Women who previously have undergone a caesarean-section can safely attempt a vaginal birth during a subsequent pregnancy, even if they are at or past 40 weeks' gestation, according to a study published in the October issue of Obstetrics & Gynecology, Reuters reports. However, the chances of completing such a delivery successfully are slightly decreased, the study found. Kara Coassolo of the Hospital of the University of Pennsylvania-Philadelphia and colleagues examined the outcomes for 11,587 women who attempted a vaginal birth after c-section before, at and after 40 weeks' gestation. The researchers found that 69% of women who attempted VBAC at or after their estimated date of delivery were less likely to be successful compared with 78% of women who delivered before their estimated date of delivery. Doctors "can counsel women that the chances of VBAC success are decreased in gestations that continue beyond the estimated delivery date compared with those before 40 weeks," researchers said, adding, "However, patients can be reassured that the success rate of almost 70% is still quite good." Researchers said there was a small increase in "absolute risk" of operative complications and adverse effects among women who attempted VBAC at or beyond 40 weeks' gestation compared with those who chose repeat c-section delivery. However, the differences disappeared once other factors were taken into account. Therefore, the "risks of a VBAC attempt are not increased simply because the due date has passed," the researchers said (Reuters, 10/3).