Uterine Tachysystole (Excessively Frequent Contractions) During Pregnancy

When you’re pregnant, you can’t wait for the moment to meet your little one. In your last leg of pregnancy, you might worry about contractions, but also wait for it with the hope that they dilate your cervix enough to allow the baby to descend to the birth canal.

But contractions are quite tricky; they might make you wonder if they are a sign of false labour or real labour. Furthermore, if you have too many contractions, you will want to know if that’s normal or not. Let’s understand what happens when a woman has abnormal or excessive contractions, also referred to as uterine tachysystole.

What Is Uterine Tachysystole?

Normally, contractions during labour may last for 60-90 seconds. The term uterine ‘tachysystole’ was adopted in 2013 to describe the condition where one experiences around 5 contractions in a span of 10 minutes when in labour. It is the condition where a woman in labour experiences excessively frequent or intense contractions.

It commonly occurs in situations where certain labour-stimulating medication such as oxytocin is given. The medication may provide the woman with the hormone oxytocin, which stimulates the contractions in the uterus during labour. Oxytocin is thus vital to labour and delivery, and it may be administered in its synthetic form. However, an adverse reaction or incorrect dosage can lead to uterine tachysystole.

Tachysystole can cause severe pain and discomfort to the mother, have effects on the umbilical cord and affect the child’s health. Due to tachysystole, the child will not receive the necessary supply of oxygen from the placenta, interfering with the development of the baby in a healthy manner.

How Common Is Tachysystole?

The research on uterine tachysystole is fairly limited. However, it is a commonly observed condition. As per the research paper of the American College of Obstetricians and Gynecologists, among 50,335 deliveries, 7,567 instances of uterine tachysystole were observed. Tachysystole usually occurs in women who have been administered labour stimulating medication.

Causes of Tachysystole While Pregnant

While there is no conclusive research to determine the causes of uterine tachysystole, it is believed that there are certain factors that increase the likeliness of the condition. These conditions are:

• using labour stimulating medication like misoprostol or oxytocin. Studies have shown that the use of oxytocin increases the chances of experiencing uterine tachysystole by two times.
• Using epidural to manage pain during labour.
• Induction of labour through medication causes tachysystole because labour stimulants tend to make the contractions longer and more frequent. Incorrect administration of these medicines can result in tachysystole.
• Hypertension
• Preeclampsia

Risks and Complications

Uterine tachysystole is not inherently dangerous, but it poses several risks to the health of the baby if it is not managed properly, causing significant birth injuries. It has been associated with fetal heart rate issues, reduced fetal oxygenation, placental abruption, and the increased likelihood of having to stay in the neonatal intensive care unit.

1. Changes in Fetal Heart Rate and Oxygen Supply

As per the report published in the Americal Journal of Obstetrics and Gynaecology, uterine tachysystole heart rate issues in the fetus are common, but they don’t necessarily indicate an adverse outcome for the baby. The umbilical cord is the source of oxygen and blood for the baby, and during contractions, this flow tends to reduce or stop. The period between contractions is therefore important to keep the flow going. When the contractions become excessively frequent and intense, there is not enough time for the placenta to relax, reducing oxygen supply to the fetus and decelerating its heart rate. The supply of oxygen is critical to the baby’s life, and tachysystole may result in asphyxia leading to brain injury, hypoxic-ischemic encephalopathy, or seizure disorders. The baby may also suffer from fetal acidosis, which means that the acid levels in the brain increase, causing brain injuries like cerebral palsy.

2. Uterine Rupture

A severe case of uterine tachysystole can result in a uterine rupture. This means that the fetus may be expelled from the womb into the mother’s abdomen, posing severe risks to the life of the baby and its mother. Uterine rupture can result in severe blood loss and its related complications for the mother. And for the baby, it will hinder oxygen supply and cause asphyxia, cerebral palsy, hypoxic-ischemic encephalopathy, fetal acidosis, or other such complications.

3. C-Section Birth

As per a study published in the Journal of Maternal-Fetal & Neonatal Medicine, it was found that due to the heart rate issues that the fetus has to face during uterine tachysystole, a woman’s chances of having a C-section birth may increase. This also means that their baby will be in need of being placed in the neonatal intensive care unit.

How Is Tachysystole Treated?

Uterine tachysystole should be managed and treated in an effective manner to prevent any life-altering critical consequences to the mother or baby.

• If labour-stimulating medication is being used, the medical practitioner should ensure that they closely monitor the condition of the fetus so that they can identify any complications as and when they arrive. They should monitor the oxygen levels, hydration, changes in positions, and even consider medical intervention where necessary.
• If a woman has previously suffered from tachysystole or has been experiencing excessively frequent contractions, her medical records should be examined so that the best course of action can be determined.
• If the mother begins to show signs of tachysystole, the administration of labour-inducing drugs should be stopped immediately. The medical practitioner should not wait till the baby also begins to exhibit symptoms.
• The woman should change her position with support and lie in a lateral position. Provide the mother with sufficient oxygen and increase her dosage of IV fluids if necessary.
• If there has been a uterine rupture and a C-section delivery is necessary, medications for fetal resuscitation should be administered to prevent any permanent damage to the fetus.

Uterine tachysystole can be detrimental to the health of the mother and the life of the baby if it is not managed adequately. The impact that it has on the fetus is critical and life-altering, and therefore, it must be diagnosed and treated in time.

Also Read:

Irritable Uterus During Pregnancy
Irritable Bowel Syndrome (IBS) While Pregnant
Heartburn in Pregnancy