Gmail Log in Email: External Cephalic Version (ECV)

In a normal pregnancy, the baby settles in a cephalic (head down) position by the last few weeks of pregnancy, ready for delivery ^[1]. But sometimes, the baby may remain in a feet-down position (breech baby) ^[2] even as your labor starts, often requiring a c-section. In such cases, the External cephalic version or ECV may come useful, letting you consider a natural delivery ^[3].

What is and external cephalic version (ECV)

An external cephalic version or ECV is a medical procedure for turning your baby into a proper head-down position from a breech or transverse presentation by applying pressure on a certain point in your belly ^[4].

ECV procedure: Turning a breech baby

The main purpose of attempting an ECV is to give the mother a chance to have a natural vaginal birth. Before an ECV, you may be given some tocolytic medication (labor repressants) to relax the uterine muscles and prevent contractions during the procedure ^[4]. The doctor then places his hands on your abdomen, one above the place where the baby’s head is and another below his buttocks and pushes the baby to make him rotate ^[5]. In some cases, it may need more than one attempt to successfully turn the baby. You may be offered a local anesthesia, especially if ECV is attempted multiple times.

External Cephalic Version

Your baby’s position, as well as his heart rate is closely monitored at all time ^[6] so the process can be stopped the moment there is the smallest sign of fetal distress (such as his heart rate dropping suddenly) ^[5]. Due to this reason, an ECV is always performed at a hospital where the doctor may monitor the baby easily using methods and equipments like ultrasound, and an emergency c-section may be arranged in case of a possible threat to the mother or the baby ^[7]. The amniotic fluid level is also measured prior to the procedure while Rh-negative women are given an Rh immune globulin injection to avoid complications ^[8].

When is an ECV attempted

No specific gestational age has been set as ideal for attempting an ECV. Although, studies have shown it to reduce the chances of a breech presentation at birth when performed before term (weeks 33-36), it is usually performed in or after week 37 ^{[7, 9]} as your baby may still have time to turn on his own before that ^[10]. It is associated with a considerable success rate when performed in up to 42 weeks ^[11].

Women with their first pregnancy are usually offered an ECV at or after the 36th week while those with a second or subsequent pregnancy may have the procedure after week 37 ^[11].

Does an external cephalic version hurt

Most women describe the process as uncomfortable to moderately painful, but bearable due to its short duration ^[18]. About 5% of women undergoing ECV have reported severe pain during the attempt ^[11]. Analgesic medication may be necessary to carry on the process in some cases. The version may be stopped if the mother experiences excessive pain as it might indicate some complications ^[14]. It has been found that a successful ECV causes less pain than an unsuccessful one ^[19].

When is external cephalic version avoided

Your doctor may check your medical history and examine your baby to see if a cephalic version should be contraindicated. Common factors to avoid it include:

Having a suspected placental complication, such as a previa or an abruption, in this pregnancy or history of one in a previous pregnancy

Severe high blood pressure or preeclampsia ^[12]

Having experienced any vaginal bleeding within the past week ^[13]

Having an abnormally shaped uterus (e.g. a bicornuate uterus) ^[14]

Low levels of amniotic fluid or any other complication associated with the fluid or sac, such as ruptured membranes

Tocolytic medications contraindicated for the mother due to some heart disorder or some other health condition ^[5]

History of a cesarean section or needing a c-section in current pregnancy due to some other complications ^[15]

Carrying twins

Ultrasound or some other test detecting any sign of fetal distress (e.g. irregular heart rate) ^[16]

Suspecting some fetal growth restriction or anomaly ^[18]

Are there any risks of an external cephalic version (ECV)

Studies show ECV to be possibly safe, being associated with a small chance of some serious complications.

Maternal complications

It rarely leads to any complications, but in any case, the following complications should be considered before opting for the procedure:

Placental abruption ^[20]

Your waters breaking early (premature rupture of membranes) ^[21]

Uterine rupture (rare) ^[22]

Beginning of labor (in about 1% of the cases) ^[15]

Women who opt for an ECV have a higher chance of requiring a cesarean delivery than those with a spontaneously occurring cephalic presentation (study). Due to this reason, it is usually preferable to wait for as long as possible to give the baby a chance to turn into position on his own before attempting a version ^[23].

Fetal complications

Multiple studies have shown no increase in the risk of intrauterine fetal death within 24 hours of successfully turning a breech baby. The fetal heart rate is monitored immediately after the procedure to check for any abnormalities. There are usually no complications, but EVC may sometimes lead to:

Changes in the fetal heartbeat detected on the monitor ^[24]

The umbilical cord getting squeezed, reducing the oxygen and blood flow to the fetus ^[5] (increasing the risk of birth defects and problems such as brain damage)

Nuchal cord ^[29]

Fetomaternal hemorrhage (fetal blood cells getting into the mother’s blood-stream) ^[25]

An emergency c-section is necessary in around 0.50% of all ECV attempts, commonly because of signs of fetal distress or placental bleeding ^{[8, 13]}.

External cephalic version success rate

It is successful in over 50% of cases ^[26] in reducing the chances of a vaginal breech delivery as well as a c-section (study review), with the exact success rates depending on the medical history of the mother as well as the health of the baby ^[13]. About 90% of transverse babies have been turned successfully using this method ^[8].

C-section is one of the principle causative factors for various maternal complications after childbirth. So, ECV also contributes to reducing the risk of such problems ^[4]. However, even after a successful attempt, your baby may turn back into a breech position (in less than 5% cases ^[27]), requiring a cesarean birth ^[6]. Your doctor may also schedule a second attempt if possible.

Factors contributing to a better chance of success

Having had a baby before ^[26]

The baby being situated high up in the uterus and not engaged in the pelvis ^[6]

Having proper amniotic fluid levels around the baby

Having a posterior placenta (located at the posterior side of the uterus) ^[16]

The mother having proper BMI and body weight

A complete breech presentation of the baby

Routine use of tocolytics has also been shown by studies to increase the success rate of ECV when performed at term. Epidural anesthesia has been shown to contribute to a better chance of success as well (study).

When to call the doctor

Talk to your doctor to understand the care and restrictions necessary following the procedure. Watch out for the following warning signs after an ECV: