ENDOMETRIAL PATTERN AND THICKNESS ASSOCIATED WITH PREGNANCY OUTCOME AFTER ASSISTED REPRODUCTION TECHNOLOGIES

The endometrial pattern and thickness was analysed prospectively on the day of administration of human chorionic gondotrophin (HCG) in 200 in-vitro fertilization (IVF), gamete intra-Fallopian transfer (GIFT) and tubal embryo transfer (TET) cycles. Increasing maturity of the endometrial pattern was positively correlated with oestradiol levels (r = 0.20; P = 0.005), number of mature eggs (r = 0.13; P < 0.05) and the number of top quality embryos (r = 0.40; P < 0.001). The endometrial thickness was positively, correlated with the number of follices greater-than-or-equal-to 15 mm (r = 0. 15; P < 0.02) and the cycle day on which HCG was administered (r = 0.14; P < 0.03). It was unaffected by the dose of human menopausal gonadotrophin and was negatively correlated with the use of clomiphene citrate (r = 0.40; P < 0.001). Fecundity was increased for IVF when the endometrial thickness was greater-than-or-equal-to mm (P < 0.05) and for GIFT and TET when a Type C triple-line endometrial pattern was present (P < 0.05). Biochemical pregnancies for the combined methods increased from 2.5% of all pregnancies when the endometrial thickness was 9-13 mm, to 27.8% when the thickness was < 9 mm or > 13 mm (P < 0. 0 1). Biochemical pregnancies occurred in 67% of IVF pregnancies when the endometrial thickness was greater-than-or-equal-to 13 mm. These findings suggest that fecundity may be increased and biochemical pregnancies may be avoided by administration of HCG when the endometrial thickness is greater-than-or-equal-to 9 mm but still less-than-or-equal-to 14 mm.