Endometrial Thickness and Endometrial Patterns as Predictors of First Trimester Spontaneous Abortion (SpAb) in Pregnancies Achieved Through Intra-Uterine Insemination (IUI)

Abstract

Objective: To assess whether endometrial thickness and or endometrial patterns on day of hCG injection is predictive of SpAb during the first trimester in pregnancies achieved with IUI.Design: A retrospective chart review of all IUI pregnancies from 1998 through 1999. Excluded were ectopic pregnancies and chemical pregnancies with hCG levels less than 50 mIU/ml.Materials and Methods: Measurement of endometrial thickness in millimeters and assessment of endometrial pattern categorized as hypoechoic, echoic, or hyperechoic in relation to the myometrium via transvaginal ultrasound on day of hCG administration.Results: Of the sixty-five pregnancies reviewed, fourteen were SpAb’s (22%) during the first trimester. The SpAb group had endometrial thickness ranging from 7 mm–14 mm; the mean thickness was 10 mm ± 3.8. (P=0.5). Seven of the fourteen SpAb’s were attributed to genetic abnormalities confirmed by genetic karyotype on the products of conception; the remaining seven SpAb’s had no identifiable cause. Five of the seven SpAb’s (71%) that did not have evidence of genetic abnormalities had a hyperechoic pattern of the endometrial lining in comparison to the myometrium. Fifty-one pregnancies were carried successfully through the first trimester. The pregnancy group endometrial thickness ranged 4 mm–15 mm; the mean was 9 mm ± 3.22 (P=0.5). Six of the fifty-one (12%) successful pregnancies had hyperechoic endometrial patterns, and three (6%) had echoic endometrial patterns. The remaining forty-two (82%) had hypoechoic endometrial patterns.Conclusion: Once pregnancy was achieved, the endometrial thickness on day of HCG administration had no predictive value for determining a successful first trimester pregnancy outcome. Although genetic abnormalities account for 50% of SpAb’s in this retrospective study, endometrial patterns may be predictive in assessing the risk of SpAb in first trimester pregnancies. Objective: To assess whether endometrial thickness and or endometrial patterns on day of hCG injection is predictive of SpAb during the first trimester in pregnancies achieved with IUI. Design: A retrospective chart review of all IUI pregnancies from 1998 through 1999. Excluded were ectopic pregnancies and chemical pregnancies with hCG levels less than 50 mIU/ml. Materials and Methods: Measurement of endometrial thickness in millimeters and assessment of endometrial pattern categorized as hypoechoic, echoic, or hyperechoic in relation to the myometrium via transvaginal ultrasound on day of hCG administration. Results: Of the sixty-five pregnancies reviewed, fourteen were SpAb’s (22%) during the first trimester. The SpAb group had endometrial thickness ranging from 7 mm–14 mm; the mean thickness was 10 mm ± 3.8. (P=0.5). Seven of the fourteen SpAb’s were attributed to genetic abnormalities confirmed by genetic karyotype on the products of conception; the remaining seven SpAb’s had no identifiable cause. Five of the seven SpAb’s (71%) that did not have evidence of genetic abnormalities had a hyperechoic pattern of the endometrial lining in comparison to the myometrium. Fifty-one pregnancies were carried successfully through the first trimester. The pregnancy group endometrial thickness ranged 4 mm–15 mm; the mean was 9 mm ± 3.22 (P=0.5). Six of the fifty-one (12%) successful pregnancies had hyperechoic endometrial patterns, and three (6%) had echoic endometrial patterns. The remaining forty-two (82%) had hypoechoic endometrial patterns. Conclusion: Once pregnancy was achieved, the endometrial thickness on day of HCG administration had no predictive value for determining a successful first trimester pregnancy outcome. Although genetic abnormalities account for 50% of SpAb’s in this retrospective study, endometrial patterns may be predictive in assessing the risk of SpAb in first trimester pregnancies.