Results
Table 1 shows the baseline characteristics. We identified 41,546 cycles
who met the study criteria, including 1590 women with elementary school
graduate or less, 10996 women with middle graduate, 8354 with high
school graduate, and 20606 with college graduate or higher. The
distribution of baseline characteristics of the study population is
presented in Table 1. There was a significant difference in baseline
characteristics between groups, with elementary school or less education
level women more likely to be older, have longer infertility duration,
higher BMI, more secondary infertility, IVF insemination, fresh embryo
transfer, and double embryo transfer, while less no. of oocyte retrieved
and agonist protocol in the fresh cycle. The live birth rate,
miscarriage rate, and clinical pregnancy rate in elementary school
graduate or less were lower compared to other groups.
Univariate analysis was performed to evaluate each variable’s effect on
the live birth rate (Table 2). Female age, infertility duration, BMI,
secondary infertility, antagonist, and other protocol in the fresh cycle
and frozen embryo transfer were negatively associated with live birth,
while endometrial thickness, no. of oocyte retrieved, and double embryo
transfer were positively associated with live birth. Interaction and
stratified analyses were shown in Table S1. There were no significant
interactions in any of the subgroups (p>0.05 for all
comparisons).
Compared with women with an education corresponding to elementary school
graduate or less, there was an increased rate of live birth among women
with higher educational levels in the crude model. However, after
adjusting for female age, infertility duration, BMI, EM thickness, no.
of oocyte retrieved, infertility type, protocol in the fresh cycle,
fertilization type, time of transfer, and no. of embryo transferred,
women’s educational level was not associated with live birth.