Fetal scalp pH testing

Fetal Scalp pH Testing: What Is It and When Do Doctors Perform It?

Fetal scalp pH testing is a medical procedure during childbirth that can measure if the baby is getting enough oxygen. Normally the fetus defends against low oxygen levels by releasing extra red blood cells. During the procedure, a small sample of the baby's scalp is taken and checked for its pH level. This procedure is also known as fetal scalp pH sampling or cordocentesis.

What is Fetal Scalp pH testing?

Fetal scalp pH testing is a procedure that measures the pH balance of the fetal scalp and is an indicator of the fetal oxygenation. A normal fetal scalp pH is between 7.25 and 7.45. A test result outside this range may mean the baby is having difficulty getting enough oxygen, and delivery of the baby is recommended.

Preparation for Fetal Scalp pH testing

Before the test is performed, the healthcare provider will explain the procedure in detail. The mother is given the opportunity to ask any questions related to the procedure. The monitoring of the baby's heartbeat during the procedure is important. The healthcare provider may then administer antibiotics and numbing medication, if necessary, to reduce discomfort during the procedure.

Procedure of Fetal Scalp pH testing

The procedure involves the insertion of a small, thin needle through the abdomen of the mother and into the scalp of the baby. The needle is then used to obtain a sample of the scalp for testing. The procedure usually takes only a few minutes.

Types of Fetal Scalp pH Tests

There are two types of fetal scalp pH tests: direct sampling and indirect sampling. With direct sampling, a small amount of scalp cells is taken immediately and tested. In the indirect sampling method, a sample of the umbilical cord blood is taken and tested for pH.

Risks of Fetal Scalp pH testing

Although the procedure is considered to be fairly safe, there is still a risk of some potential complications, such as short-term or long-term damage to the fetal scalp, infection, bleeding and fetal distress. There may also be a risk of scarring or a permanent indentation in the baby's scalp.

Why Do Doctors Perform Fetal Scalp pH Testing?

Fetal scalp pH testing is used to assess the fetal oxygen levels and is an important tool in monitoring the health of the fetus during childbirth. It can help the healthcare provider to determine if the baby is receiving enough oxygen or if there is a potential oxygen deprivation and the baby needs to be delivered immediately.

When is Fetal Scalp pH Testing Performed?

Fetal scalp pH testing is typically performed when there are signs of fetal distress during labor, such as decreased fetal heart rate, late decelerations, or if the mother is going into a labor which is extended or complicated. The clinician will weigh the risks and benefits and decide whether a fetal scalp pH test should be performed.