CESAREAN-SECTION IN TWIN PREGNANCIES IN 2 DANISH COUNTIES WITH DIFFERENT CESAREAN-SECTION RATES

Objective. Based on a comparison of the clinical indications for cesar ean section (CS) in two Danish counties and a review of the literature regarding this issue the aim of this study was to discuss possible ex planations for variations in CS rates in twin pregnancies. The compari son of indications for CS in twin pregnancies was made between two Dan ish counties, one with a high. and one with a low overall CS rate in t win deliveries, taking into account the distribution of parity, mother 's age, gestational age at birth, and birth weight. Design. A populati on based, historic follow-up study based on antecedent data.Setting. T wo Danish counties, with a CS rate in twin pregnancies of 57% and 28%, respectively. Subjects. All women with twin pregnancies who delivered in 1989 in the two counties. Main outcome measures. Comparison of the CS rates in the two counties according to indications and fetal prese ntation. Secondary measures. Perinatal and maternal outcome. Results. The difference in CS rates between the two counties could not be expla ined by different distributions of background characteristics. Differe nt attitudes were found towards CS in cases with previous CS, with twi n A in breech presentation and in cases with vertex-breech deliveries. These differences could explain less than two thirds of the overall 2 9% (CI: 12-46%) difference in risk of CS between the two counties, ind icating more subtle reasons for the discrepancy. No difference between the two counties in perinatal morbidity and mortality was seen. Concl usion. In order to understand and discuss regional variations in the u se of CSs in twin deliveries the subjects must be addressed in differe nt ways: the unequivocal indications related to fetal presentations an d previous CS can be subjected to randomised controlled trials or larg e scaled follow-up studies regarding maternal and perinatal morbidity and mortality. Other more subtle determinants of the physicians' and t he pregnant women's attitude towards CS, however, seem quantitatively important, and these can only be evaluated in observational studies an d through discussions.