Abstract
AimTo evaluate the association between lactate concentrations in fetal blood samples and the different advanced labour stages. MethodsEighteen-month prospective population-based clinical study of 187 singleton pregnant women in labour who were monitored by fetal blood sampling (FBS) because of non-reassuring intrapartum CTG results at Kuopio University Hospital, Finland. Peripheral lactate concentration and pH were analysed at different stages of labour and in umbilical arterial samples immediately after delivery. ResultsFBS samples (N = 350) were obtained from 5.4 % of all women in labour during the study period, and 48 % had spontaneous delivery, 27 % had vacuum-assisted vaginal delivery, and 25 % had nonelective Caesarean delivery. FBS lactate levels increased 4–11% with every 1–2 cm of cervical dilation and 18 % from early labour to fully dilated cervix. In 42 women with at least two FBSs, lactate levels increased significantly from the early I stage of labour and up to a fully dilated cervix. Lactate values were significantly higher in umbilical arterial samples compared to FBSs. Sensitivity of the highest FBS lactate values for the detection of birth asphyxia were considerably low varying between 42.9–57.1%. ConclusionFBS lactate levels were related to the stage of labour during vaginal delivery attempt. Wide range of lactate levels during labour complicates its use as a predictor of birth asphyxia.
Highlights
Vaginal delivery is usually a stressful process for both the mother and fetus
Excluding women who underwent elective Caesarean delivery (N = 178), fetal blood sampling (FBS) was obtained from 5.4 % (N = 187) of all women with trial of labour
The main finding in this study was that FBS lactate values increased in 80 % of women with serial sampling during advanced labour, and these values were associated with the stage of labour at the time of sampling
Summary
Vaginal delivery is usually a stressful process for both the mother and fetus. Placental and further fetal peripheral oxygen supply may decrease during the labour process for many various acute reasons, such as uterine hypercontractility, reduced placental blood flow, or compression of the umbilical cord. Healthy fetuses are able to compensate for the short period of hypoxemia. Anaerobic metabolism starts if adequate oxygen supply to the fetus is not available. Lactic acid is produced from glucose and glycogen. This reaction is much less efficient compared to aerobic energy production, it is proposed to be one of the fetal survival mechanism to maintain cardiac function and brain oxygen supply during hypoxia, besides other well-known compensatory mechanisms [1]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
