Open AccessFetal death and placental weight/birthweight ratio: a population study
Author(s) -
Haavaldsen Camilla,
Samuelsen Sven O.,
Eskild Anne
Publication year - 2013
Publication title -
acta obstetricia et gynecologica scandinavica
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.401
H-Index - 102
eISSN - 1600-0412
pISSN - 0001-6349
DOI - 10.1111/aogs.12105
Subject(s) - medicine , odds ratio , obstetrics , quartile , confidence interval , birth weight , population , small for gestational age , gestational age , pregnancy , fetus , relative risk , biology , environmental health , genetics
Abstract Objective To study the association of placental weight and placental weight/birthweight ratio with gestational age‐specific fetal death. Design Population‐based study. Setting Medical Birth Registry of Norway. Population All singleton births in Norway, 1999–2008 ( n = 534 892). Methods Gestational age‐specific quartiles of placental weight and placental weight/birthweight ratio were estimated, and proportions of fetal deaths and live births within the lowest and highest quartile were compared. The risk of fetal death associated with placental weight/birthweight ratio was estimated as crude and adjusted odds ratios. Main outcome measures Offspring vital status. Results Pregnancies with fetal death were overrepresented in the lowest quartile of placental weight and placental weight/birthweight ratio in term and preterm deliveries. In preterm deliveries, fetal deaths were also overrepresented in the highest placental weight/birthweight ratio. Adjusted odds ratio of fetal death in preterm deliveries was 1.67 (95% confidence interval 1.44–1.94) for placental weight/birthweight ratio in the lowest quartile and 1.79 (95% confidence interval 1.55–2.08) in the highest quartile. Corresponding odds ratios for deliveries at term were 1.76 (95% confidence interval 1.50–2.06) and 1.18 (95% confidence interval 0.99–1.41). Conclusions Both small and large placentas relative to birthweight were associated with fetal death in preterm births. At term, only small placentas relative to birthweight were associated with fetal death. Understanding the mechanisms behind the increased risk of adverse pregnancy outcomes in pregnancies with disproportionate placental weight/birthweight ratio may be important for prevention of fetal deaths.