Uterine Contractions and Mode of Progesterone in Frozen Embryo Transfer (FET) Cycles: Randomized Clinical Trial
Status:
Unknown status
Trial end date:
2015-03-01
Target enrollment:
Participant gender:
Summary
When patients undergo in vitro fertilization (IVF), they often make more embryos than it is
safe to transfer back in the womb all at once. These excess embryos are frozen and stored for
future use. Frozen embryo transfer (FET) is therefore an important option of IVF where there
are extra embryos. FET should take place under ideal conditions when uterine receptivity and
uterine endometrial lining thickness are at the appropriate developmental stage as the
embryo. A common way of preparing the uterus for FET is by using medications (Estrogen and
Progesterone) that imitate a normal menstrual cycle while monitoring the endometrial lining
development by transvaginal ultrasound. Progesterone (P4) may be administered vaginally or
intra-muscularly (IM). The mode of Progesterone administration is based upon local
conventions, experts' opinion and patients' preferences. All the mentioned modalities are
common in the daily practice of IVF clinics across the world.
The current medical literature does not present high quality evidence for the superiority of
one form of Progesterone administration over the other for FET. The investigators know that
in fresh embryo transfer cycles where natural follicles continue to function and produce
Progesterone as corpora lutea, there were no reported differences in pregnancy rates when
luteal vaginal P4 was compared with IM P4 support, but the investigators do not have the same
reassurance regarding frozen embryo transfers. The aim of this study is to compare vaginal
versus IM route of administration of P4 for FET cycle in a well-designed trial. Since many
outcome variables are possible, the investigators have chosen to concentrate in the one that
might shed light on a possible biological difference between the two modes of Progesterone
administration; uterine contractions. Uterine contractions have been previously recognized as
a possible factor that compromises success rates in patients undergoing IVF treatments.
Progesterone is considered a uterine relaxant and its levels in the blood versus the levels
in the uterus differ by its mode of administration: blood levels are higher when given IM
whereas uterine P4 concentrations are higher when given vaginally. The investigators are
interested to see whether IM progesterone in frozen embryo transfers presents a different
uterine contraction pattern than the vaginal administration.
Phase:
N/A
Details
Lead Sponsor:
Toronto Centre for Advanced Reproductive Technology