Hemostatic profile during late pregnancy and early postpartum period in mares.

This study investigated how a mare’s blood-clotting profile changes during late pregnancy and early postpartum period to prevent excessive bleeding during and after the birthing process. A total of 30 mares – 15 pregnant and 15 non-pregnant – were studied to better understand the physiological conditions that contribute to a potentially dangerous condition known as peripartum hemorrhage.

Objective of the Study

• The study aimed to understand the changes in a mare’s hemostatic (blood-clotting) system during late pregnancy and the early postpartum period. The objective was to determine if there are physiological adjustments that occur to prevent potential peripartum hemorrhage, a condition that often poses a risk to the mare’s health around the time of childbirth.

Study Design and Methodology

• The researchers had a sample size of 15 pregnant mares monitored from the 34th week of pregnancy into the third week postpartum. Fifteen non-pregnant mares were used as a control group.
• The mares’ blood samples were drawn from the jugular vein and analysed for platelet count, prothrombin time (PT), activated partial thromboplastin time (aPTT), and fibrinogen levels – these indicators give a comprehensive picture of a body’s clotting ability.

Key Findings

• Platelet levels, a key agent in blood clotting, showed significant changes at the time of parturition (P < 0.05) and also displayed a negative correlation postpartum with r = -0.968; P = 0.032.
• Prothrombin time, which is an indicator of how quickly blood clots, changed with a significant correlation (r = 0.675; P = 0.016) during late pregnancy, suggesting that the body adjusts clotting mechanisms in anticipation of delivery to prevent massive bleeding.
• Fibrinogen levels, which contribute to the final step of the blood clotting process, showed variation throughout the experiment (P < 0.0001), with a positive correlation (r = 0.9210; P < 0.0001) in late pregnancy and a negative correlation postpartum (r = -0.9583; P = 0.042). This implies that levels increase to prevent excessive bleeding during childbirth and decrease afterwards.

Conclusion

• The researchers concluded that the changes in platelet count, prothrombin time, and fibrinogen concentrations during late pregnancy through to early postpartum in mares suggest that the body naturally adjusts to a hypercoagulable state. This supports faster blood clotting to prevent excessive bleeding, enhancing survival chances during and after delivery.
• The findings provide valuable insights into the blood coagulation process in equine periparturition and help establish useful parameters for monitoring maternal hemostatic profiles during these crucial periods.