Fetal outcomes
Fetal outcomes are presented in Table 2. More pregnancies had a preterm birth in the unplanned-pregnancy group than in the planned-pregnancy group (20.4% vs. 3.3%; P < 0.001, Chi-square test). The cesarean section rate was higher in the unplanned group than in the planned group (56.3% vs. 45.1%; P = 0.023, Chi-square test). Compared with the unplanned-pregnancy group, the planned-pregnancy group had a significantly higher live birth rate (96.8% vs. 83.0%; P< 0.001; Chi-square test), and a lower induced abortion rate (2.7% vs. 13.5%; P < 0.001; Chi-square test). The planned-pregnancy group seemed to have less SFL than the unplanned-pregnancy group, though statistical significance was not reached (0.5% vs. 3.5%; P = 0.077, Chi-square test).
The MCM rate within one year after delivery among live births in the unplanned group was significantly higher than that in the planned-pregnancy group (7.5% vs. 1.6%; P = 0.006, Chi-square test). All the three MCM cases in the planned-pregnancy group were congenital cardiac defects, of which one was ventricular septal defect, one was patent foramen ovale, and the other one was atrial septal defect. Of the 18 MCMs in the unplanned-pregnancy group, there were nine cases with congenital cardiac defects, two cases with bifid spine, two cases with cleft lip and cleft palate, two cases with hypospadias, one case with conjoined twins, one case with club foot, and one case with anotia. Detailed AED treatment patterns and folic acid supplementation for the 21 pregnancies with MCMs in the planned and unplanned group are presented in Table S1 in the supplement. All cases of MCMs had no family history of malformation.
Next, we pooled the pregnancies with either induced abortion, SFL, preterm birth, or offspring with MCMs together and referred to them as pregnancies with adverse fetal outcomes. Regression analysis demonstrated that the risk of adverse fetal outcomes was significantly lower for the planned pregnancies when planning was entered alone (OR, 0.13; 95% CI, 0.07-0.23; P < 0.001) or adjusted for age at conception, whether taking VPA in either monotherapy or polytherapy in the first trimester, the frequency of GTCS during pregnancy, and whether receiving appropriate folic acid supplementation (OR, 0.14; 95% CI, 0.08-0.27; P < 0.001). Regression analysis also identified whether taking VPA during pregnancy (OR, 4.34; 95% CI, 2.09-9.00; P < 0.001), frequency of GTCS during pregnancy (OR, 1.16; 95% CI, 1.03-1.3; P = 0.012) but not age at conception (OR, 1.00; 95% CI, 0.94-1.07; P = 0.935), and appropriate folic acid supplementation (OR, 1.02; 95% CI, 0.63-1.66;P = 0.941) were significant independent associated factors.