Fetal Movement

Article Author:
Joy Bryant
Article Editor:
Jennifer Thistle
Updated:
10/27/2018 12:31:35 PM
PubMed Link:
Fetal Movement

Introduction

Fetal movement felt by a pregnant woman are a sign that the fetus is growing in size and strength. The pregnant woman is usually the first to feel these movements which can later be felt by others. Women are often taught by their health care provider to monitor or be aware of the movements of the fetus. This can be a general awareness of fetal movements, or the women can be taught to count the number of kicks they feel in a set amount of time.

Decreased fetal movement can be a warning sign of potential fetal impairment or risk, and therefore, warrants further evaluation by the healthcare provider.

Function

The first fetal movements which are felt by the mother are called quickening. One function of these movements is to alert the pregnant woman that she has a fetus growing in her uterus. Quickening often occurs between 16 to 22 weeks of the pregnancy. Quickening is called a presumptive sign of pregnancy because other movements of the woman's body can mimic early fetal movements such as peristalsis, flatus, and abdominal muscle contractions. A multiparous woman will usually notice these gentle fluttering movements of the fetus at an earlier gestation than a primiparous woman. A multip might feel movements as early as 16 weeks whereas a primip might not feel anything until 20 to 22 weeks. Around 20 weeks gestation, the trained healthcare provider (HCP) can feel fetal movement externally through the abdomen, and this is considered a positive sign of pregnancy. 

Most providers recommend that pregnant woman monitor fetal movements, especially by the third trimester. This can be accomplished by simply instructing the woman to have a general awareness of the fetus and determine if the fetus is moving less than normal on any given day or about the same as other days. Alternatively, healthcare providers might recommend a more formal fetal movement count (FMC), sometimes called a kick count. Clinicians often recommend starting this surveillance around 28 weeks gestation and continuing throughout the remainder of the pregnancy. The "count to 10" method includes the instructions for the woman to count fetal movements at the same time each day. If the woman experiences less than ten movements in a 2 to 3-hour period, she is instructed to contact her healthcare provider. One study noted that having women count fetal movements can improve maternal-child bonding during pregnancy as the mother starts to get to know her unborn child.

Issues of Concern

The issues of concern would include perceived or actual decreased fetal movement. Historically, cases of a compromised fetus or infant have usually been preceded by decreased fetal movement. Therefore, the assumption is that if a woman notices a decrease in fetal movement and has it evaluated, then a possible adverse event with the fetus might be avoided by the use of interventions. Many studies have attempted to verify a correlation between decreased fetal movement and placental functioning, abnormalities of the uterus, fetal growth restriction, twin to twin transfusion, tight nuchal cords, or to demonstrate that kick counts can prevent intrauterine fetal demise. Although this type of monitoring is often recommended, tracking does not always prevent complications. However, due to the low cost and potential benefit, it is recommended. Decreased fetal movement can indicate a need for more evaluation and has the potential to save lives. 

One potential side effect of routine monitoring of fetal movement could be an increase in prenatal visits, either outpatient or in hospital. However, most research has not found this type of increase to be true. Usually, the fetal movement count (FMC) is reassuring to pregnant women and prevents unnecessary visits. The healthcare provider should remember that some women are more vigilant at fetal movement monitoring than others and therefore other methods of surveillance might be needed if the mother of the baby is less likely to comply with the fetal movement count. There are numerous studies which are trying to determine various new methods to track fetal movements while the pregnant woman is at home or work. Some methods could allow a more consistent and objective method to measuring frequency and possible strength of movements. The advance of three-dimensional ultrasound has allowed researchers to study normal movements of the fetus throughout pregnancy. This includes facial expressions and rapid eye movement (REM) during sleep. The arm movements of twins compared to singleton births are being studied and evaluated. Researchers find that fetal movement changes throughout pregnancy and can indicate normal or abnormal development. It is of note that studies have shown that obese women are able to feel fetal movement as well as women with normal body mass index (BMI).  However, due to more common maternal and fetal complications, obese women will likely notice decreased fetal movement more often than their lower BMI counterparts.

Clinical Significance

Any decrease in the perceived fetal movement should be followed up by the healthcare provider with a non-stress test. This non-invasive test can evaluate fetal movement and fetal heart rate accelerations. A reactive non-stress test must have accelerations of the fetal heart of a specific size, duration, and frequency. This includes at least three fetal heart tone (FHT) accelerations which are at least 15 beats per minute above the baseline and last at least 15 seconds, all within a 20-minute window. A non-reactive non-stress test, one that does not have the three accelerations, could indicate fetal sleep or fetal compromise, and further testing should be done. Usually, the non-stress test is first extended for a longer time to determine if the lack of accelerations was just due to fetal sleep.  If the non-stress test continues to be non-reactive, then a BPP (biophysical profile) is often completed. This is an ultrasound of the fetus which is assessing: fetal breathing movement, fetal movement of the body or limbs, fetal tone and amniotic fluid volume. If this test does not reassure the healthcare provider, then delivery of the fetus should be considered.

Fetal movement count monitoring is a low-cost and low-tech method that has the potential to prevent worsening problems with unborn babies and merits the attention of providers and pregnant women.