Fetal movement during pregnancy: baby's first kicks

Feeling your baby move is one of the most thrilling moments throughout the entire pregnancy. What do you need to know about it? This amazing moment happens during pregnancy for every woman. At first, it's easy to mistake it for bowel movements or the tensing of the abdominal muscles, but over time, the movements become stronger and more distinct. By the 8th week of pregnancy, the fetus develops nerve endings and the first muscle bundles responsible for motor activity. The intensity and activity of these movements are diagnostic criteria for the health of the unborn child. Back in the last century, diagnostic tests were developed that use fetal movements to detect hypoxia and fetoplacental insufficiency. But how do you accurately interpret these results? What factors influence the baby's movements inside the mother's womb?

The First Fetal Movements

The nervous system of the embryo begins to form at the 6th week of pregnancy. By the 7th to 8th week, involuntary movements are recorded, but at this stage, the embryo is still too small (its length is only about 0.6–0.9 inches), so the woman does not feel these movements. By the 10th to 11th week, the motor regulation centers in the brain are forming. That's when the first voluntary muscle contractions occur.

After the placenta finishes developing in the first trimester, the fetus is in "free float" in the amniotic fluid, which protects it from infectious, temperature, and mechanical factors. It can push off from the walls of the uterus on its own, but due to its size and limited strength, these nudges are not felt by the pregnant woman.

A turning point comes between the 16th to 22nd week. The future baby reaches a length of about 7–8.7 inches, and its weight sharply increases to between 5–10.5 ounces. It begins to respond to external stimuli (sound, mechanical).

What Affects the Timing of Feeling the First Fetal Movement

Expectant mothers start feeling their baby's movements at different stages of pregnancy. Why does this happen? Several factors influence this:

1. Body constitution characteristics. Women who are overweight or have excessive body mass tend to feel movements later, around the 21st to 22nd week. Fat deposits in the abdominal area act as a cushion for the baby's movements. Slimmer pregnant women usually notice movements earlier, around the 18th to 19th week.
2. For a woman's first pregnancy, the movements are generally felt later than in subsequent pregnancies. This is because the tone of the abdominal wall decreases after childbirth, and the sensation of fetal movements becomes familiar to the woman. Therefore, during her second pregnancy, she might notice them about two weeks earlier.
3. The number of fetuses. In a multiple pregnancy, a mom can start feeling movements as early as the 16th week (or even sooner).
4. The mother's anticipation. If a pregnant woman is eagerly awaiting her baby's movements and constantly paying attention to her body, she might notice them a bit earlier.

What Fetal Movement Feels Like

Fetal movement is detected by mechanoreceptors located in the walls of the abdominal cavity and on internal organs. That's why its initial symptoms are nonspecific. Women often describe the sensation of movement as a "fluttering butterfly" or a "swimming fish" in their belly. Also, the baby's movements can be mistaken for intestinal activity.

From the 22nd week, the movement becomes more noticeable. It feels like pressure or "kicks" in different areas of the abdomen, with the intensity increasing over time. In the second trimester, the baby can freely change its position in the womb. When it turns, you might notice a change in the external shape of the belly. Sometimes, you can even see a footprint.

In the third trimester of pregnancy, the fetus grows to about 16–20 inches in length and assumes a more stable position. Its kicks can be painful, as it often hits the bladder, liver, or stomach with its limbs.

Factors Influencing Fetal Movement

While in the womb, a baby can respond to various external and internal stimuli. Their motor activity depends on the following factors:

1. Time of day. Many pregnant women note that their baby is most active during the evening or nighttime hours.
2. Connection to eating. Often, fetal movement increases after the mother has eaten, or conversely, when she's hungry.
3. Familiar voices. Experiments have confirmed that from the second trimester, a fetus can recognize voices it frequently hears. These can either soothe or, conversely, stimulate them.
4. Background noise. Sudden sounds stimulate movement.
5. The mother's psycho-emotional state. During stress, excitement, fear, or depression, the baby may experience either reduced or increased movement.
6. The mother's uncomfortable position and physical activity. The baby tends to move more when at rest or if they're in an uncomfortable position.

Baby Movement Norms

The activity of a baby in the womb gradually increases. By the 20th week, on average, they make 160–180 movements, with the peak activity observed between the 28th and 30th weeks – 500–600 movements. In the third trimester, the number of movements slightly decreases due to the limited space available. Naturally, the mom only feels the most powerful kicks of the fetus.

When is it advisable to start monitoring the frequency of the baby's movements? Experts recommend doing this starting from the 28th week. Women are given special forms with charts where they can record their observations. The medical staff must definitely explain to the pregnant woman how to do this correctly, in which situations she should not panic, and when it's necessary to consult a doctor.

At what point should you be concerned if there are no movements? Practically all patients feel fetal movements by the end of the 22nd week. But if this hasn’t happened, it's better to reach out to your OB-GYN.

Fetal Movement and Cardiotocography

Cardiotocography is a non-invasive ultrasound technique used to monitor a fetus's heart rate. The normal range for this measurement is 120–160 beats per minute. It's routinely performed in the second and third trimesters of pregnancy following an examination by a gynecologist.

The motor-cardial reflex, which appears in the fetus from the 28th week, holds significant diagnostic value. During a standard cardiotocography session, there's simultaneous monitoring of the baby's movement. The expectant mother is given a remote with a button to press whenever she feels the baby move. At these moments, the heart rate on the ultrasound increases by 15–30 beats per minute for more than 10 seconds.

If the baby remains calm throughout the examination, the pregnant woman might be asked to walk around the room a bit.

The absence of the motor-cardial reflex indicates the development of fetoplacental insufficiency, which is accompanied by impaired blood supply to the fetus.

Kick Count Chart

In gynecological practice, a kick count chart is used, where the pregnant woman logs her observations of the fetus's movement activity. There are several types of these charts:

1. The Pearson Chart (the "Count to Ten" method) is the most commonly used. Observations are conducted from 9 AM to 9 PM. The expectant mother needs to record the time of the 10th movement (for example, 12:30 PM) in a special chart.
2. The Cardiff Method. The woman chooses the time for observation herself (but also 12 hours) and notes when the 10th movement occurs, the time of which is recorded on a special form.
3. The Sadovsky Technique. After dinner, the pregnant woman lies on her left side (these factors contribute to increased motor activity). Within four hours, she should feel more than 10 separate kicks.

When using the Pearson or Cardiff methods, the expectant mother can go about her daily activities, but without excessive physical exertion.

Warning Signs

There are several situations when a pregnant woman needs to immediately seek medical help:

• no fetal movement for more than six hours;
• sudden significant decrease in the strength and frequency of fetal movements;
• sharp abdominal pain, bleeding, or pus-like discharge from the genital tract against a backdrop of reduced fetal activity;
• premature rupture of membranes or the onset of contractions.

If a decrease in fetal movement is detected during cardiotocography, and there is an absence of the motor-cardiac reflex, the pregnant woman is advised to be hospitalized in the pathology department, where additional examinations (blood tests, Doppler ultrasound, amniocentesis, and others) are conducted, and supportive therapy is prescribed. Since the goal is to preserve the lives of both the mother and the child, the possibility of premature delivery (via cesarean section) is discussed.

When There's No Need to Worry

Sometimes, a baby might swallow amniotic fluid, which triggers rhythmic contractions of the diaphragm (hiccups) that mom can feel. This is totally safe.

There's no need to freak out if you notice a lack of active movements for a few hours. The little one might just be sleeping. Their daily rhythm often doesn't match up with mom's.

If they're super active at night and keeping you from getting some rest, it's better to adjust to the baby's schedule. A few hours of daytime sleep can help you fully recharge.

During a first pregnancy, it's common to experience active fetal movements that can cause significant discomfort or pain for the expectant mother. However, there's no risk of injury or issues with the digestive or urinary systems. This doesn't indicate that premature birth is on the horizon. Pregnant women are advised to find a comfortable position (lying on their side), wear loose clothing, and use pillows and orthopedic mattresses.