European, U.S. Fertility-Treatment Trends Diverge


COPENHAGEN — The science is the same, but when it comes to the approach, European and U.S. fertility treatments are starting to branch out in different directions.

The latest (2002) figures from the European IVF Monitoring Program, which includes data from 24 countries, show that the overall pregnancy rate per transfer for in vitro fertilization (IVF) and intracytoplasmic sperm injection is just below 30%, compared with about 35% in the United States, reported Dr. Anders Nyboe Andersen at the annual meeting of the European Society of Human Reproduction and Embryology.

But where the Europeans really differ is in their multiple birth rate—which already is significantly lower than that of the United States and is falling faster.

Of all IVF births in Europe in 2002, 1.3% were triplet births, down from 3.6% in 1997. That's in stark contrast to the U.S. rate, which currently is 3.8%, down from 7% in 1996.

But it is the rate of twins in IVF births that fertility experts focus on most. That rate stands at 23.6% in Europe, compared with 31.6% in the United States.

The widespread adoption of elective single embryo transfer (eSET) in Europe is the driving force behind the lower multiple pregnancy rate, commented Dr. Andersen, coordinator of the European IVF Monitoring Program and head of the fertility clinic at the Rigshospitalet at Copenhagen University Hospital.

Although there is a wide variation in embryo transfer policies across European countries, 70% of all European embryo transfers involved just one or two embryos in 2002. After 2003, when the Swedish government legislated further restrictions, 70% of all Swedish transfers were elective single embryo transfers, reported Dr. Karl Nygren, an ob.gyn. at Sofiahemmet Hospital in Stockholm.

In the United States in 2002, the eSET rate was 1.2%, up from 0.8% the year before, according to Eric S. Surrey, M.D., president of the Society for Assisted Reproductive Technology (SART).

Recent guidelines released by the American Society for Reproductive Medicine, of which SART is an affiliate, suggest that priority for eSET should be given to patients with “the most favorable prognosis” (Fertil. Steril. 2004;82:773–4), and it is important to consider that the most recent eSET figures predate the new guidelines, Dr. Surrey told this newspaper.

“Any impact of this recommendation would not be seen until the 2005 outcome data,” he said. At the meeting, when Dr. Andersen was asked why IVF birth rates remain consistently higher in the United States than in Europe, he said that it is too easy to focus exclusively on the fact that Americans transfer more embryos.

“We have to face the fact that they are doing a pretty good job,” he told delegates at the meeting.

A key advantage to the U.S. approach is the trend toward smaller and more highly specialized clinics, where doctors can take a lot of time with each patient. “Perhaps Europe could learn from the United States in this regard,” he said.

ICSI Procedures Rise in Europe

For the first time in Europe, the number of intracytoplasmic sperm injection cycles exceeded regular IVF cycles; ICSI was used in 52% of all IVF cycles in 2002.

This is similar to the U.S. situation in which ICSI is used in 53% of cycles.

There are probably many reasons for the shift. “One of them could be that the relative causes of infertility are shifting,” Dr. Andersen said.

There are now fewer severe tubal problems because of better protection against STDs, while there is growing evidence male subfertility may be increasing as a result of environmental pollutants, he said. Also, many couples who previously might have used artificial insemination with donor sperm are now opting for ICSI.

Finally, since the procedure was first introduced in 1992, clinics have become more familiar and more skilled at performing it, thus making it more widely available.

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