Relationship of endometrial thickness and pattern to fecundity in ovulation induction cycles: effect of clomiphene citrate alone and with human menopausal gonadotropin.

OBJECTIVE

To determine if preovulation endometrial thickness or pattern are related to fecundity and to use of clomiphene citrate (CC) or hMG in IUI.

DESIGN

Prospective ultrasound evaluation the day of hCG after CC alone (n = 197), hMG alone (n = 49), concurrent hMG or sequential CC and hMG (n = 205), and no medications (n = 23).

SETTING

Private fertility clinic.

PATIENTS

Two hundred seventy-one patients undergoing 474 cycles of IUI.

MAIN OUTCOME MEASURES

Endometrial thickness, pattern, per cycle fecundity, and continuing pregnancy.

RESULTS

Endometrial thickness was related to fecundity and continuing pregnancy. No pregnancies occurred when thickness was < 6 mm. The continuing pregnancy rate was 12.6% when thickness was > or = 9 mm, compared with 6.9% when thickness was 6 mm to 8 mm. Endometrial pattern was unrelated to pregnancy. Average endometrial thickness was decreased when hMG and CC were used in combination (7.9 mm) compared with hMG alone (9.4 mm). Endometrial thickness was negatively related to CC dose and positively related to the day of hCG administration by ANOVA.

CONCLUSIONS

Endometrial thickness the day of hCG administration is prognostic of fecundity and continuing pregnancy in cycles of ovulation induction.