What is breech presentation?
The majority of babies at full term are positioned in the uterus with their head down. This enables the baby to be born head first through the vagina. Alternatively, approximately 3-4% of full term babies are in the breech presentation (Shanahan & Gray 2022). Breech presentation means the baby’s buttocks, feet or both are positioned to be born first, before the baby’s head.
Why do some babies stay in the breech presentation until the end of pregnancy?
For most babies, there is no clearly defined reason for why they have remained in the breech presentation until the end of pregnancy. Some possible factors which can influence a baby’s presentation include:
- Preterm birth (less than 37 weeks gestation)
- Too much amniotic fluid (polyhydramnios)
- Too little amniotic fluid (oligohydramnios
- Multiples (twins or triplets)
- Length of umbilical cord
- Placenta previa
- Abnormal size or shape of the uterus
- Other uterine abnormalities (fibroids)
Different types of breech positions
Source: SOGC 2022
- Frank Breech: Legs directed upwards with feet by baby’s head
- Complete Breech: Legs folded at the knee with feet at the level of the buttocks, the buttocks would be born first
- Footling Breech: One or both feet extend downwards so the legs would emerge before the buttocks
External Cephalic Version (ECV)
While there are several methods for attempting to spontaneously turn a baby into a head down position (see Spinning Babies below), some babies will require assistance to be turned externally. During an external cephalic version, an experienced health care practitioner will apply pressure externally to the baby through the abdomen of the client. The pressure is applied to the baby in such a way that the baby will ideally do a summersault forward into a head down position. Approximately 58% of ECVs are successful in turning baby to the head down position (Shanahan & Gray 2022).
Example of ECV (SOCG 2022)
Factors associated with the increased success of ECVs: having had at least one baby already, baby lying across the abdomen (transverse or oblique presentation), complete breech position, adequate amniotic fluid, unengaged presenting part.
Factors associated with the decreased success of ECVs: first baby, the cervix is already dilated, estimated weight of baby is less than 2,500g, anterior placenta, decreased amniotic fluid, membranes already ruptured, maternal obesity, frank breech position, engaged presenting part.
Potential complications of ECV
ECVs are an intervention and due to the manipulation of the baby and the uterus there is a risk of the following complications:
- Prelabour rupture of membranes
- Changes in the fetus’s heart rate
- Placental abruption
- Preterm labour
Due to these risks ECVs (by local guidelines) are always performed in a hospital setting, with close monitoring before, during and after the ECV. ECVs are also only performed when there is an obstetric team and OR available for an emergency c-section should it be necessary.
If an ECV is unsuccessful and the baby remains in a breech presentation, the majority of clients in Ontario will proceed to have a planned c-section. Vaginal breech birth is only available with an experienced healthcare provider who is willing to manage a client’s care.
For any questions, feel free to view the additional resources below or discuss with your midwife options regarding your care.