Research Article Volume 8 • Issue 4 158 Affiliation: 1 Service de Néonatologie. Centre Hospitalier Universitaire Sud Réunion, BP 350, 97448 Saint- Pierre Cedex, La Réunion, France 2 Centre d’Etudes Périnatales Océan Indien (CEPOI). Centre Hospitalier Universitaire Sud Réunion, BP 350, 97448 Saint-Pierre cedex, La reunion, France 3 Department of Obstetrics & Gynaecology, University of Adelaide, Robinson Institute. Lyell McEwin Hospital, Adelaide, Australia 4 Systems Biology of Reproduction Research Group, Institute of Enzymology, HUN-REN Research Center for Natural Sciences. Department of Obstetrics and Gynaecology, School of Medicine, Semmelweis University. Budapest, Hungary 5 Department of Obstetrics and Gynaecology, Mater Dei Hospital, Bari, 70125 Bari, Italy 6 Service de Gynécologie et Obstétrique. Centre Hospitalier Universitaire Sud Réunion, BP 350, 97448 Saint-Pierre cedex, La reunion, France *Corresponding author: Dr Pierre-Yves Robillard. Service de Néonatologie. Centre Hospitalier Universitaire Sud Reunion, BP 350, 97448 Saint-Pierre cedex, La Réunion, France. Citation: Pierre-Yves Robillard, Gustaaf Dekker, Nandor G Than, Francesco Bonsante, Malik Boukerrou, Marco Scioscia, Phuong Lien Tran, Silvia Iacobelli. Quantitative Discrimination of Small for Gestational Age (SGA) Singleton Newborns. Incidences. Risk Factors and Foetal Outcomes of the three Major Subtypes of SGA: A 23-Year Cohort of 8,601 Singleton SGA (Out of 83,917 Births). Journal of Pediatrics, Perinatology and Child Health. 8 (2024): 158-171. Received: August 30, 2024 Accepted: September 06, 2024 Published: October 03, 2024 Abstract Objectives: Quantifying the different sorts of small for gestational age (SGA): constitutional SGA vs fetal growth restriction (FGR, i.e. Doppler anomalies), and verifying if the most frequent cause of FGR is associated with maternal preeclampsia. Design: University’s maternity, 23.5 year-observational population-based cohort study. All consecutive singleton pregnancies. Main outcome Measures: Comparing risk factors between the different types of SGA’s and controls (pregnancies without preeclampsia and SGA). Results: There were 8,601 SGA/ 83,617 malformations excluded births (10.2%). Those associated with maternal preeclampsia (PES, N= 536) represented 6.2% of all SGA, those without maternal preeclampsia but diagnosed with having Doppler anomalies « vascular SGA » (VascS, N= 1,389) represented 16.1%. The remaining N= 6,676, without Doppler anomalies “constitutional SGA” (constS) comprised ¾ (77.6%) of all SGA. Singleton pregnancies without any hypertensive disease and without SGA (N= 75,316) represented the control group. Preeclamptic mothers were on average older than controls 28.5 years vs 27.9, p=0.03. VascS and constS being younger 27.3, p<0.0001. Pre-pregnancy BMI was 25.9 kg/m² in PES vs 25.0 in controls (p< 0.0001), while it was significantly lower (24.0) in VascS and constS. In multiparas, the rate of primipaternity for the index pregnancy was much higher in PES and VascS (16.5%) compared with controls (4%) and ConstS (4.7%); OR 4.8, p< 0.0001. A history of prior preeclampsia had a similar effect in VascC and ConstS: adjOR ≈ 1.5, while a history of previous SGA had a major effect (OR 4.9). The date of delivery in the constitutional SGA group was the same than controls. Conclusions.: First, 77%, of SGA (small for gestational age, 10% of all births) were constitutional with no special risk for the newborn. Severely ill SGA (FGR) represented only one quarter (23%) of all SGA. Second, but main findings: three quarters of these FGR belonged to pregnancies without any detectable maternal disease (preeclampsia). FGR associated with maternal preeclampsia comprized only one quarter of FGR. Quantitative Discrimination of Small for Gestational Age (Sga) Singleton Newborns. Incidences, Risk Factors and Foetal Outcomes of the Three Major Subtypes of Sga: A 23-Year Cohort of 8,601 Singleton Sga (Out of 83,917 Births) Pierre-Yves Robillard MD 1,2* , Gustaaf Dekker MD, PhD 3 , Nandor G Than MD, PhD 4 , Francesco Bonsante MD 1,2 , Malik Boukerrou MD, PhD 2,6 , Marco Scioscia MD, PhD 5 , Phuong Lien Tran MD 6 , Silvia Iacobelli MD, PhD 1,2 Keywords: Small for gestational age; Intrauterine growth restriction; Fetal growth restriction; Preeclampsia; Gestational weight gain