Abstracts

Rationale: We aimed to investigate trend in birth rate and Caesarean Section (CS) rate in women with epilepsy (WWE) over time, compared to general women in the world’s lowest fertility country, south Korea. And we tried to analyze the epilepsy-related factors related to delivery by CS in WWE.


Methods: We conducted a nationwide population-based retrospective cohort study using the Korean National Health Insurance Service (NHIS) database from 2002 to 2019. Our cohort included all WWE and all pregnancies resulting in live birth in WWE, for each year. We calculated total fertility rate (TFR) for each year from 2004 to 2019 in WWE. In WWE and whole Korean women, the annual trends of childbirth and CS rates over time were assessed using a Poisson regression model and expressed as average annual percent change (AAPC), which was calculated by exponentiating the coefficient of the regression. To try to explain the higher CS rate in WWE, a logistic regression was fitted to the relationship between the CS rate and epilepsy-related variables of WWE.


Results: The TFR of WWE in 2019 is 0.3, which is about one-third of the TFR of all Korean women in South Korea (0.9). Among WWE aged 15 to 49 years, the proportion of childbirth each year decreased from 1.1% in 2004 to 0.9% in 2019 (AAPC = -3.5%; p < 0.001), showing more prominent decreasing trend than entire Korean women (AAPC = -1.3%; p < 0.001). Over the period 2004–2019, there were 2,081 CSs carried out in 4,068 pregnancies of WWE and 2,627,965 in 6,762,924 pregnancies in the whole nation (51.2% versus 38.9%, R.R.=1.32; 95% C.I. 1.28, 1.36). The proportion of CS increased from 27.3% in 2004 to 59.1% in 2019 (AAPC = 2.2%; p < 0.001) among WWE. In whole Korean women, the proportion of CS increased from 37.7% in 2004 to 50.5% in 2019 (AAPC = 1.8%; p < 0.001). When adjusted for age, residence, Obstetric Comorbidity Index and maternal disease, a greater number of anti-seizure medicine (ASM) (OR 1.74 [1.06 to 2.87] for 4 or more ASM tried during pregnancy), Epilepsy-Specific Comorbidity Index (ESCI) (OR 1.45 [1.05 to 2.01] for 2 or more ESCI) and emergency room (ER) visits because of epilepsy or seizure (OR 5.64 [2.83 to 11.24] for once or more visits during pregnancy) increased the risk of CS delivery.


Conclusions: This study presented the extremely lower TFR and higher CS rates in WWE compared with entire Korean women. The annual decreasing trend of birth rate and annual increasing trend of CS were more prominent in WWE than entire Korean women. ASMs during pregnancy and epilepsy severity were associated with CS delivery; however, the higher CS rates in WWE even under monotherapy or the absence of ER visits suggests that there may have been many unnecessary CS deliveries in WWE. Our results can be used as a large-scale, real-world-based epidemiological study data on pregnancy, childbirth, and parenting in WWE in Korea.


Funding: This work was supported by the National Research Foundation of Korea {NRF} grant funded by the Korea government {MSIT} (No. 2022R1G1A1007221).