In this position, the babys chin is tucked onto its chest, so that the smallest part of its head will be applied to the cervix first. The position is usually "Left Occiput Anterior", or LOA. Occasionally, the baby may be "Right Occiput Anterior", or ROA. Face presentation
Factors that predispose to face presentation are prematurity, macrosomia, anencephaly and other malformations, cephalopelvic disproportion, and polyhydramnios. In an uncomplicated face presentation duration of labor is not altered. Perinatal losses with face presentation occur with traumatic version and extraction and midforceps procedures Duff indicates that the prevalence of face presentations is about 1/500–600., while Benedetti et al. found it to be 1/1,250 term deliveries.Face presentations are classified according to the position of the chin (mentum):

Left Mento-Anterior (LMA), Left Mento-Posterior (LMP), Left Mento-Transverse (LMT)
Right Mento-Anterior (RMA), Right Mento-Posterior (RMP), Right Mento-Transverse (RMT)

Brow presentation
While some consider the brow presentation as an intermediate stage towards the face presentation, others disagree. Thus Bhal et al. indicated that both conditions are about equally common (1/994 face and 1/755 brow positions), and that prematurity was more common with face while postmaturity was more common with brow positions. Oskie presentation
The Oskie presentation is similar to the Occipito-Anterior position, where the baby is head down, facing the spine, with back on the ventral side of the uterus; however, in this position, while the torso is aligned with the mothers longitudinal axis, the legs of the fetus are extended straight along the frontal axis of the mother, as if the baby is creating a right angle with its body.
A vertex presentation is the ideal situation for a vaginal birth, although occiput posterior positions tend to proceed more slowly, often requiring intervention in the form of forceps, vacuum extraction, or Cesarean section. In a large study, a majority of brow presentations were delivered by Cesarean section, however, because of postmaturity, factors other than labour dynamics may have played a role. Most face presentations can be delivered vaginally as long as the chin is anterior; there is no increase in fetal or maternal mortality. Mento-posterior positions cannot be delivered vaginally in most cases (unless rotated) and are candidates for Cesarean section in contemporary management. References


== External links ==