Part of the process of in vitro fertilization involves the transfer of embryos conceived in a “test tube” to the woman’s womb. Following embryo transfer, she may be confined to bed rest for 1 hour or 24 hours - but with either one the pregnancy rate seems to be similar, new research shows.

Which of these approaches - termed the mobilization and rest protocols - provides better outcomes has been uncertain, according to the report in the medical journal BJOG: an International Journal of Obstetrics and Gynaecology.

The present study involved 378 women who were undergoing IVF and were randomly assigned to rest for either 1 or 24 hours following embryo transfer. The study was conducted by Dr. Zouhair O. Amarin, from the Jordan University of Science and Technology in Irbid, and Dr. Basil R. Obeidat, from the Fakeeh Hospital in Jeddah, Saudi Arabia.

As noted, no significant difference was seen between the groups in the clinical pregnancy rate. The 1-hour rest group had a rate of 21.5 percent, whereas the 24-hour rest group had a rate of 18.2 percent, the researchers found.

In contrast, the implantation rate per embryo in the 1-hour rest group was 14.4 percent, considerably higher than the rate seen in the 24-hour rest group - 9 percent.

“Although bed rest has been advised since the first days of IVF, it is not a routine part of IVF treatment in most western clinics and there is no scientific evidence to validate this practice,” the team concludes.

SOURCE: BJOG, November 2004.