Placental Pathology in IUGR Infants: An 8 Year Overview
Jane Thorne, Paul Downey, Eoghan Mooney. National Maternity Hospital, Dublin, Ireland
Background: Infants with intrauterine growth restriction (IUGR) are at an increased risk of perinatal disease, including death. Placental disease is an important cause of IUGR, and gross and microscopic examination of the placenta is critical in explaining such cases. IUGR is variably defined as less than the 10th, 5th or 3rd centiles: use of the smaller centiles means that fewer constitutionally small but normal infants are likely to be included.
Design: Reports of placentas of infants with a birth weight <2 Standard Deviations from the mean (approx. 3rd centile) born between January 1st 2004 and December 31st 2011 were evaluated. Exclusion criteria were multiple gestation, congenital anomaly and a gestational age <24 weeks. Cases with autopsies were included. The primary pathology was determined in each case and assigned a category 1-8 as given in the table below. Where two or more pathologic findings were present, they were ranked as primary or secondary pathology in terms of severity of disease. Data for acute pathologies eg. acute chorioamnionitis was not included.
Results: There were 69,439 deliveries over the study period. 461 IUGR cases were identified. 21 were excluded as above. No placentas were available in 44 cases, leaving a study group of 396 cases. In 380 cases a full macroscopic examination with optimal sampling was available, in 16 a delivery ward sample was reviewed.
|1||Shallow implantation/ ischaemia||148 (37.4)||15|
|2||Fetal Thrombotic Vasculopathy||29 (7.3)||26|
|3a||Villitis, low grade||31 (7.8)||16|
|3b||Villitis, high grade||38 (9.6)||12|
|4||Increased Perivillous fibrin w/without intervillositis||20 (5.1)||6|
|5||Delayed maturation||62 (15.6)||13|
|6||Small Normal||23 (5.8)|