The purpose of this work was to measure the effect of the proper prenatal medical care on the health of newborns. This study was based on a survey conducted in France in 2010 by the National Institute for Health and Medical Research and the Ministry of Health. Three different definitions of newborn health were used, and the definition of proper prenatal care was set based on the recommendations of the Haute Autorité de Santé (HAS). The analysis was conducted based on propensity score methods to adjust for potential confounders. The results showed that proper prenatal may reduce some newborn health problems. But, if allowance is made for women’s behaviour or for mothers’ perceptions of their pregnancy, prenatal care could have no effect on newborn health. Moreover, it seems that a subpopulation of women would use prenatal care visits to enforce a self-commitment, to adhere to personal good conduct rather than for only medical reasons. Better information, prevention and customization of prenatal care according to pregnant women’s profiles might be more effective in terms of health and perhaps cost-saving.