From the Research
Labor can significantly impact lactate levels, with a notable increase in lactate levels during the second stage of labor, particularly after 30 minutes of pushing, as evidenced by a mean change in lactate level of 2.0 ± 1.8 mmol/L or 0.07 ± 0.06 mmol/L/min (p < 0.01) 1.
Key Findings
- Lactate levels increase significantly once a patient reaches complete cervical dilation within 30 minutes of pushing 1.
- The change in lactate level during normal labor is more pronounced in patients with chorioamnionitis, although this difference is not statistically significant (p = 0.41) 1.
- Fetal lactate levels also increase during labor, particularly if there is any compromise to oxygen delivery, as might occur with umbilical cord compression or prolonged contractions 2.
Clinical Implications
- Clinicians should be aware that lactate levels can be elevated in uncomplicated labor, and this increase is a normal physiological response to the intense physical exertion and muscular activity involved in contractions 1, 3.
- Understanding these changes is important for properly interpreting lactate measurements obtained during labor and avoiding misdiagnosis of other conditions that can cause elevated lactate 1, 3.
- Lactate levels typically return to normal within hours after delivery as the body clears the accumulated lactic acid 3.
Recommendations
- Lactate levels should be interpreted with caution during labor, taking into account the stage of labor and the presence of any complications 1, 3.
- Clinicians should consider the normal range of lactic acid in healthy pregnant women during labor when interpreting lactate measurements, which can be used as a screening tool to identify potential complications 3.