Póka R, et al. - Researchers examined the Caesarean section rate as a function of birth weight among Robson-1 parturients. In addition, they compared these rates with that among the unselected obstetric population. In an unselected obstetric population of 26,012 parturients, the 90th birth weight centile of fetuses delivered at 37, 38, 39, 40, 41, and 42 weeks gestation were 3960 g, 3960 g, 4000 g, 3950 g, 4000 g and 3820 g, respectively. Six hundred and seventy-seven fetuses weighed >4000 g, and 448 patients (66%) were delivered vaginally among Robson-1 parturients. Outcomes suggest that a valid reason could not be provided to downplay the intent of vaginal birth based on the fetal size above 3900 g that would be associated with increased odds of Caesarean delivery, even with the best possible estimation of fetal weight.