Breech baby: what is it and how is the turning maneuver done?
The inversion maneuver is a medical procedure that can be done in the hospital to try to turn the fetus in the belly. Here’s what it is, how long it takes, what the success rate is, and what the alternatives are.
There are several techniques for making the fetus turn in the belly when it is in the breech position (with the bottom or feet facing the bottom of the uterus). One of these is fetal reversal maneuver , also called external cephalic version (ECV) or external maneuver reversal (RME).
Most breech babies will naturally turn over by 36 to 37 weeks of pregnancy , so that their head faces down in preparation for birth. About 3 or 4 out of 100 children remain breech .
There are higher risks of complications during delivery for babies who are in the breech position. For this reason, elective cesarean section is generally proposed when the fetus is in this position at term of pregnancy.
Why does the baby stay in the breech position?
There is not always a specific reason why the fetus is breech, but there are some factors that make it more likely , such as:
- low placenta;
- first pregnancy;
- anomalies of conformation of the uterus;
- twin pregnancy;
- too much or too little amniotic fluid around the baby (polyhydramnios/oligohydramnios).
What happens if the fetus is in the breech position?
Breech presentation is common in early pregnancy. On the other hand, when the position is maintained at the end of gestation (and ascertained by ultrasound), caesarean section is generally proposed , which represents the safest option in this situation.
However, the caesarean section involves specific risks for mother and child. For this reason, many International Scientific Societies recommend offering the reversal maneuver to all women with a fetus in breech presentation and an uncomplicated singleton pregnancy, when there are no contraindications to the procedure, so that they can face labor with the fetus in cephalic (ie head down) presentation.
What is the turning maneuver?
This is a procedure to try to turn the fetus in the womb (fetal reversal), which is done in a hospital.
The maneuver is usually proposed at 37 weeks of gestation , but can be performed from 36 weeks until early labor, as long as the water has not yet broken.
Preparation
Before proceeding with the turning of the fetus, an ultrasound is performed to evaluate the amniotic fluid and the position of the placenta. Then, a slow venous infusion of tocolytic drug (a muscle relaxant that prevents the uterus from contracting) is given to the woman .
What is it and how long does it last
The reversal of the breech fetus by external maneuver is performed under ultrasound control , with the woman in a semi-reclining position.
The gynecologist exerts a slight pressure on the maternal abdomen, to guide the fetus to perform a sort of “somersault” and orient its head downwards, in the direction of the vaginal canal.
The procedure lasts a few minutes, the discharge is the same day, after having re-checked all the parameters of fetal well-being.
Is the reversal maneuver painful?
Turning the breech fetus for external maneuvers can cause discomfort, but shouldn’t hurt . If you experience pain, it is important to inform your doctor.
Does it always work?
The success rate varies in the different cases from 30% to 80%. Influence outcomes: ethnicity, previous pregnancies, uterine tone, amniotic fluid volume, engagement of the foot (buttocks of the fetus) in the maternal pelvis, and use of tocolysis.
On average, the reversal maneuver is successful in about 60% of cases.
In case of failure of the procedure, a second attempt could be proposed , depending on the circumstances.
Very rarely (1% of cases) the child may return to the breech position after the maneuver.
What if the fetus doesn’t turn over?
If breech revolution is unsuccessful, an elective cesarean section is usually scheduled around the 39th week of pregnancy .
In fact, vaginal breech birth is not recommended in most cases, because it exposes mother and child to higher risks.
In some selected cases (e.g. second breech twin, pregnancies subsequent to the first) it is possible to request a breech birth via the vaginal route . This option, however, is only feasible at specific referral centers .
When is the reversal maneuver contraindicated?
The maneuver is contraindicated in case of:
- low placenta or abnormal placental insertion
- fetal abnormalities
- Presence of vaginal bleeding in the last 7 days
- abnormalities of the uterus
- reduced amniotic fluid
- water break
- labor already started
- twin pregnancy
What are the risks?
Breech reversal for external maneuvers is a low-risk procedure and complications are rare.
Its safety has been documented by two systematic reviews, i.e. two studies in which the researchers analyzed all the scientific literature published on the subject.
In the first review (44 studies published between 1990 and 2002) the following complications were found :
- temporary changes in fetal heart rate (5.7%)
- persistent pathological cardiotocograph traces (0.37%)
- vaginal bleeding (0.47%)
- placental abruption (0.12%).
In addition, emergency caesarean sections were performed in only 0.43% of all cephalic versions and a perinatal mortality of 0.16% was recorded.
The American College of Obstetricians and Gynecologists (ACOG) also reports the following complications:
- rupture of membranes before delivery
- preterm birth.
The second systematic review (11 studies) found no adverse outcomes (stillbirth, uterine rupture, abruptio placenta, rupture of membranes or cord prolapse, onset of labor within 24 hours).
In any case, you should call or go to the hospital if you have any of the following signs or symptoms after the reversal maneuver:
- bleeding
- abdominal pain
- contractions
- decreased fetal movements
Are there other ways to get a breech baby to turn around?
In addition to the external cephalic version, there are other more or less documented suggestions and techniques to obtain the revolution of the breech fetus.
Some suggest performing specific exercises 2-3 times a day , for about 10 minutes. The goal is to disengage the baby from the pelvis and give him more room to turn around.
There is no solid evidence to support these methods, but several moms have reported positive experiences.
Another twisting technique is moxibustion , which comes from traditional Chinese medicine.
A small number of clinical studies have shown that it works in 50-80% of cases, but currently there is still no solid evidence of its effectiveness.
Moxibustion is performed by specialized personnel. It consists of gently burning a “moxa stick” containing a soft and woolly Chinese herb called “artemisia” and bringing it close to a particular area of the little finger of the woman, to stimulate it with heat.
Other “natural” techniques for turning the breech baby are rebozo massage or acupuncture . However, these procedures have no documented effectiveness.
In any case, the gynecologist or midwife will explain the pros and cons of each technique and provide risk and benefit assessments, so that we can decide together how to proceed.
Kathryn Barlow is an OB/GYN doctor, which is the medical specialty that deals with the care of women's reproductive health, including pregnancy and childbirth.
Obstetricians provide care to women during pregnancy, labor, and delivery, while gynecologists focus on the health of the female reproductive system, including the ovaries, uterus, vagina, and breasts. OB/GYN doctors are trained to provide medical and surgical care for a wide range of conditions related to women's reproductive health.