Factors influencing pregnancy rates in intrauterine insemination

Kim, Yeon Kyoung; Shin, Dong Myung; Kim, Do Gyun; Yang, Hoe Saeng

Abstract

OBJECTIVE
We have studied the factors that influence the pregnancy rate in ovarian hyperstimulation and intrauterine insemination (IUI) in infertility patients.
METHODS
Seventy two patients who visited the infertility clinic in Dongguk University Kyong-ju hospital from January 2002 to December 2003 underwent IUI after 99 cycles of ovarian hyperstimulation. We administered clomiphene with exogenous gonadotropin from cycle day 3 and then IUI was performed. The variables selected for retrospective analysis were patient's age (<35 years), duration (<6 years) and type (primary or secondary) and etiology of infertility, number of treatment cycles (>or=2), number of follicles (>or=2), size of dominant follicle (>or=18 mm), total sperm counts (>or=10 X 10(6)). Chi-square test, Fisher's exact test and a multiple logistic regression analysis were used to detect differences between groups in each variable.
RESULTS
The pregnancy rate per patient was 29.2% (21/72) and 21.2% (21/99) per cycle. Factors that influenced pregnancy rate were age, number of treatment cycles, number of preovulatory follicles (>or=16 mm), and total inseminated motile sperm counts, all of which showed significant differences (p<0.05). Multiple logistic regression analysis identified significant predictors as age (<35 vs. >or=35), number of treatment cycles (2 cycle vs. 1 cycle), number of preovulatory follicles (>or=16 mm) (>or=3 vs. 1), and total inseminated motile sperm counts (>or=40 X 10(6) vs. <10 X 10(6)). The odds ratio of each of these variables were 12.6, 3.37, 11.64, and 10.59.
CONCLUSION
For successful pregnancy rates in IUI after ovarian hyperstimulation, the patient's age, number of treatment cycles, number of preovulatory follicles, and total inseminated motile sperm counts should be considered.