Abstract
This study investigates the relationship between placental weight relative to birthweight
and risk of stillbirth in non-dysmorphic fetuses ≥ 38 weeks gestation with no evidence
of intrauterine growth restriction. This is a retrospective study of stillbirths who
underwent post-mortem between 1st Jan 2011 and 31st Dec 2018 in South East Scotland
(n = 55). The control group (n = 74) was matched for gestation, age of mother and
maternal BMI. There was a significant difference (p = 0.0117) in the mean ratio of birth weight to placental weight (BW:PW) between the
stillbirth group (8.17) and control group (7.33). Cases of stillbirths where the mother
had reported reduced fetal movements (RFM) had a higher BW:PW compared to controls
(p = 0.024). Within the RFM stillbirth group, 5/6 (83%) cases showed significant changes
of maternal vascular malperfusion (MVM) and/or fetal vascular malperfusion (FVM);
whilst within the RFM control group, 5/15 (33%) cases showed significant changes of
MVM and/or FVM. There is a significantly higher BW:PW within the stillbirth group
than within the control group, both groups show changes of MVM and/or FVM and our
supposition is that these changes have a greater impact on placental reserve when
the birthweight is high relative to placental weight. Reduced fetal movements may
indicate diminished placental reserve. We propose that the ability to predict a high
BW:PW within pregnancies where the mothers report RFM may help to prevent late stillbirth
in non-IUGR infants.
Keywords Stillbirth - Placenta - Pathology - Screening
