Contraction monitor how does it work

You may end up with electronic fetal monitoring for a time — or, if necessary, for the duration of your labor. For low-risk pregnancies, experts agree there's no need for continuous fetal monitoring.

Periodic monitoring intermittent auscultation is just as effective. A few studies have found that babies may be marginally safer when monitored continuously, but results are inconclusive. What's more, using continuous monitoring in low-risk pregnancies can increase the risk of false readings that lead to the mother undergoing unnecessary procedures.

Even if your pregnancy and labor are low risk, chances are high you'll receive continuous fetal monitoring. Intermittent auscultation is more labor intensive for hospital staff, so hospitals and practitioners generally prefer continuous fetal monitoring for all laboring women, regardless of risk factors.

That said, if you have a low-risk pregnancy and no complications during labor, the American College of Obstetricians and Gynecologists considers intermittent auscultation an acceptable method. And it's the preferred method of the American College of Nurse-Midwives for women with no risk factors. That's because intermittent auscultation is associated with fewer c-sections and forceps and vacuum deliveries, and there's no proof that it makes any difference for the babies.

Yes, if you're planning an unmedicated childbirth and don't have any high-risk conditions. Discuss your preference with your practitioner. Find out ahead of time about her views, the hospital policy, and whether or not there's typically enough staff available for the intermittent checks. In most practices in which intermittent monitoring is an option, your provider may still want to connect you to the monitor for an initial to minute check when you're admitted to the hospital in labor.

If you're laboring in a birth center or at home, you'll definitely be monitored intermittently. You'll have a caregiver with you at all times so the checks can be performed as frequently as needed. If you develop a condition that requires continuous monitoring, you'll need to be transferred to a hospital.

Your practitioner may do internal fetal heart rate monitoring if the external monitor isn't picking up well which sometimes happens if you're moving around a lot or are obese or she has concerns and wants a more accurate reading,. An internal heart rate monitor is connected to a wire electrode that is inserted through your cervix and placed onto the part of your baby that is closest, usually the scalp. Your practitioner may also decide to get more information about the strength of your contractions by inserting a special catheter-like gauge through your cervix for internal uterine monitoring.

If your baby's heart rate is persistently flat, slow or fast your provider may try some simple interventions. These include:. Depending on your situation, other interventions may be necessary, too. These might include. Keep in mind that some dips in a baby's heart rate are normal. Also, certain heart rate changes are considered a sign of well-being.

For example, when your baby moves, his heart rate should go up, just as yours does when you exercise. Don't panic if you've been listening to the galloping of your baby's heartbeat and it suddenly stops. Most likely, the transducer on your belly has shifted out of place and lost contact with the heartbeat. Call the nurse so she can adjust it.

Throughout labor, your practitioner will evaluate your baby's heart rate frequently and watch for anything that could signal a problem. Even if someone is not present with you in your room, don't worry.

Most hospitals have central monitoring where providers and nurses can watch fetal heart rates from afar. BabyCenter's editorial team is committed to providing the most helpful and trustworthy pregnancy and parenting information in the world.

When creating and updating content, we rely on credible sources: respected health organizations, professional groups of doctors and other experts, and published studies in peer-reviewed journals. We believe you should always know the source of the information you're seeing. A collection of interactive medical and surgical clinical case scenarios to put your diagnostic and management skills to the test.

Each clinical case scenario allows you to work through history taking, investigations, diagnosis and management. A collection of free medical student quizzes to put your medical and surgical knowledge to the test!

Table of Contents. Cardiotocography CTG is used during pregnancy to monitor fetal heart rate and uterine contractions. It is most commonly used in the third trimester and its purpose is to monitor fetal well-being and allow early detection of fetal distress.

An abnormal CTG may indicate the need for further investigations and potential intervention. The device used in cardiotocography is known as a cardiotocograph. It involves the placement of two transducers onto the abdomen of a pregnant woman. One transducer records the fetal heart rate using ultrasound and the other transducer monitors the contractions of the uterus by measuring the tension of the maternal abdominal wall providing an indirect indication of intrauterine pressure.

The CTG is then assessed by a midwife and the obstetric medical team. To interpret a CTG you need a structured method of assessing its various characteristics. When performing CTG interpretation, you first need to determine if the pregnancy is high or low risk. This is important as it gives more context to the CTG reading e. Some reasons a pregnancy may be considered high risk are shown below.

Next, you need to record the number of contractions present in a 10 minute period. Each big square on the example CTG chart below is equal to one minute , so look at how many contractions occurred within 10 big squares. Individual contractions are seen as peaks on the part of the CTG monitoring uterine activity.

The baseline rate is the average heart rate of the fetus within a minute window. Look at the CTG and assess what the average heart rate has been over the last 10 minutes, ignoring any accelerations or decelerations. A normal fetal heart rate is between bpm. Fetal tachycardia is defined as a baseline heart rate greater than bpm.

Fetal bradycardia is defined as a baseline heart rate of less than bpm. Severe prolonged bradycardia less than 80 bpm for more than 3 minutes indicates severe hypoxia. Causes of prolonged severe bradycardia include:.

Baseline variability refers to the variation of fetal heart rate from one beat to the next. Variability occurs as a result of the interaction between the nervous system , chemoreceptors , baroreceptors and cardiac responsiveness.

It is, therefore, a good indicator of how healthy a fetus is at that particular moment in time, as a healthy fetus will constantly be adapting its heart rate in response to changes in its environment. To calculate variability you need to assess how much the peaks and troughs of the heart rate deviate from the baseline rate in bpm. Variability can be categorised as either reassuring , non-reassuring or abnormal.

Reduced variability can be caused by any of the following: 2. Accelerations are an abrupt increase in the baseline fetal heart rate of greater than 15 bpm for greater than 15 seconds.

Accelerations occurring alongside uterine contractions is a sign of a healthy fetus. The other plate on the CTG measures how tense the mother's tummy abdomen is. This measurement is used to show when the uterus is contracting. Many different things can be recorded on a CTG; your baby's heart rate, the baby's movements and your contractions. These are all shown on the image below. It is normal for a baby's heart rate to vary between and beats a minute.

This is much faster than your own heart rate, which is about beats per minute. A heart rate in your baby that doesn't vary or is too low or too high may mean that there is a problem. Your doctor or midwife may need to do further tests to check. Changes in the baby's heart rate that occur along with contractions form a pattern. Certain changes in this pattern may suggest a problem. If test results suggest your baby has a problem, your doctor may decide to deliver the baby right away. This may mean you need to have a caesarean section or an assisted delivery using forceps.

In a normal, low-risk delivery, CTG is not usually needed. The midwife will listen to your baby's heart rate from time to time to check it is normal. However, in certain situations, continual monitoring with CTG is advised. These include:. If you are having a CTG and the trace remains normal over 20 minutes, it will usually be removed.

CTG does not use any radiation; it is considered a very safe test. Depending on the machine used, it may prevent you from being able to move around freely during labour.

If CTG is used when it is not necessary, it may be that it increases the chances of having interventions such as forceps or caesarean section that weren't really needed.

Women who have infections such as herpes, hepatitis B or C or HIV do not usually have internal monitoring, as it may increase the chance of passing the infection on to the baby. Cochrane Database Syst Rev. My girlfriend took 6 at home pregnancy tests - 4 were positive. The nurse couldn't give us an exact diagnosis - only her own opinion on whether or not my girlfriend Disclaimer: This article is for information only and should not be used for the diagnosis or treatment of medical conditions.

Egton Medical Information Systems Limited has used all reasonable care in compiling the information but make no warranty as to its accuracy. Consult a doctor or other health care professional for diagnosis and treatment of medical conditions. For details see our conditions.