Transfusions may protect against SCD pregnancy complications
Regular blood transfusions during pregnancy linked to fewer adverse outcomes
Preventive red blood cell transfusions may protect against complications associated with pregnancy in women with sickle cell disease (SCD), a 13-year study has found.
Findings indicate that the rates of premature births, as well as SCD complications, such as vaso-occlusive crises (VOCs) and acute chest syndrome (ACS), are all significantly lower among pregnant women who receive regular blood transfusions.
The study, “Evaluation of a prophylactic transfusion programme on obstetric outcomes in pregnant women with sickle cell disease: a single centre retrospective cohort study,” was published in the European Journal of Obstetrics & Gynecology and Reproductive Biology.
Pregnant women with SCD at higher risk of adverse maternal outcomes
Pregnant women with SCD are at a higher risk of experiencing adverse maternal outcomes, including pre-eclampsia (high blood pressure accompanied by organ damage), blood clotting problems, and infections. Fetal complications may include pre-term (premature) birth, limited growth, and death.
Other frequent SCD-related maternal complications include VOCs, which occur when red blood cells block blood flow, causing inflammation and pain; and ACS, which is caused by blood vessel blockage in the lungs and is generally characterized by fever, chest pain, and difficulty breathing.
Preventive (prophylactic) red blood cell transfusion is an approach currently available for SCD patients during pregnancy to prevent such complications by replacing sickled red blood cells with healthy ones.
While studies indicate that transfusions starting in the early weeks of pregnancy may improve outcomes for both mother and newborn, “there is currently insufficient evidence to recommend [prophylactic transfusion] as standard care during pregnancy,” the researchers wrote.
To investigate further, the team examined the outcomes of 246 pregnancies in 173 SCD patients over a 13-year period. All women had received prenatal care and given birth in a French university tertiary care center from January 2004 to December 2017.
A red blood cell [transfusion] may have an independent protective effect on maternal and perinatal adverse outcomes during pregnancy in women with SCD.
A total of 22 pregnancies were excluded due to a history of delayed hemolytic transfusion reaction (DHTR), a type of adverse reaction to a blood transfusion. Of the remaining patients, 148 (66%) received regular transfusions during pregnancy and 76 (34%) did not.
Four cases of DHTR occurred in the group of women who received transfusions, as well as in the group of those who did not. Additionally, four maternal deaths were observed in the transfusion group.
No differences were seen in the rates of cesarean section and several pregnancy complications, including pre-eclampsia, eclampsia, and HELLP syndrome (hemolysis, elevated liver enzymes, and low platelets), between the two groups.
Pre-term births before 37 weeks occurred significantly less often in the transfusion group compared with the non-transfusion group (19.4% vs. 33.8%), as did births occurring before 34 weeks (5.6% vs. 19.7%).
Rates were also significantly lower in the transfusion group for VOCs (36.5% vs. 61.8%) and ACS (6.1% vs. 14.5%).
In the non-transfusion group, there was a non-significant trend in higher composite scores for adverse obstetric outcomes than in the transfusion group (34.2% vs. 23.7%). Composite (combined) scores reflected the occurrence of various adverse events, including early birth (before 34 weeks), pre-eclampsia, small fetal size, abruption (placenta separating from womb walls before birth), fetal death, maternal death, and newborn death.
Transfusions linked to reduction in rick of adverse outcomes
The frequency of transfusions was lower among those with composite adverse outcomes than in those without (52.6% vs. 74.7%). It was also lower among women in whom childbirth occurred before 34 weeks (28.4% vs. 75.3%).
After statistical adjustments, red blood cell transfusions were found to be significantly associated with a 72% relative reduction in the risk of composite obstetric adverse outcomes.
Of the 22 pregnancies with a DHTR history who were excluded from the primary analysis, four experienced a new DHTR event after an emergency transfusion. Rates of early delivery, neonatal death, ACS, maternal intensive care unit hospitalization, and composite adverse outcomes were significantly higher in those with a DHTR history.
“A red blood cell [transfusion] may have an independent protective effect on maternal and perinatal adverse outcomes during pregnancy in women with SCD,” the team wrote.