Uterine contractions at the time of embryo transfer alter pregnancy rates after in-vitro fertilization.
To investigate the possible consequences of uterine contractions (UC) as visualized by ultrasound (US) on in-vitro fertilization (IVF)-embryo transfer outcome, we studied prospectively 209 infertile women undergoing 220 cycles of controlled ovarian stimulation. Inclusion criteria were age < or = 38 years, a morphologically normal uterus, and at least three good quality embryos transferred. Just before embryo transfer, women underwent 5 min digital recordings of the uterus using US image analysis software for UC assessment. Plasma progesterone and oestradiol concentrations were measured. Four groups were defined according to UC frequency: < or = 3.0 (n = 53), 3.1-4.0 (n = 50), 4.1-5.0 (n = 43), and > 5.0 (n = 74) UC/min respectively. Patients, controlled ovarian hyperstimulation and embryology characteristics were comparable in all groups. A stepwise decrease in clinical and ongoing pregnancy rates as well as in implantation rates occurred from the lowest to the highest UC frequency groups (53, 36, 21; 46, 32, 20; 23, 19, 10; and 14, 11, 4%; P < 0.001). Plasma progesterone and UC frequency were negatively correlated (r = -0.34, P < 0.001). Direction of UC did not affect embryo transfer outcome. As this study was controlled strictly for confounding variables and UC were assessed objectively by a computerized system, its results indicate that high frequency UC on the day of embryo transfer hinder IVF-embryo transfer outcome, possibly by expelling embryos out of the uterine cavity. The negative correlation between UC frequency and progesterone concentrations supports the uterine relaxing properties of progesterone.
Fanchin
R
R
Department of Obstetrics and Gynaecology and Reproductive Endocrinology, Hôpital Antoine Béclère, Clamart, France.
Righini
C
C
Olivennes
F
F
Taylor
S
S
de Ziegler
D
D
Frydman
R
R
D006063:Chorionic Gonadotropin / Q000008:administration & dosage; D004624:Embryo Transfer; D004958:Estradiol / Q000097:blood; D005260:Female; D005307:Fertilization in Vitro; D005640:Follicle Stimulating Hormone / Q000097:blood; D006801:Humans; D008596:Menotropins / Q000008:administration & dosage; D010062:Ovulation Induction; D011247:Pregnancy; D011374:Progesterone / Q000097:blood; D011446:Prospective Studies; D014463:Ultrasonography; D014590:Uterine Contraction; D014599:Uterus / Q000000981:diagnostic imaging
D006063:Chorionic Gonadotropin; D011374:Progesterone; D004958:Estradiol; D008596:Menotropins; D005640:Follicle Stimulating Hormone