Maternal ABO Blood Group and the Risk of Preeclampsia and Pregnancy Outcomes in a Nigerian Tertiary Care Hospital

Abstract

Background: Preeclampsia is a multisystemic disorder that contributes significantly to maternal morbidity and mortality including adverse pregnancy outcomes. Though the aetiology is unknown, various risk factors including the ABO blood group have been linked with its occurrence. However, results from studies that assess the association between the ABO blood group and the risk of preeclampsia have been inconsistent. This study aimed to determine the association between maternal ABO blood group and the risk of preeclampsia as well as their pregnancy outcomes.
Materials and Methods: This was a prospective case-control study. A total of 198 consented participants consisting of 99 preeclamptic parturients (cases) and 99 normal parturients (controls) were consecutively recruited into the study from the ante-natal clinic for 6 months. Information including age, educational status, parity, ABO blood group, and pregnancy outcomes were obtained from participants’ hospital records into a proforma designed for the study. Inferential statistics, Chi-square, and student t-test were used as appropriate, the p-value was set at 0.05.
Results: Blood group O was the most common among the study participants (75.8% and 76.8% for cases and controls respectively), while the B- blood type was the least represented (9.1% and 10.1% respectively). There was no association between the maternal ABO blood group and the risk of preeclampsia (p=0.904). However, there was an association between maternal educational level and parity and the risk of preeclampsia (p = 0.014 & 0.001 respectively). Furthermore, preeclamptic women were more likely to have adverse pregnancy outcomes (p=0.0001).
Conclusion: Like other similar studies, we found no association between maternal ABO blood and the risk of preeclampsia. However, maternal educational level and parity were associated with the risk of preeclampsia. Furthermore, preeclampsia harms pregnancy outcomes. Therefore, parity and educational level may be considered potential risk factors for preeclampsia during antenatal follow-up.