Length, weight and head circumference as reliable signs of maturity in a modern German birth collective

Signs of maturity such as weight, length and head circumference are still a measure used to investigate cases of suspected neonaticides as they help to differentiate between newborns born dead or alive. However, limit values for these signs have not changed for a long time. Our study considers whether limit values should have changed and which validity the current ones have. We investigated the cases of 3162 newborns, dividing them into a mature and an immature collective on the basis of the gestational week. Application of these signs of maturity (2500 g, 48 cm, 34 cm) had a high predictive value concerning maturity (>99%), and even applying only one sign of maturity gave a predictive value over 97%. Clinically the mature collective showed a slightly lower rate of ventilation (2% compared to 2.4% for the non-mature collective). Coherences between maternal age/weight and postnatal ventilation could be shown. Coherences with reanimation could not be investigated since the case number was too low. Our results show that, for valid forensic investigation, these numeric signs of maturity have to be supplemented by further investigations and other influencing factors have to be considered. Therefore, clinical instruments such as the Petrussa-Index, clavicule length measuring and foot length measuring must be considered.