A simple, inexpensive and effective artificial cycle with exogenous transdermal oestradiol and vaginal progesterone for the transfer of cryopreserved pronucleated human oocytes in women with normal cycles

Supernumerary pronucleated stage oocytes (PN) are usually cryopreserved. PN are transferred in spontaneous, stimulated or artificial cycles. In this study, an artificial cycle with a transdermal therapeutic system was used for oestradiol release (Estraderm TTS 100®) in combination with a targeted drug delivery system for vaginal progesterone release (Crinone 8%®). Patients started transdermal 17β-oestradiol treatment on cycle day 1. Only one clinical monitoring was necessary on day 14 for confirmation of satisfactory endometrial development and exclusion of ovulation by transvaginal ultrasound and endocrine determinations (oestradiol, progesterone and luteinizing hormone). Embryo transfer was performed on the third day of progesterone treatment (day 17). The first 25 cycles were recently completed in a prospective study; no cycles were cancelled due to ovulation or unsatisfactory endometrial development. In comparison with the previous protocol of embryo transfer in stimulated cycles in our clinic which required extensive ultrasound and endocrine monitoring, the pregnancy rate in these oestrogen- and progesterone-supplemented cycles was nearly twice as high (34.8%). Two pregnancies were even achieved with zygotes after microinjection of frozen-thawed late spermatids extracted from testicular tissue (cryo-TESE). In these cycles, the Estraderm TTS 100/Crinone 8%® protocol seems to be superior to stimulation protocols and even to other protocols reported so far for artificial cycles with exogenous oestradiol and progesterone treatment.