Hum. Reprod. Advance Access originally published online on February 8, 2007
Human Reproduction 2007 22(5):1495; doi:10.1093/humrep/dem004
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Letters to the Editor |
Is twin pregnancy necessarily an adverse outcome of assisted reproductive technologies?
Service de Gynécologie obstétrique et Reproduction Humaine, Centre hospitalier Intercommunal site de Sèvres, 141 grande rue, 92 318 Sèvres cedex, France
E-mail: joelle.belaisch-allart{at}chi-sevres.fr
We want to thank van Wely et al. (2006) for daring to publish what many physicians believe privately, but are unwilling to express publicly, concerning twin pregnancy. Single embryo transfer, currently dominating medical journals (Gleicher, 2006), has become the dominant way of thinking. Twin pregnancies are demonized and are now considered an adverse effect of reproductive technology.
We used the French IVF register, FIVNAT and the AUDIPOG (2004) (Association of Users of Computerized Files in Perinatology, Obstetrics and Gynecology) database to compare the outcome of IVF/ICSI twins with that of twin pregnancies in the general populaton in France. AUDIPOG was created in 1994, and the network pools data from 
100 voluntary maternity units. AUDIPOG registered 180 000 births between 1994 and 2003, including 78 287 births for the 2002 and 2003 period. The standardization method makes it possible to validate estimates at a national level.
From 1986 to 2002, 16 618 twin babies were reported to FIVNAT (Belaisch-Allart et al., 2005). The mean length of gestation was 36.74 weeks. The mean weight at birth was 2413 g and the mean height was 46 cm. The percentage of premature twins born before 28 weeks of amenorrhoea was 1.17% and before 33 weeks of amenorrhoea was 7.78%. IVF twins weighed 120 g more than AUDIPOG twins. The proportion of very premature twins (<33 weeks of amenorrhoea) was 7.8% for IVF and 14% for AUDIPOG. Importantly, most complications of twin pregnancies are due to prematurity.
The average age of mothers of twins is younger in IVF than that of mothers in spontaneous twin pregnancy. Mothers of IVF twins are also very compliant with medical counselling and agree to rest whenever doctors ask. Many infertile patients prefer to conceive twins, despite the fact that they are aware of the risk to both mother and babies.
The aim of infertility treatment is to conceive a healthy baby; although the medical risks of twin pregnancies should not be underestimated, the demonization of twin pregnancy, which has been propagated by many authorities, is excessive. Banning stimulation from all intra-uterine cycles and using elective single embryo transfer prevents twin pregnancies; however, it also reduces pregnancy rates when applied to all patients (Van Montfoort et al., 2006). We applaud van Wely et al. (2006) for their courage.
References
. (2002-2003) La santé périnatale en. Gyn Obstet Fertil 32:11–22 AUDIPOG (2004).
Belaisch-Allart J, de Mouzon J, Pouly JL, Ayel JP. (2005) Grossesses gémellaires après AMP. FIVNAT. Gynecol Obstet Fertil 33:602–604.[CrossRef][Medline]
Gleicher N and Barad D. (2006) The relative myth of elective single embryo transfer. Hum Reprod 21:1337–1344.
van Wely W, Twisk M, Mol B, van der Veen F. (2006) Is twin pregnancy necessarily an adverse outcome of assisted reproductive technologies? Hum Reprod 21:2736–2738.
van Montfoort AP, Fiddelers AA, Janssen JM, Derhaag JG, Dirksen CD, Dunselman GA, Land JA, Geraedts JA, Evers JL, Dumoulin JC. (2006) In unselect patients, elective single embryo transfer prevents all multiples, but results in significantly lower pregnancy rates compared with double embryo transfer: a randomized controlled trial. Hum Reprod 21:338–343.
CiteULike 
Connotea 
Del.icio.us What's this?
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||