This is a protocol for a Cochrane Review (Intervention). The objectives are as follows:

To evaluate the effectiveness and risks of fetal scalp lactate sampling in the assessment of fetal wellbeing during labour, compared with no testing or alternative additional testing (pH, fetal pulse oximetry, etc) for women exhibiting a non‐reassuring cardiotocograph trace.

A secondary objective of the review is to determine whether effectiveness and risks of intrapartum fetal scalp lactate sampling is influenced by the following:

• stage of labour;

• gestation less than 37 completed weeks, greater than or equal to 37 completed weeks;

• additional tests performed to confirm the presence or absence of fetal acidemia during labour.