Uterine Tachysystole During Pregnancy – Causes, Risks and Treatment

For example, a doctor, while doing one of his normal health checkups during labor, observes that the baby has a heart condition that needs immediate attention. Now, the expected delivery date has not still arrived. The doctor may give the mother some medicines to induce labor. Rarely, such labour-inducing medications can lead to side effects resulting in tachysystole. 

However, uterine tachysystole during pregnancy does not happen solely because of medications, there are other reasons as well, such as hypertension during pregnancy and the use of epidurals during labor. 

How Common is Uterine Tachysystole During Pregnancy?

According to research that occurred to find instances of uterine tachysystole in birthing moms. In the year 2009, a total of 50,335 deliveries were recorded among 48,529 women. Among this population, it was observed that 7,567 cases of uterine tachysystole had occurred.

Further, a study on the same was published in the journal of maternal-fetal & neonatal medicine. This time, they ensured that the subjects or mothers were not taking any labour-inducing medicines. If not more, a minimum of one case of uterine tachysystole was found among 11% of these moms.

Keeping the above two studies in mind, it’s quite clear that uterine tachysystole takes place even without any labour-stimulating medicines, and is quite rare but yet not uncommon. Most mothers don’t experience this. But limited data is available to conclude the exact cause of uterine tachysystole among birthing mothers who do experience this.

Causes of Uterine Tachysystole During Pregnancy

Women who experience episodes of uterine tachysystole most likely, as per evidence, do it because of these reasons

1. Use of Labour-Stimulating Medicines

Once your baby achieves the growth they are supposed to do in the uterus, its natural response is to move downwards. They begin to move towards the birth canal. Up to this point, the lower part of the uterus is tightly closed ensuring the safety of the baby. 

Once the baby starts descending down, your cervix begins to dilate making way for the baby to come out of the birth canal.  Imagine you are putting your hand inside a rubber band, slowly. The rubber band will start to thin out and expand.

As the cervix experiences this pressure, the body understands that the baby wants to come out. So in response, it releases a hormone called oxytocin. Oxytocin, released by the pituitary gland in your brain, promotes contractions in the uterus. This is done to help the baby move to the lower portion of the uterus.

But when oxytocin is taken as a form of medicine to stimulate labour, it can lead to excessive contractions. Although rare, this can lead to excessive frequent contractions. 

2. Use of Epidural to Manage Pain

Epidural numbs the nerves, and you feel less pain from the contraction. But this medication may intervene with the natural balance of oxytocin and other hormones. Therefore, the need comes to take it from outside. As you have seen in the above case, it sometimes causes uterine tachysystole.

[Read : What Is An Epidural?]

3. Hypertension and Preeclampsia

Hypertension or high blood pressure increases the force of blood flow through the blood vessels. The blood vessels become narrow or small in width (because of the buildup of cholesterol plaque in the walls).  Because of the narrowed-down blood vessels, less space is available for blood to flow. Therefore, the heart needs to pump blood with more force to meet the requirements. 

Hence, if proper blood flow is absent, the contractions won’t happen well. In such cases, the body’s mechanism comes up with a solution – it releases more oxytocin to cope with the decreased blood flow. This is how the uterus contracts normally even in case of less blood supply to the uterus. But sometimes, this can cause excessive contractions.

Other possible causes for this condition could be 

• Labour induction 
• Long labour 
• History of smoking

Risks and Complications of Uterine Tachysystole

Frequent and intense uterine contractions are annoying to the mother. Also, it is associated with a few risks and complications.

Here are a few risks of uterine tachysystole

1. Fetal Heart Rate Irregularities

If someone steps on a pipe that is watering plants in a garden, the water flow reduces. Similarly, contractions squeeze the blood vessels for short moments that supply oxygen and nutrients to the fetus. Consequently, the heart rate drops. After a contraction is completed, the blood vessels relax, and the fetal heart rate becomes normal.

Uterine Tachysystole can squeeze these blood vessels too frequently or for too long, resulting in a drop in the fetus’s heart rate for more than normal periods. In most cases, however, the fetus doesn’t suffer any negative outcome. 

2. C-Section Delivery

Uterine tachysystole can lead to C-Section deliveries. Because it increases the risk of uterine rupture which can be a complication for both the mother and the baby. Doctors may take a quick decision to avoid frequent fetal heart rate irregularities and to ensure a healthy delivery. 

[Read : Emergency C-Sections]

How is Uterine Tachysystole Treated?

The treatment for uterine tachysystole comes into the picture only when the contractions continue to remain extreme. The healthcare provider may stop the labour-inducing medicines.

Moreover, they may also put the mother on oxygen support and on IV fluids. Your doctors may also administer medications in some cases of urgency to control the uterine contractions. Other than this, changing the mother’s position also helps. For example, the mother can lean forward or lie on one side, as per the doctor’s guidance.

Although uterine tachysystole during pregnancy is not very common, it won’t cause any harm to most mothers facing it. However, moms who are having too many contractions for too long should seek immediate medical care.

FAQ’s

1. How Many Uterine Contractions in 10 Minutes is Normal?

A normal contraction pattern during labor consists of 3 to 5 contractions occurring within a 10-minute window, and each contraction lasting between 30 to 40 seconds.

2. What Are the Maximum Uterine Contractions?

It’s safe to say that 5 contractions per 10 minutes are the maximum uterine contractions under the range of being normal.

3. How Do You Control Uterine Contractions?

Based on the urgency and need, your doctors may prescribe medicines to minimise the contractions. However, you can even try changing positions and getting comfortable to see if that helps. 

Read Also: Electronic Fetal Monitoring During Labor and Delivery