projet de recherche (1) Second-born children (1) States (1) Birth (1) Registers of births, etc (1) Prenatal care (1) Pregnancy (1) Parturition (1) Parents (1) Labor (Obstetrics) (1) Home (1) Gestational age (1) Families (1) Childbirth (1) Cesarean section (1) Birth weight (1) Birth certificates (1) Spacing (1) States (1) Birth (1) Pregnancy (1) naissance (1)