Position (Obstetrics)
Encyclopedia
In obstetrics
, position is the orientation of the fetus
(baby) in the womb, identified by the location of the presenting part
of the fetus relative to the pelvis of the mother. Conventionally, it is the position assumed by the fetus before the process of birth, as the fetus assumes various positions and postures during the course of childbirth
.
Obstetrics
Obstetrics is the medical specialty dealing with the care of all women's reproductive tracts and their children during pregnancy , childbirth and the postnatal period...
, position is the orientation of the fetus
Fetus
A fetus is a developing mammal or other viviparous vertebrate after the embryonic stage and before birth.In humans, the fetal stage of prenatal development starts at the beginning of the 11th week in gestational age, which is the 9th week after fertilization.-Etymology and spelling variations:The...
(baby) in the womb, identified by the location of the presenting part
Presentation (Obstetrics)
In obstetrics, the presentation of a fetus about to be born refers to which anatomical part of the fetus is leading, that is, is closest to the pelvic inlet of the birth canal. According to the leading part, this is identified as a cephalic, breech, or shoulder presentation...
of the fetus relative to the pelvis of the mother. Conventionally, it is the position assumed by the fetus before the process of birth, as the fetus assumes various positions and postures during the course of childbirth
Childbirth
Childbirth is the culmination of a human pregnancy or gestation period with the birth of one or more newborn infants from a woman's uterus...
.
Positions
Depending upon which part of the fetus is expected to be delivered first (fetal presentation), there are many possible positions:- Vertex presentation with longitudinal lie:
| Name | Abb. | Description |
|---|---|---|
| Left occipitoanterior | LOA | occiput Occiput The occiput is the anatomical term for the posterior portion of the head, in insects the posterior part of those head capsule.-Clinical significance:Trauma to the occiput can cause a basilar skull fracture.... Occiput is the prominence of the back of the head, as against the buttocks, is close to the vagina (hence known as vertex presentation) faces anteriorly (forward with mother standing) and towards left. This is the most common position and lie. |
| Right occipitoanterior | ROA | occiput faces anteriorly and towards right. Less common than LOA, but not associated with labor complications. |
| Left occipitoposterior | occiput faces posteriorly (behind) and towards left. | |
| Right occipitoposterior | ROP | occiput faces posteriorly and towards right. |
| Occipitoanterior | occiput faces anteriorly (absolutely straight without any turning to any of the sides) | |
| Occipitoposterior | occiput faces posteriorly (absolutely straight without any turning to any of the sides) | |
| Left occipitotransverse | LOT | occiput faces left |
| Right occipitotransverse | ROT | occiput faces right |
- Breech presentation with longitudinal lie:
- Left sacrumSacrumIn vertebrate anatomy the sacrum is a large, triangular bone at the base of the spine and at the upper and back part of the pelvic cavity, where it is inserted like a wedge between the two hip bones. Its upper part connects with the last lumbar vertebra, and bottom part with the coccyx...
anterior (LSA)—the buttocks, as against the occiput of the vertex presentation, like close to the vagina (hence known as breech presentation), which like anteriorly and towards the left. - Right sacrum anterior (RSA)—the buttocks face anteriorly and towards the right.
- Left sacrum posterior (LSP)—the buttocks face posteriorly and towards the left.
- Right sacrum posterior (RSP)—the buttocks face posteriorly and towards right.
- Sacrum anterior (SA)—the buttocks face anteriorly.
- Sacrum posterior (SP)—the buttocks face posteriorly.
- Shoulder presentationShoulder presentationA shoulder presentation refers to a malpresentation at childbirth where the baby is in a transverse lie , thus the leading part is an arm, shoulder, or the trunk...
with transverse lie are classified into four types, based on the location of the scapulaScapulaIn anatomy, the scapula , omo, or shoulder blade, is the bone that connects the humerus with the clavicle ....
(shoulderblade); note: this presentation needs to be delivered by cesarean section.
- Left scapula-anterior (LSA)
- Right scapula-anterior (RSA)
- Left scapula-posterior (LSP)
- Right scapula-posterior (RSP)
See also
- Child birth
- Fetal relations
- PresentationPresentation (Obstetrics)In obstetrics, the presentation of a fetus about to be born refers to which anatomical part of the fetus is leading, that is, is closest to the pelvic inlet of the birth canal. According to the leading part, this is identified as a cephalic, breech, or shoulder presentation...