A long amount of bed rest following embryo transfer in assisted reproductive procedures isn't necessary, according to two doctors in a new international study.1
Long Bed Rest May be Detrimental
Zouhair Amarin, MD, of the Jordan University of Science and Technology in Irbid, and Basil Obeidat, MD, of Fakeeh Hospital in Jeddah, Saudi Arabia followed 378 women who were undergoing in-vitro fertilization (IVF). Each woman underwent controlled ovarian hyperstimulation as part of a protocol for egg retrieval, followed by IVF and subsequent embryo transfer.
But following the transfer, the women were assigned at random to undergo 1 hour or 24 hours of bed rest afterwards.
As part of the process of in-vitro fertilization, doctors first gave two hormonal medications (gonadotropins): one to control the time of ovulation, and the second to stimulate egg production. Once the patient's follicles are mature and ready to release an egg, the doctor gives a third hormone drug, a human chorionic gonadotropin (hCG), to trigger ovulation.
Just prior to the eggs' release, they are aspirated through a needle into a test tube. The eggs are then mixed or injected with the male partner's sperm. Following fertilization, a resulting embryo is transferred to the uterus to begin a pregnancy.2 Doctors may then prescribe bed rest for the patient.
Bed Rest's Effect on IVF Outcome
To determine whether a long amount of bed rest makes a difference in pregnancy success, Amarin and Obeidat compared pregnancy rates between women who were confined to bed rest for 1 hour with those who had bed rest for 24 hours. They also compared embryo implantation rates between the 2 groups of women.
"The clinical pregnancy rates were 21.5% for the 1-hour and 18.2% for the 24-hour post-embryo transfer groups," the two researchers wrote. That wasn't much of a difference.
However, they found significant differences when they looked at embryo implantation. "The implantation rate per embryo was significantly higher in the 1-hour group (14.4%) than in the 24-hour group (9%)," Amarin and Obeidat noted.
Thus, the two concluded that longer bed rest for women undergoing IVF is not necessary, and may be detrimental to embryo implantation success. "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," they wrote.
Other Physicians Concur
Doctors elsewhere have reached similar conclusions. In a much smaller study from Czechoslovakia, physicians at Charles University Prague and General Hospital in Prague evaluated the effect of bed rest involving 38 women undergoing IVF.3
Patients in the study were selected at random to have no bed rest and return home immediately after embryo transfer, or to have bed rest in a hospital overnight. Both groups of women were comparable in age, number of previous IVF attempts, the ovulation induction protocol used, the physician performing the embryo transfer, the number of transferred embryos, and the age of the embryos on the day of transfer. This was done to ensure that no other factors biased the outcomes.
The physicians found that the pregnancy rate, implantation rate, and the so-called "take home baby rate" were higher for those who received no bed rest after embryo transfer compared to those who had bed rest overnight.
The implantation rate for those with no bed rest was about 22% versus 14.5% for those with bed rest. The pregnancy rate was 50% for those with no bed rest versus about 22% for those who rested overnight. Finally, the researchers found that the take-home baby rate was 40% for those with no bed rest versus 11% for those who had bed rest overnight.
"The overnight bed rest in the hospital following embryo transfer did not ameliorate results of IVF," the Czech researchers concluded. "There is a strong tendency to [a] negative effect of bed rest."
1. Amarin ZO, Obeidat BR. Bed rest versus free mobilization following embryo transfer: a prospective randomized study. BJOG 2004 Nov;111(11):1273-6.
2. Idaho Center for Reproductive Medicine. IVF Cycle. Available at: http://www.idahofertility.com/education/ivf_cycle.html. Accessed November 30, 2004.
3. Rezabek K, Koryntova D, Zivny J. Does bedrest after embryo transfer cause a worse outcome in in vitro fertilization? [Translated from Czech]. Ceska Gynekol 2001 May;66(3):175-8.
John Martin is a long-time health journalist and an editor for Priority Healthcare. His credits include coverage of health news for the website of Fox Television's The Health Network, and articles for the New York Post and other consumer and trade publications.