What causes a baby to be breech?
Signs of a breach presentation
- Hard ballotable head palpable in the uterine fundus (the top of the uterus)
- Baby kicking down in the pelvis
- Soft presenting part palpable below the navel
- Easier to listen for baby's heartbeat above the navel of the mother
- Soft presenting part with no sutures in vaginal examination
What does breech mean?
During pregnancy a breech presentation is when the baby's bottom is the presenting part in the mother’s pelvis instead of the baby's head. During the first 30 weeks of pregnancy, the babies have enough room to change positions as they like. Around 28 weeks of pregnancy, 15% of babies are breech, and as the weeks go by, more and more of them turn around for the more common head presentation. At 34 weeks only 6% of babies are breech and at term of 40 weeks, only 3% are still breech.
So if you are less than 34 weeks you don't have to worry, your baby will most likely turn on its own and half of babies that are breech at 34 weeks will turn on their own before term.
How the baby's legs lie is categorized in these definitions of breech presentation:
- Frank breech is a breech presentation where the legs are extended and lie beside the head. This is the most common type of breech presentation as 70% of breech babies are in this position. Very common with primaparas (first time mothers).
- Complete or flexed breech presentation is similar to frank breech but the knees are flexed and the feet are close to the baby's bottom. It is the second most common breech presentation (25-29%) and is more common with multiparas (women who have given birth before) and is 25-29% of all breech babies.
- Footling presentation is rare, one or both legs are the presenting part in the pelvis.
- Knee presentation is a variation of a complete breech presentation when the knee is the presenting part.
What causes breech position?
In most cases, there is not one specific reason for why that baby is breech at term. Usually it is associated with a couple of reasons that have effect on the movement of the baby in the uterus.
Causes related to the mother
- Polyhydramnios- excessive amniotic water in the amniotic sack, common for mothers who have diabetes or gestational diabetes. The baby has more room to move than usual and therefore can be in any position late in the pregnancy
- Too little amniotic fluid so the baby gets stuck in one position and doesn’t have the room to change.
- Multiple pregnancies, for example the second twin to get born is often in a breech position.
- Mothers pelvis has an abnormal shape or is to tight
- Grand multiparas, mothers of 5 or more children are prone to have babies in breech position because the muscles in the abdomen and uterus do not have the same support as before.
- Abnormally shaped uterus
- Cancer or myomas in the uterus
- Older age mothers
- Drug abuse can cause low muscle tone in the baby
Causes related to the baby
- Preterm labor, baby hasn't turned yet.
- Small baby has more room to change positions
- Fetal defects
- Short umbilical cord can restrain movements
What to do about it ?
Early in the pregnancy, it’s not something to worry about since most of the babies turn themselves before term. After week 34-36 of pregnancy, there are methods that can help turn the baby.
There are three main option when a baby is still breach in late pregnancy
- External version, done by an OB/GYN or a trained midwife. It is a procedure where the doctor/midwife will try to maneuver the baby from the outside. This can be uncomfortable and there are risk factors involved. The good outcome is a baby in a good position, and normal birth possible.
- Breach delivery is a possibility, after an assessment of the exact position of the baby and measurements of the woman's pelvis and if the midwife or doctor delivering the baby has been trained in breach deliveries.
- Elective c-section, when external version has not worked and breach delivery is not considered an option.