Introduction:
Postpartum hemorrhage (PPH), a major cause of maternal mortality, has several known
risk factors but often occurs unexpectedly. We aimed to evaluate the impact on PPH
of defined prepartum blood coagulation parameters, notably factor XIII.
Methods:
Our single-center prospective study analyzed the prepartum activities of coagulation
factors II and XIII, together with fibrinogen levels, in 1300 women. Blood samples
were obtained at labor onset and analyzed only after the last patient had delivered,
to prevent the results influencing the management of subsequent patients. Blood loss
was quantified using a validated technique and assessed for correlation with coagulation
factors using continuous outcome logistic regression.
Results:
Factor XIII activity correlated closely with measured blood loss: for every unit (%)
increase in factor XIII, the odds ratio for remaining below any given cut-off for
blood loss was 1.011 (95% confidence interval, 1.006 to 1.015; P < 0.001). We calculated
that a 30% increase in factor XIII activity would increase the odds of not suffering
PPH by 38.9%. This effect was independent of a statistical model, present after stratification
by delivery mode, at all blood loss cut-offs, and when considering other risk factors.
Factor II had a similar but much weaker effect, fibrinogen had none.
Abb. 1
Discussion:
In the largest population analyzed to date, prepartum factor XIII activity correlated
closely with postpartum blood loss across every statistical model and clinical subgroup.
Interestingly, prepartum F. I did not have any effect on postpartum blood loss. These
results may therefore strengthen the case for initial enzyme (coagulation factor)
over substrate (fibrinogen) replacement, and/or the order in which they are given.
Boosting factor XIII levels could constitute a new tool in the prevention and effective
early treatment of PPH.
