The relationship between endometrial thickness and outcome of medicated frozen embryo replacement cycles.
OBJECTIVE
To examine the relationship between endometrial thickness and outcome of medicated frozen-thawed embryo replacement (FER) cycles.


METHODS
A retrospective observational study.


METHODS
Assisted conception unit at a university hospital.


METHODS
All patients who underwent an FER cycle between 1997 and April 2006 and met the inclusion criteria.


METHODS
For endometrial preparation, a daily dose of 6 mg of oral E(2) valerate was started on menstrual day 1, and P pessaries (800 mg daily) were administrated when the endometrial thickness had reached 7 mm or more, with ET taking place 2-3 days later. The FER cycles were categorized according to endometrial thickness measurement on the day of P supplementation.


METHODS
Implantation, clinical pregnancy, ongoing pregnancy, and live birth rates.


RESULTS
In all, 768 consecutive medicated FER cycles were analyzed. The lowest pregnancy rates were associated with endometrial thickness <7 mm (n = 13) and >14 mm (n = 12; 7% in both groups). Significantly higher implantation (19% vs. 12%), clinical pregnancy (30% vs. 18%), ongoing pregnancy (27% vs. 16%), and live birth (25% vs. 14%) rates were achieved in cycles where endometrial thickness was 9-14 mm (n = 386), compared with those in which endometrial thickness was 7-8 mm (n = 357). These differences remained significant after adjusting for confounding variables (adjusted odds ratio [OR] = 1.83 [confidence interval {CI} = 1.3-2.6] for clinical pregnancy, 1.8 [CI = 1.2-2.6] for ongoing pregnancy and 1.9 [CI = 1.3-2.8] for live birth).


CONCLUSIONS
In medicated FER cycles, an endometrial thickness of 9-14 mm measured on the day of P supplementation is associated with higher implantation and pregnancy rates compared with an endometrial thickness of 7-8 mm.
El-Toukhy
Tarek
T
Assisted Conception Unit, Guy's and St. Thomas' Hospital NHS Trust, London, United Kingdom. tarekeltoukhy@hotmail.com
Coomarasamy
Arri
A
Khairy
Mohammed
M
Sunkara
Kamal
K
Seed
Paul
P
Khalaf
Yacoub
Y
Braude
Peter
P
D000328:Adult; D049109:Cell Proliferation / Q000187:drug effects*; D015925:Cryopreservation; D004334:Drug Administration Schedule; D004359:Drug Therapy, Combination; D010064:Embryo Implantation / Q000187:drug effects; D004624:Embryo Transfer; D004717:Endometrium / Q000000981:diagnostic imaging / Q000187:drug effects*; D004958:Estradiol / Q000008:administration & dosage / Q000031:analogs & derivatives; D005260:Female; D005300:Fertility Agents, Female / Q000008:administration & dosage*; D005307:Fertilization in Vitro; D006801:Humans; D007246:Infertility / Q000000981:diagnostic imaging / Q000628:therapy*; D050498:Live Birth; D016017:Odds Ratio; D011247:Pregnancy; D018873:Pregnancy Rate; D011374:Progesterone / Q000008:administration & dosage; D012189:Retrospective Studies; D013997:Time Factors; D016896:Treatment Outcome; D014463:Ultrasonography
D005300:Fertility Agents, Female; D011374:Progesterone; D004958:Estradiol