Impact of a cultural belief about ghost month on delivery mode in Taiwan

Background: Many Chinese believe the lunar month of July, "ghost month'' is inauspicious for major surgical procedures. This study hypothesised that caesaren delivery (CS) rates will be significantly lower during lunar July, and higher than normal during June, representing pre-emptive caesaren delivery to avoid delivering in July. Methods: Population based data from Taiwan on all singleton deliveries during 1997-2003 (1750862 cases) were subjected to multivariate autoregressive integrated moving average (ARIMA) modelling, adjusting for major obstetric complications (previous CS, breech presentation, dystocia, and fetal distress). Results: ARIMA intervention models showed significantly lower CS rates in lunar July, and among younger age groups (p < 0.001), but not among 35 plus aged mothers. Incidence of previous CS, is significantly higher among June deliveries, while the incidence of the remaining major complications is similar in July, June, and other months. Patients with clinically less salient obstetric complications show significantly lower CS rates in July. Conclusions: Adjusted CS rates during the ghost month are significantly lower than other months. Lunar June shows an increase in deliveries of previous CS mothers (almost all by CS), suggesting elective CS to pre-empt CS in July. A major policy implication is that health education must be launched to dissipate the cultural belief about the ghost month. Evidence also implies some proportion of clinically un-indicated CS in other months, showing the need for professional and policy initiatives to reduce unnecessary CS. Policy makers and researchers in other countries should be alert to cultural beliefs associated with delivery to enable informed delivery choices by mothers.