Platelet count in preeclampsia: a systematic review and meta-analysis

Area of Science:

• Obstetrics and Gynecology
• Hematology
• Reproductive Medicine

Background:

• Preeclampsia is a serious pregnancy complication with unclear etiology.
• Previous studies on the association between platelet count and preeclampsia had small sample sizes and inconsistent findings.

Approach:

• A systematic literature search was conducted across multiple databases up to April 2022.
• A meta-analysis of 56 observational studies involving 4892 preeclamptic and 9947 normotensive pregnant women was performed.
• Statistical analyses included calculating mean differences, assessing heterogeneity, and performing sensitivity and subgroup analyses.

Key Points:

• Platelet count was significantly lower in women with preeclampsia compared to normotensive controls (mean difference: -32.83).
• Lower platelet counts were observed in mild and severe preeclampsia, during the second and third trimesters, and even before clinical diagnosis.
• The pooled sensitivity and specificity of platelet count for identifying preeclampsia were 0.71 and 0.77, respectively, with an AUC of 0.80.

Conclusions:

• This meta-analysis provides robust evidence that reduced platelet count is a consistent finding in preeclampsia.
• Platelet count may serve as a valuable biomarker for the early identification and prediction of preeclampsia.
• The findings highlight the importance of monitoring platelet levels during pregnancy, particularly in the second and third trimesters.