Data Analyses
Clinical pregnancies were confirmed by the presence of a fetal heartbeat
on ultrasound scanning 7 weeks after insemination. Miscarriage was
defined as loss of a clinical pregnancy before the 28th week of
gestation. Live birth was defined as delivery of a live neonate after 28
weeks’ gestation. Our primary outcome measure was live birth rate. Our
secondary outcomes included clinical pregnancy rate and miscarriage
rate. In light of the significant differences detected related to
intrauterine insemination number between the hCG group and the urinary
LH groups , a subgroup analysis was performed to assess the impacts of
one vs. two inseminations in a given cycle for both the hCG and urinary
LH groups.
Statistical analysis was performed using SPSS Statistics 20.0 (IBM).
Mean values and standard deviations were calculated for each continuous
variable, whereas percentages were determined for the categorical
variables. Continuous variables were compared with Student’st -tests. Categorical variables were compared with chi-squared and
Fisher’s exact tests. A single, multivariate logistic regression
analysis (incorporating ovulation timing method as a categorical
explanatory variable) was performed to assess the independent effect of
hCG administration on reproductive outcomes after adjustment for
possible confounding factors, including maternal age, BMI, number of
intrauterine insemination events, and basal hormone levels (FSH, LH,
estradiol, AMH). A P value <0.05 was considered
statistically significant.