Differences in post‐mortem findings after stillbirth in women with and without diabetes

Abstract

In over half of the stillbirths occurring in women with diabetes, there was a 'starry sky' appearance in the fetal thymus on histology, this being associated with a small placenta. These findings are consistent with a critical subacute metabolic disturbance being a prominent cause of the increased risk of stillbirth in pregnancies complicated by maternal diabetes.

Women with pre‐gestational diabetes have a higher risk of stillbirth at all gestations after 32 weeks

“…Maternal vascular disease, increased fetal oxygen demand through myocardial hypertrophy (secondary to fetal hyperinsulinaemia) and transient episodes of hypoxia associated with increasing uterine contractions in the third trimester may also contribute. Such factors are in accord with post-mortem findings suggesting that subacute metabolic disturbance was a prominent cause of stillbirth [15]. Fetal growth restriction is a key indicator of increased stillbirth risk and this should be detected via frequent growth scans in women with diabetes.…”

Quantitative assessment of placental morphology may identify specific causes of stillbirth

“…This pilot study demonstrates that objective assessment of placental morphology may provide additional information on placental villous structure in cases of stillbirth and in some cases, such as in FGR, can differentiate between specific causes of stillbirth and healthy live-born infants. In other cases, such as stillbirths attributed to maternal diabetes, there were no morphological differences from live-born infants, which is consistent with few histopathological abnormalities in stillbirths related to diabetes [ 26 ]. When the morphometric profile was applied to ten stillbirths of unknown cause, two had a very similar placental profile to FGR, which suggests that some stillbirths that currently have no identified cause (despite intensive investigation) may actually result from FGR in a fetus that was not small, i.e.…”

Assessment of first‐trimester thymus size and correlation with maternal diseases and fetal outcome

“…This may be explained by an immune response from the fetal immune system as a result of the maternal rheumatic diseases. A decreased thymus size in pregnancies affected by maternal diabetes may be caused by subacute stress of the fetus caused by a metabolic disturbance secondary to maternal diabetes . This thymic involution may be associated with a histological finding of cortical lymphocyte depletion .…”