ObjectiveThe use of frozen embryos in the treatment of infertility with assisted
reproductive techniques has been increased. Different methods are used to
prepare the endometrium for frozen embryo transfer (FET). The aim of this
study was to compare pregnancy outcomes after treatment with tamoxifen and
hormonal replacement therapy (HRT) in FET.MethodsThis randomized clinical trial was carried out with 214 infertile women in
the infertility research center of Milad Hospital in Mashhad during
2018-2020. We had 84 patients receiving tamoxifen and 92 took HRT.
Endometrial thickness (ET) and pregnancy outcome were measured in both
groups.ResultsMean infertility duration (p=0.328), number of embryos
(p=0.649), FSH (p=0.390), LH
(p=0.051) and LH/FSH ratio (p=0.287)
as well as type of infertility (primary or secondary)
(p=0.295), causes of infertility (p=0.750)
and pattern of menstruation (p=0.676) were not
significantly different in the two groups. Mean ET in the TMX and HRT groups
were 8.72±1.45mm and 9.00±1.69mm, respectively
(p=0.423). There was no statistically significant
difference between chemical pregnancy (p=0.663), clinical
pregnancy (p=0.994) and ongoing pregnancy
(p≥0.999) in the TMX and HRT groups.ConclusionsTreatment with tamoxifen can be as effective as GnRH agonist for endometrial
preparation in FET.