Photo by Nina Matthews
Pregnant woman
In a large study, men who received blood from women with a history of pregnancy had an increased risk of death after transfusion.
However, receiving blood from a woman who was never pregnant did not carry the same risk.
And female recipients of blood transfusions had a similar risk of death whether they received blood from women with or without a history of pregnancy.
Rutger A. Middelburg, PhD, of Sanquin Research in Leiden, Netherlands, and his colleagues reported these results in JAMA.
The researchers noted that the most common cause of transfusion-related mortality is transfusion-related acute lung injury, which has been associated with transfusions from female donors, specifically those with a history of pregnancy.
Therefore, Dr Middleburg and his colleagues set out to determine whether an increased risk of mortality after red blood cell transfusions could depend on the donor’s history of pregnancy.
The team studied first-time transfusion recipients at 6 major Dutch hospitals.
When the researchers looked only at patients who received blood from a single type of donor (male/female with pregnancy history/female without), there was a significantly higher risk of death among men who received blood from females with a history of pregnancy.
Male recipients
There were 1722 deaths among the 12,212 males who only received blood from male donors (hazard ratio [HR]=1.00).
There were 1873 deaths among the 13,669 males who only received blood from females with a history of pregnancy (HR=1.13, P=0.03).
And there were 1831 deaths among the 13,538 men who only received blood from females without a history of pregnancy (HR=0.93, P=0.29).
Female recipients
There were 1752 deaths among the 13,332 females who only received blood from male donors (HR=1.00).
There were 1871 deaths among the 14,770 females who only received blood from females with a history of pregnancy (HR=0.99, P=0.92).
And there were 1868 deaths among the 14,685 females who only received blood from females with no history of pregnancy (HR=1.01, P=0.92).
Role of age
The researchers also found the association between donor pregnancy history and recipient death was only observed for men younger than 51.
There were 107 deaths among the 2251 males ages 0 to 17 who received blood from male donors (HR=1.00). And there were 124 deaths among the 2556 males ages 0 to 17 who received blood from females with a history of pregnancy (HR=1.63, P=0.04).
There were 84 deaths among the 1170 males ages 18 to 50 who received blood from male donors (HR=1.00). And there were 94 deaths among the 1296 males ages 18 to 50 who received blood from females with a history of pregnancy (HR=1.50, P=0.06).
There were 598 deaths among the 4292 males ages 51 to 70 who received blood from male donors (HR=1.00). And there were 645 deaths among the 4775 males ages 51 to 70 who received blood from females with a history of pregnancy (HR=1.10, P=0.31).
There were 933 deaths among the 4499 males ages 71 and older who received blood from male donors (HR=1.00). And there were 1010 deaths among the 5042 males ages 71 and older who received blood from females with a history of pregnancy (HR=1.06, P=0.47).
The researchers said more work is required to replicate these findings, determine their clinical significance, and identify the underlying mechanism.
