Mean Platelet Volume (whole blood)
MPV reflects average platelet size. Larger platelets are more reactive and often indicate increased marrow production. MPV rises slightly across pregnancy.
| Units | Nonpregnant Adult | 1st Trimester | 2nd Trimester | 3rd Trimester |
|---|---|---|---|---|
| fL (µm³) | 6.4 – 11 | 7.7 – 10.3 | 7.8 – 10.2 | 8.2 – 10.4 |
Pregnancy physiology
- MPV increases slightly during pregnancy due to accelerated platelet turnover.
- Normal hemodilution lowers platelet count, but platelets released may be larger.
- MPV should be interpreted along with platelet count and clinical context (e.g., preeclampsia evaluation).
Causes of elevated MPV
- Normal pregnancy increase
- Preeclampsia / hypertensive disorders (increased platelet activation)
- Immune thrombocytopenia (ITP) — large young platelets
- Recovery after hemorrhage or marrow suppression
- Myeloproliferative disorders
- Inflammatory disorders
Cited references:
• Abbassi-Ghanavati et al., Obstet Gynecol 2009.
• Bain BJ, Blood Cells (Wiley).
• Danise et al., Platelet parameters in pregnancy.
Causes of low MPV
- Aplastic anemia or marrow hypoplasia
- Wiskott–Aldrich syndrome
- Chronic renal disease
- Chemotherapy or radiation
- Severe hypothyroidism
- Lab artifact (old sample → swelling/fragmentation)
Cited references:
• Williams Hematology.
• Bain BJ — Blood Cell Morphology.
• Abbassi-Ghanavati table of pregnancy laboratory values.
References
- Abbassi-Ghanavati M, Greer LG, Cunningham FG. Pregnancy and laboratory studies: a reference table for clinicians. Obstet Gynecol. 2009;114:1326–31.
- Bain BJ. Blood Cells: A Practical Guide. Wiley-Blackwell.
- Danise P et al. Platelet indices in pregnancy: clinical interpretation. Hematology Reviews.