IN THE LIT

R. M. Pauli, MD, Ph.D.

Antiphospholipid antibodies and risk of intrauterine late fetal death. Bocciolone L, Meroni P, Parazzine F et al. Acta obstet gynecol Scand 73:389-392, 1994.

A large number of studies have shown correlation between the presence of lupus anticoagulant activity and anticardiolipin antibodies in the mother and fetal death. It has been postulated that the presence of these anomalous antibodies increases the risk of thrombotic phenomena, placental infarction and placental vasculopathy. Furthermore, there is some evidence that this may be a preventable cause of recurrent intrauterine death. This case-control study was undertaken to estimate the frequency with which later (beyond 20 weeks gestation) fetal death is associated with the presence of lupus anticoagulant activity and anticardiolipin antibodies. Overall, of those experiencing late intrauterine death, 4% (4/99) had positive lupus anticoagulant activity and 11% (10/89) had anticardiolipin antibodies. None of the controls had either activity detectable. This is one of the better controlled studies to date. It suggests that somewhere around 5-10% of all stillbirths may be associated with (and, very possibly caused by) the presence of one or both of these maternal antibodies. Postnatal assessment of these factors seems appropriate in women with recurrent pregnancy losses and in those instances of intrauterine death in which placental infarction, fibrosis or vasculopathy is demonstrated. Whether routine screening following all stillbirths is warranted remains an open question.

Confined placental mosaicism and stillbirth. Kalousek DK, Barrett I. Pediat Pathol 14:151-159, 1994.

This is for the most part an hypothesis paper. Confined placental mosaicism is a phenomenon where there is a discrepancy between the chromosomal constitution of the fetus and of the placenta. Most frequently the placenta is found to be trisomic while the fetus has normal cytogenetic findings. This probably arises through 'cure' of fetal cells postzygotically through the spontaneous loss of one of the three copies of the trisomic chromosome. Such loss is presumably random and, therefore, sometimes the two remaining copies of that chromosome will both be either maternally or paternally derived. This is termed uniparental disomy. Uniparental disomy can result in problems since some genes function very differently depending on whether they are paternally or maternally derived (imprinting). Thus, uniparental disomy may be the mechanism through which confined placental mosaicism might be correlated with fetal death. That is, the uniparental disomy (rather than the chromosomal abnormality in the placenta) might be the factor which results in lethality. This is a fascinating hypothesis which needs to be tested. [In fact, WiSSP is currently collaborating with researchers at the National Institutes of Health in an effort to assess how often, if ever, this process is causal in stillbirth.]

Maternal attitude toward pregnancy and the risk of neonatal death. Bustan MN, Coker AL. Am J Pub Health 84:411-414, 1994.

I couldn't resist this title. It does, indeed, accurately reflect what these researchers from the University of South Carolina investigated through recovery of data from a cohort of pregnant women first investigated three decades ago: Do negative attitudes toward a pregnancy increase the risk of perinatal mortality. On its face, this seems a bizarre hypothesis. However, stress and other factors have been correlated with an increased risk of miscarriage, spontaneous resorption, etc. in a nimals. Furthermore, it is common for families to ask us whether anxiety, stress, negative feelings and so forth might contribute to the death of their baby. After controlling for all confounding variables, and assessing only married couples, there was a more than two fold increased risk for death in th e first month of life; however, there was no significant increased risk for fetal death. Therefore, there was no evidence that unwanted pregnancy is correlated with stillbirth, but why is there the apparent relationship to neonatal death? Cause of death was not coded and so from this study we will never know. Could a rate such as this simply reflect non-accidental trauma? Might one in every hundred unwanted infants suffer such a fate?