rate from the frozen embryos. 44 per cent of women had a baby in the single-embryo group, and 51 per cent in the double embryo group.
"Just over a quarter of the women in the double-embryo group had twins, which was unusual in the other group," says Olivius. "Multiple pregnancies increase the risk of premature delivery, which can result in complications. Given that the results from the single-embryo transfer are almost as good, this is, in most cases, a better method."
HUGE REGIONAL DIFFERENCES
Women in Sweden are offered one, two or three free IVF treatments, depending on where they live. Three free cycles are offered in Uppsala , Stockholm , Sörmland, Kronoberg, Blekinge, Skľne, Halland, Västra Götaland, Värmland, Örebro, Västmanland, Dalarna, Gävleborg and Gotland . Two are offered in Östergötland, Jönköping and Kalmar , and just one is offered in Västernorrland, Jämtland, Västerbotten and Norrbotten (source: The Swedish Association of Local Authorities and Regions).
Source: University of Gothenburg
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