Pituitary suppression in ultrasound-monitored frozen embryo replacement cycles. A randomised study.
BACKGROUND
This study was designed to assess the value of using a gonadotrophin-releasing hormone (GnRH) agonist prior to exogenous steroid supplementation for endometrial preparation in frozen-thawed embryo replacement (FER) cycles.


METHODS
A prospective randomized trial of 234 patients undergoing FER cycles was conducted. The study population was randomly divided into two groups according to a computer-generated list. In group A (n = 117), a daily dose of 6 mg of oral estradiol valerate was initiated on menstrual day 1 following pituitary suppression using 400 mcg buserelin acetate daily. In group B (n = 117), the same dose of estradiol valerate was initiated on day 1 of bleeding without prior GnRH agonist therapy. In both groups, ovulation monitoring was not undertaken and progesterone pessaries (800 mg daily) were administrated when the endometrial thickness had reached 8 mm or more with embryo transfer taking place 2 days later.


RESULTS
The two groups were comparable with respect to cause of infertility, age at stimulation (32.8 +/- 4 vs 33.2 +/- 3.9 years, P = 0.4), basal FSH level (6.3 +/- 1.7 vs 6.4 +/- 2 IU/l, P = 0.5), number of oocytes collected (16.9 +/- 7.3 vs 16.5 +/- 7.4, P = 0.7) and fertilized normally in the retrieval cycle (11.5 +/- 4.9 vs 11 +/- 4.9, P = 0.4) and number of embryos cryopreserved (6.6 +/- 3.6 vs 6.2 +/- 3.6, P = 0.3). There was no significant difference between the two groups in age at frozen replacement (33.6 +/- 4.2 vs 34 +/- 3.9 years, P = 0.4), duration of the proliferative phase (20.7 +/- 8.6 vs 21 +/- 9.2 days, P = 0.7) and number of thawed embryos replaced (2.3 +/- 0.6 vs 2.2 +/- 0.6, P = 0.2). However, compared with group B, group A achieved significantly higher pregnancy (37.6% vs 24%, OR 1.8, 95%CI 1.1-3.4), clinical pregnancy (24% vs 11.3%, OR 2.5, 95%CI 1.2-5.5) and live birth rates (20% vs 8.5%, OR 2.9, 95%CI 1.2-8).


CONCLUSIONS
Medicated frozen embryo replacement cycles timed by endometrial thickness measurement alone without monitoring or suppression of ovarian activity are associated with reduced outcome.
El-Toukhy
T
T
Assisted Conception Unit, Guy's and St. Thomas' Hospital NHS Trust, St. Thomas' School of Medicine, St. Thomas Street , London SE1 9RT, UK. tarekeltoukhy@hotmail.com
Taylor
A
A
Khalaf
Y
Y
Al-Darazi
K
K
Rowell
P
P
Seed
P
P
Braude
P
P
D000328:Adult; D001723:Birth Rate; D002064:Buserelin / Q000008:administration & dosage / Q000627:therapeutic use*; D015925:Cryopreservation; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D004624:Embryo Transfer; D004622:Embryo, Mammalian; D004717:Endometrium / Q000000981:diagnostic imaging*; D004958:Estradiol / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000627:therapeutic use; D005260:Female; D005300:Fertility Agents, Female / Q000008:administration & dosage / Q000627:therapeutic use*; D007987:Gonadotropin-Releasing Hormone / Q000819:agonists*; D006801:Humans; D010902:Pituitary Gland / Q000187:drug effects*; D011247:Pregnancy; D018873:Pregnancy Rate; D011446:Prospective Studies; D014463:Ultrasonography
D005300:Fertility Agents, Female; D007987:Gonadotropin-Releasing Hormone; D004958:Estradiol; D002064:Buserelin