Retained placenta is associated with pre-eclampsia, stillbirth, giving birth to a small-for-gestational-age infant, and spontaneous preterm birth : a national register-based study

• ObjectiveTo evaluate whether defective placentation disorders, i.e. pre-eclampsia, stillbirth, small for gestational age (SGA), and spontaneous preterm birth, are associated with risk of retained placenta. DesignPopulation-based cohort study. SettingSweden. PopulationPrimiparous women in Sweden with singleton vaginal deliveries between 1997 and 2009 at 32-41weeks of gestation (n=386607), without placental abruption or infants with congenital malformations. MethodsRisks were calculated as odds ratios (ORs) by unconditional logistic regression with 95% confidence intervals (95%CIs) after adjustments for maternal, delivery, and infant characteristics. Main outcome measureRetained placenta, defined by the presence of both a diagnostic code (of retained placenta) and a procedure code (for the manual removal of the placenta). ResultsThe overall rate of retained placenta was 2.17%. The risk of retained placenta was increased for women with pre-eclampsia (adjusted OR, aOR, 1.37, 95%CI 1.21-1.54), stillbirth (aOR1.71, 95%CI 1.28-2.29), SGA birth (aOR1.47, 95%CI 1.28-1.70), and spontaneous preterm birth (32-34weeks of gestation, aOR2.35, 95%CI 1.97-2.81; 35-36weeks of gestation, aOR1.55, 95%CI 1.37-1.75). The risk was further increased for women with preterm pre-eclampsia (aOR1.69, 95%CI 1.25-2.28) and preterm SGA birth (aOR2.19, 95%CI 1.42-3.38). There was no association between preterm stillbirth (aOR1.10, 95%CI 0.63-1.92) and retained placenta, but the exposed group comprised only 15 cases. ConclusionsDefective placentation disorders are associated with an increased risk of retained placenta. Whether these relationships indicate a common pathophysiology remains to be investigated.

Ämnesord

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Reproduktionsmedicin och gynekologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Obstetrics, Gynaecology and Reproductive Medicine (hsv//eng)

Nyckelord

Postpartum haemorrhage

pre-eclampsia

preterm birth

retained placenta

small for gestational age

stillbirth

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)