Breech birth
Encyclopedia
A breech birth is the birth
of a baby from a breech presentation. In the breech presentation
the baby enters the birth canal with the buttocks
or feet
first as opposed to the normal head first presentation
.
The bottom-down position, called breech presentation, presents some hazards to the baby during the process of birth
, and the mode of delivery (vaginal versus Caesarean
) is controversial in the fields of obstetrics
and midwifery
.
Though labour and vaginal birth
are possible for the breech baby, certain fetal and maternal factors influence the safety of vaginal breech birth (see below). The majority of breech babies born in the United States are delivered by Caesarean section
.
It is postulated that the baby normally assumes a head down presentation because of the weight of the baby's head. As the mass of the fetal head is the same as that of the pelvis, it is more likely that the enlarging fetus is more and more restricted in its movements, and simply becomes entrapped. The shape of the uterus is a more likely determinant of the final fetal presentation as uterine shape anomalies are strong predictors of breech presentation and other malpresentations.
In addition to the above, breech births in which the sacrum
is the fetal denominator can be classified by the position of a fetus. Thus sacro-anterior, sacro-transverse and sacro-posterior positions all exist, of which sacro-anterior indicates an easier delivery.
to become thinner and to open. In the more common breech presentations, the baby’s bottom (rather than feet or knees) is what is first to descend through the maternal pelvis
and emerge from the vagina.
At the beginning of labour, the baby is generally in an oblique position, facing either the right or left side of the mother's back. As the baby's bottom is the same size in the term baby as the baby's head. Descent is thus as for the presenting fetal head and delay in descent is a cardinal sign of possible problems with the delivery of the head.
In order to begin the birth, internal rotation needs to occur. This happens when the mother's pelvic floor
muscles cause the baby to turn so that it can be born with one hip directly in front of the other. At this point the baby is facing one of the mother's inner thighs. Then, the shoulders follow the same path as the hips did. At this time the baby usually turns to face the mother's back. Next occurs external rotation, which is when the shoulders emerge as the baby’s head enters the maternal pelvis. The combination of maternal muscle tone and uterine contractions cause the baby’s head to flex
, chin to chest. Then the back of the baby's head emerges and finally the face
.
Due to the increased pressure
during labour and birth, it is normal for the baby's leading hip to be bruised and genitalia to be swollen
. Babies who assumed the frank breech position in utero may continue to hold their legs in this position for some days after birth.
may occur, particularly in the complete, footling, or kneeling breech. This is caused by the lowermost parts of the baby not completely filling the space of the dilated cervix. When the waters break the amniotic sac
, it is possible for the umbilical cord to drop down and become compressed. This complication severely diminishes oxygen
flow to the baby and the baby must be delivered immediately (usually by Caesarean section
) so that he or she can breathe. If there is a delay in delivery, the brain can be damaged. Among full-term, head down babies, cord prolapse is quite rare, occurring in 0.4 percent. Among frank breech babies the incidence is 0.5 percent, among complete breeches 4-6 percent, and among footling breeches 15-18 percent.
Head entrapment is caused by the failure of the fetal head to negotiate the maternal midpelvis. At full term, the fetal bitrochanteric diameter (the distance between the outer points of the hips) is about the same as the biparietal diameter (the transverse diameter of the skull) - simply put the size of the hips are the same as the size of the head. The relatively larger buttocks dilate the cervix as effectively as the head does in the typical head-down presentation. In contrast, the relative head size of a preterm baby is greater than the fetal buttocks. If the baby is preterm, it may be possible for the baby’s body to emerge while the cervix has not dilated enough for the head to emerge.
Because the umbilical cord—the baby’s oxygen supply—is significantly compressed while the head is in the pelvis during a breech birth, it is important that the delivery of the aftercoming fetal head not be delayed. The head only just fits through the pelvis, and if the arm is extended alongside the head, delivery will not occur. If this occurs, the Løvset manoeuvre may be employed, or the arm may be manually brought to a position in front of the chest. The Løvset manoeuvre involves rotating the fetal body by holding the fetal pelvis. Twisting the body such that an arm trails behind the shoulder, it will tend to cross down over the face to a position where it can be reached by the obstetrician's finger, and brought to a position below the head. A similar rotation in the opposite direction is made to deliver the other arm. In order to present the smallest diameter (9.5 cm) to the pelvis, the baby’s head must be flexed (chin to chest). If the head is in a deflexed position, the risk of entrapment is increased. Uterine contractions and maternal muscle tone encourage the head to flex. If the birth attendant pulls on the baby’s body, this action may deflex the head.
Oxygen deprivation may occur from either cord prolapse or prolonged compression of the cord
during birth, as in head entrapment. If oxygen deprivation is prolonged, it may cause permanent neurological damage or death
.
Injury
to the brain
and skull
may occur due to the rapid passage of the baby's head through the mother's pelvis
. This causes rapid decompression of the baby's head. In contrast, a baby going through labor in the head-down position usually experiences gradual molding (temporary reshaping of the skull) over the course of a few hours. This sudden compression and decompression in breech birth may cause no problems at all, but it can injure the brain. This injury is more likely in preterm babies. The fetal head may be controlled by a special two handed grip call the Mariceau-Smellie-Veit manoeuvre or the elective application of forceps. This will be of value in controlling the rate of delivery of the head and reduce decompression. Related to potential head trauma, researchers have identified a relationship between breech birth and autism
.
Squeezing the baby’s abdomen can damage internal organs. Positioning the baby incorrectly while using forceps to deliver the aftercoming head can damage the spine or spinal cord. It is important for the birth attendant to be knowledgeable, skilled, and experienced with all variations of breech birth. In the United States, because Cesarean section is increasingly being used for breech babies, fewer and fewer birth attendants are developing these skills.
Injury may occur even if a birth attendant uses appropriate interventions during labour. A majority of full-term term frank breech babies would be born without problems even without assistance. However, in a minority of cases, expert assistance is needed for the baby to be born safely. This must be placed in perspective. It is this minority that determines the safety of the choice of vaginal delivery of the breech. A fetal death rate as low as 1% might be acceptable to some societies if a greater benefit could accrue. Take a country like the United States with a population of 300 million, and a 14.14/1000 birth rate, assume a 3% breech rate, and the aforementioned 1% mortality. This would result in an annual attributable death rate from breech delivery of 1,273 babies per year. Attributable death rate implies that the deaths occurred because of the selection of vaginal delivery and not from concurrent problems, such as congenital abnormalities or prematurity.
Using hypothetical scenarios, a small study in the Netherlands found that few obstetric practitioners would attempt ECV in the presence of oligohydramnios
. A case report of treating oligohydramnios with amnioinfusion, followed by ECV, was successful in turning the fetus.
Various manoeuvres are suggested to assist spontaneous version of a breech presenting pregnancy. These include maternal positioning or other exercises. A study has shown that there is insufficient evidence as to the benefit of maternal positioning in reducing the incidence of breech presentation.
is the most common way to deliver a breech baby in the USA, Australia
, and Great Britain
. Like any major surgery
, it involves risks. Maternal mortality
is increased by a Caesarean section, but still remains a rare complication in developed countries. Third World statistics are dramatically different, and mortality is increased significantly. There is remote risk of injury to the mother's internal organs, injury to the baby, and severe hemorrhage requiring hysterectomy
with resultant infertility
.
One large study has confirmed that elective cesarean section has lower risk to the fetus and a slightly increased risk to the mother than planned vaginal delivery of the breech. However, elements of the methodology used have undergone some criticism.
Birth
Birth is the act or process of bearing or bringing forth offspring. The offspring is brought forth from the mother. The time of human birth is defined as the time at which the fetus comes out of the mother's womb into the world...
of a baby from a breech presentation. In the breech presentation
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...
the baby enters the birth canal with the buttocks
Buttocks
The buttocks are two rounded portions of the anatomy, located on the posterior of the pelvic region of apes and humans, and many other bipeds or quadrupeds, and comprise a layer of fat superimposed on the gluteus maximus and gluteus medius muscles. Physiologically, the buttocks enable weight to...
or feet
Foot
The foot is an anatomical structure found in many vertebrates. It is the terminal portion of a limb which bears weight and allows locomotion. In many animals with feet, the foot is a separate organ at the terminal part of the leg made up of one or more segments or bones, generally including claws...
first as opposed to the normal head first presentation
Cephalic presentation
A cephalic presentation is a situation at childbirth where the fetus is in a longitudinal lie and the head enters the pelvis first; the most common form of cephalic presentation is the vertex presentation where the occiput is the leading part...
.
The bottom-down position, called breech presentation, presents some hazards to the baby during the process of birth
Birth
Birth is the act or process of bearing or bringing forth offspring. The offspring is brought forth from the mother. The time of human birth is defined as the time at which the fetus comes out of the mother's womb into the world...
, and the mode of delivery (vaginal versus Caesarean
Caesarean section
A Caesarean section, is a surgical procedure in which one or more incisions are made through a mother's abdomen and uterus to deliver one or more babies, or, rarely, to remove a dead fetus...
) is controversial in the fields of obstetrics
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...
and midwifery
Midwifery
Midwifery is a health care profession in which providers offer care to childbearing women during pregnancy, labour and birth, and during the postpartum period. They also help care for the newborn and assist the mother with breastfeeding....
.
Though labour and vaginal birth
Birth
Birth is the act or process of bearing or bringing forth offspring. The offspring is brought forth from the mother. The time of human birth is defined as the time at which the fetus comes out of the mother's womb into the world...
are possible for the breech baby, certain fetal and maternal factors influence the safety of vaginal breech birth (see below). The majority of breech babies born in the United States are delivered by Caesarean section
Caesarean section
A Caesarean section, is a surgical procedure in which one or more incisions are made through a mother's abdomen and uterus to deliver one or more babies, or, rarely, to remove a dead fetus...
.
Etiology
Certain factors can encourage a breech presentation. Prematurity is likely the chief cause. Twenty five percent of fetuses are in the breech position at 32 weeks gestation; this drops to three percent at term. The increasing size of the fetus near term traps the fetus into the head down position normally. Pregnancies ending in preterm birth simply recruit more breeches before they can turn to head down. Factors predisposing to term breech presentation include:- multiple (or multifetal) pregnancy (twins, triplets or more)
- abnormal volume of amniotic fluidAmniotic fluidAmniotic fluid or liquor amnii is the nourishing and protecting liquid contained by the amniotic sac of a pregnant woman.- Development of amniotic fluid :...
: both polyhydramniosPolyhydramniosPolyhydramnios is a medical condition describing an excess of amniotic fluid in the amniotic sac. It is seen in 0.2 to 1.6% of pregnancies,,...
and oligohydramniosOligohydramniosOligohydramnios is a condition in pregnancy characterized by a deficiency of amniotic fluid. It is the opposite of polyhydramnios.-Diagnosis:Diagnosis is made by ultrasound measurement of the amniotic fluid index... - fetal anomalies: hydrocephalyHydrocephalusHydrocephalus , also known as "water in the brain," is a medical condition in which there is an abnormal accumulation of cerebrospinal fluid in the ventricles, or cavities, of the brain. This may cause increased intracranial pressure inside the skull and progressive enlargement of the head,...
, anencephalyAnencephalyAnencephaly is a cephalic disorder that results from a neural tube defect that occurs when the cephalic end of the neural tube fails to close, usually between the 23rd and 26th day of pregnancy, resulting in the absence of a major portion of the brain, skull, and scalp...
and other congenital abnormalities - uterineUterusThe uterus or womb is a major female hormone-responsive reproductive sex organ of most mammals including humans. One end, the cervix, opens into the vagina, while the other is connected to one or both fallopian tubes, depending on the species...
abnormalitiesUterine malformationA uterine malformation is a type of female genital malformation resulting from an abnormal development of the Müllerian duct during embryogenesis... - prior Caesarean sectionCaesarean sectionA Caesarean section, is a surgical procedure in which one or more incisions are made through a mother's abdomen and uterus to deliver one or more babies, or, rarely, to remove a dead fetus...
It is postulated that the baby normally assumes a head down presentation because of the weight of the baby's head. As the mass of the fetal head is the same as that of the pelvis, it is more likely that the enlarging fetus is more and more restricted in its movements, and simply becomes entrapped. The shape of the uterus is a more likely determinant of the final fetal presentation as uterine shape anomalies are strong predictors of breech presentation and other malpresentations.
Epidemiology
Researchers generally cite a breech presentation frequency at term of 3-4% at the onset of labour though some claim a frequency as high as 7%. When labour is premature, the incidence of breech presentation is higher. At 28 weeks' gestation 25% of babies are breech, and the percentage decreases approaching term (40 weeks' gestation).--Categories
There are either three or four main categories of breech births, depending upon the source:- Frank breech - the baby's bottom comes first, and his or her legs are flexed at the hip and extended at the knees (with feet near the ears). 65-70% of breech babies are in the frank breech position.
- Complete breech - the baby's hips and knees are flexed so that the baby is sitting crosslegged, with feet beside the bottom.
- Footling breech - one or both feet come first, with the bottom at a higher position. This is rare at term but relatively common with premature fetuses.
- Kneeling breech - the baby is in a kneeling position, with one or both legs extended at the hips and flexed at the knees. This is extremely rare, and is excluded from many classifications.
In addition to the above, breech births in which the sacrum
Sacrum
In 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...
is the fetal denominator can be classified by the position of a fetus. Thus sacro-anterior, sacro-transverse and sacro-posterior positions all exist, of which sacro-anterior indicates an easier delivery.
Process of breech birth
As in labour with a baby in a normal head-down position, uterine contractions typically occur at regular intervals and gradually cause the cervixCervix
The cervix is the lower, narrow portion of the uterus where it joins with the top end of the vagina. It is cylindrical or conical in shape and protrudes through the upper anterior vaginal wall...
to become thinner and to open. In the more common breech presentations, the baby’s bottom (rather than feet or knees) is what is first to descend through the maternal pelvis
Pelvis
In human anatomy, the pelvis is the lower part of the trunk, between the abdomen and the lower limbs .The pelvis includes several structures:...
and emerge from the vagina.
At the beginning of labour, the baby is generally in an oblique position, facing either the right or left side of the mother's back. As the baby's bottom is the same size in the term baby as the baby's head. Descent is thus as for the presenting fetal head and delay in descent is a cardinal sign of possible problems with the delivery of the head.
In order to begin the birth, internal rotation needs to occur. This happens when the mother's pelvic floor
Pelvic floor
The pelvic floor or pelvic diaphragm is composed of muscle fibers of the levator ani, the coccygeus, and associated connective tissue which span the area underneath the pelvis. The pelvic diaphragm is a muscular partition formed by the levatores ani and coccygei, with which may be included the...
muscles cause the baby to turn so that it can be born with one hip directly in front of the other. At this point the baby is facing one of the mother's inner thighs. Then, the shoulders follow the same path as the hips did. At this time the baby usually turns to face the mother's back. Next occurs external rotation, which is when the shoulders emerge as the baby’s head enters the maternal pelvis. The combination of maternal muscle tone and uterine contractions cause the baby’s head to flex
Flexion
In anatomy, flexion is a position that is made possible by the joint angle decreasing. The skeletal and muscular systems work together to move the joint into a "flexed" position. For example the elbow is flexed when the hand is brought closer to the shoulder...
, chin to chest. Then the back of the baby's head emerges and finally the face
Face
The face is a central sense organ complex, for those animals that have one, normally on the ventral surface of the head, and can, depending on the definition in the human case, include the hair, forehead, eyebrow, eyelashes, eyes, nose, ears, cheeks, mouth, lips, philtrum, temple, teeth, skin, and...
.
Due to the increased pressure
Pressure
Pressure is the force per unit area applied in a direction perpendicular to the surface of an object. Gauge pressure is the pressure relative to the local atmospheric or ambient pressure.- Definition :...
during labour and birth, it is normal for the baby's leading hip to be bruised and genitalia to be swollen
Swelling (medical)
In medical parlance, swelling is the transient enlargement or protuberance in the body and may include tumors. According to cause, it may be congenital, traumatic, inflammatory, neoplastic or miscellaneous....
. Babies who assumed the frank breech position in utero may continue to hold their legs in this position for some days after birth.
Risks
Umbilical cord prolapseCord prolapse
Umbilical cord prolapse happens when the umbilical cord precedes the fetus' exit from the uterus. It is an obstetric emergency during pregnancy or labor that imminently endangers the life of the fetus. Cord prolapse is rare...
may occur, particularly in the complete, footling, or kneeling breech. This is caused by the lowermost parts of the baby not completely filling the space of the dilated cervix. When the waters break the amniotic sac
Amniotic sac
The amniotic sac is the sac in which the fetus develops in amniotes. It is a tough but thin transparent pair of membranes, which hold a developing embryo until shortly before birth. The inner membrane, the amnion, contains the amniotic fluid and the fetus. The outer membrane, the Chorion,...
, it is possible for the umbilical cord to drop down and become compressed. This complication severely diminishes oxygen
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...
flow to the baby and the baby must be delivered immediately (usually by Caesarean section
Caesarean section
A Caesarean section, is a surgical procedure in which one or more incisions are made through a mother's abdomen and uterus to deliver one or more babies, or, rarely, to remove a dead fetus...
) so that he or she can breathe. If there is a delay in delivery, the brain can be damaged. Among full-term, head down babies, cord prolapse is quite rare, occurring in 0.4 percent. Among frank breech babies the incidence is 0.5 percent, among complete breeches 4-6 percent, and among footling breeches 15-18 percent.
Head entrapment is caused by the failure of the fetal head to negotiate the maternal midpelvis. At full term, the fetal bitrochanteric diameter (the distance between the outer points of the hips) is about the same as the biparietal diameter (the transverse diameter of the skull) - simply put the size of the hips are the same as the size of the head. The relatively larger buttocks dilate the cervix as effectively as the head does in the typical head-down presentation. In contrast, the relative head size of a preterm baby is greater than the fetal buttocks. If the baby is preterm, it may be possible for the baby’s body to emerge while the cervix has not dilated enough for the head to emerge.
Because the umbilical cord—the baby’s oxygen supply—is significantly compressed while the head is in the pelvis during a breech birth, it is important that the delivery of the aftercoming fetal head not be delayed. The head only just fits through the pelvis, and if the arm is extended alongside the head, delivery will not occur. If this occurs, the Løvset manoeuvre may be employed, or the arm may be manually brought to a position in front of the chest. The Løvset manoeuvre involves rotating the fetal body by holding the fetal pelvis. Twisting the body such that an arm trails behind the shoulder, it will tend to cross down over the face to a position where it can be reached by the obstetrician's finger, and brought to a position below the head. A similar rotation in the opposite direction is made to deliver the other arm. In order to present the smallest diameter (9.5 cm) to the pelvis, the baby’s head must be flexed (chin to chest). If the head is in a deflexed position, the risk of entrapment is increased. Uterine contractions and maternal muscle tone encourage the head to flex. If the birth attendant pulls on the baby’s body, this action may deflex the head.
Oxygen deprivation may occur from either cord prolapse or prolonged compression of the cord
Umbilical cord
In placental mammals, the umbilical cord is the connecting cord from the developing embryo or fetus to the placenta...
during birth, as in head entrapment. If oxygen deprivation is prolonged, it may cause permanent neurological damage or death
Death
Death is the permanent termination of the biological functions that sustain a living organism. Phenomena which commonly bring about death include old age, predation, malnutrition, disease, and accidents or trauma resulting in terminal injury....
.
Injury
Injury
-By cause:*Traumatic injury, a body wound or shock produced by sudden physical injury, as from violence or accident*Other injuries from external physical causes, such as radiation injury, burn injury or frostbite*Injury from infection...
to the brain
Human brain
The human brain has the same general structure as the brains of other mammals, but is over three times larger than the brain of a typical mammal with an equivalent body size. Estimates for the number of neurons in the human brain range from 80 to 120 billion...
and skull
Human skull
The human skull is a bony structure, skeleton, that is in the human head and which supports the structures of the face and forms a cavity for the brain.In humans, the adult skull is normally made up of 22 bones...
may occur due to the rapid passage of the baby's head through the mother's pelvis
Pelvis
In human anatomy, the pelvis is the lower part of the trunk, between the abdomen and the lower limbs .The pelvis includes several structures:...
. This causes rapid decompression of the baby's head. In contrast, a baby going through labor in the head-down position usually experiences gradual molding (temporary reshaping of the skull) over the course of a few hours. This sudden compression and decompression in breech birth may cause no problems at all, but it can injure the brain. This injury is more likely in preterm babies. The fetal head may be controlled by a special two handed grip call the Mariceau-Smellie-Veit manoeuvre or the elective application of forceps. This will be of value in controlling the rate of delivery of the head and reduce decompression. Related to potential head trauma, researchers have identified a relationship between breech birth and autism
Autism
Autism is a disorder of neural development characterized by impaired social interaction and communication, and by restricted and repetitive behavior. These signs all begin before a child is three years old. Autism affects information processing in the brain by altering how nerve cells and their...
.
Squeezing the baby’s abdomen can damage internal organs. Positioning the baby incorrectly while using forceps to deliver the aftercoming head can damage the spine or spinal cord. It is important for the birth attendant to be knowledgeable, skilled, and experienced with all variations of breech birth. In the United States, because Cesarean section is increasingly being used for breech babies, fewer and fewer birth attendants are developing these skills.
Injury may occur even if a birth attendant uses appropriate interventions during labour. A majority of full-term term frank breech babies would be born without problems even without assistance. However, in a minority of cases, expert assistance is needed for the baby to be born safely. This must be placed in perspective. It is this minority that determines the safety of the choice of vaginal delivery of the breech. A fetal death rate as low as 1% might be acceptable to some societies if a greater benefit could accrue. Take a country like the United States with a population of 300 million, and a 14.14/1000 birth rate, assume a 3% breech rate, and the aforementioned 1% mortality. This would result in an annual attributable death rate from breech delivery of 1,273 babies per year. Attributable death rate implies that the deaths occurred because of the selection of vaginal delivery and not from concurrent problems, such as congenital abnormalities or prematurity.
Factors influencing the safety
- Type of breech presentation - the frank breech has the most favorable outcomes in vaginal birth, with many studies suggesting no difference in outcome compared to head down babies. (Some studies, however, find that planned caesarean sections for all breech babies improve outcome. The difference may rest in part on the skill of the doctors who delivered babies in different studies.) Complete breech presentation is the next most favorable position, but these babies sometimes shift and become footling breeches during labour. Footling and kneeling breeches have a higher risk of cord prolapse and head entrapment.
- ParityParity (medicine)In biology, parity is a technical term that refers to the number of times a female has given birth to a fetus.It can lead to some ambiguity for events occurring between 20 and 24 weeks, and for multiple pregnancies.-Enumeration:...
- Parity refers to the number of times a woman has given birth before. If a woman has given birth vaginally, her pelvis has "proven" it is big enough to allow a baby of that baby's size to pass through it. However, a head-down baby's head often molds (shifts its shape to fit the maternal pelvis) and so may present a smaller diameter than the same size baby born breech. Research on the issue has been contradictory as far as whether vaginal breech birth is safer when the mother has given birth before, or not. - Fetal size in relation to maternal pelvicPelvisIn human anatomy, the pelvis is the lower part of the trunk, between the abdomen and the lower limbs .The pelvis includes several structures:...
size - If the mother's pelvis is roomy and the baby is not large, this is favorable for vaginal breech delivery. However, prenatal estimates of the size of the baby and the size of the pelvis are unreliable. - Hyperextension of the fetal headHeadIn anatomy, the head of an animal is the rostral part that usually comprises the brain, eyes, ears, nose and mouth . Some very simple animals may not have a head, but many bilaterally symmetric forms do....
- this can be evaluated with ultrasound. Less than 5% of breech babies have their heads in the "star gazing" position, face looking straight upwards and the back of the head resting against the back of the neck. Caesarean delivery is absolutely necessary, because vaginal birth with the baby's head in this position confers a high risk of spinal cord trauma and death. - MaturityFetal developmentPrenatal or antenatal development is the process in which a human embryo or fetus gestates during pregnancy, from fertilization until birth. Often, the terms fetal development, foetal development, or embryology are used in a similar sense.After fertilization the embryogenesis starts...
of the Baby - Premature babies appear to be at higher risk of complications if delivered vaginally than if delivered by caesarean section. - Progress of Labor - A spontaneous, normally progressing, straightforward labor requiring no intervention is a favorable sign.
- Second twinsTWINSTwo Wide-Angle Imaging Neutral-Atom Spectrometers are a pair of NASA instruments aboard two United States National Reconnaissance Office satellites in Molniya orbits. TWINS was designed to provide stereo images of the Earth's ring current. The first instrument, TWINS-1, was launched aboard USA-184...
- If a first twin is born head down and the second twin is breech, the chances are good that the second twin can have a safe breech birth. - Birth attendant's skill (and experience with breech birth) - The skill of the doctor or midwife and the number of breech births previously assisted is of crucial importance. Many of the dangers in vaginal birth for breech babies come from mistakes made by birth attendants.
Turning the baby to avoid breech birth
There are many methods which have been attempted with the aim of turning breech babies, with varying degrees of success:- External cephalic versionExternal cephalic versionExternal cephalic version is a process by which a breech baby can sometimes be turned from buttocks or foot first to head first. It is usually performed after about 37 weeks...
where a midwife or doctor turns the baby by manipulating the baby through the mother's abdomen. ECV has a success rate between 40 - 70% depending on practitioner. The fetal heart is monitored after the turn attempt, usually in the context of an institutional protocol. Studies show that turning the baby at term (after 36 weeks) is effective in reducing the number of babies born in the breech position. Complications from external cephalic version are rare. Studies have also shown that attempting to turn the baby prior to this point has no impact on the presentation at term.
Using hypothetical scenarios, a small study in the Netherlands found that few obstetric practitioners would attempt ECV in the presence of oligohydramnios
Oligohydramnios
Oligohydramnios is a condition in pregnancy characterized by a deficiency of amniotic fluid. It is the opposite of polyhydramnios.-Diagnosis:Diagnosis is made by ultrasound measurement of the amniotic fluid index...
. A case report of treating oligohydramnios with amnioinfusion, followed by ECV, was successful in turning the fetus.
Various manoeuvres are suggested to assist spontaneous version of a breech presenting pregnancy. These include maternal positioning or other exercises. A study has shown that there is insufficient evidence as to the benefit of maternal positioning in reducing the incidence of breech presentation.
Breech birth versus Caesarean section
Caesarean sectionCaesarean section
A Caesarean section, is a surgical procedure in which one or more incisions are made through a mother's abdomen and uterus to deliver one or more babies, or, rarely, to remove a dead fetus...
is the most common way to deliver a breech baby in the USA, Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
, and Great Britain
Great Britain
Great Britain or Britain is an island situated to the northwest of Continental Europe. It is the ninth largest island in the world, and the largest European island, as well as the largest of the British Isles...
. Like any major surgery
Surgery
Surgery is an ancient medical specialty that uses operative manual and instrumental techniques on a patient to investigate and/or treat a pathological condition such as disease or injury, or to help improve bodily function or appearance.An act of performing surgery may be called a surgical...
, it involves risks. Maternal mortality
Death
Death is the permanent termination of the biological functions that sustain a living organism. Phenomena which commonly bring about death include old age, predation, malnutrition, disease, and accidents or trauma resulting in terminal injury....
is increased by a Caesarean section, but still remains a rare complication in developed countries. Third World statistics are dramatically different, and mortality is increased significantly. There is remote risk of injury to the mother's internal organs, injury to the baby, and severe hemorrhage requiring hysterectomy
Hysterectomy
A hysterectomy is the surgical removal of the uterus, usually performed by a gynecologist. Hysterectomy may be total or partial...
with resultant infertility
Infertility
Infertility primarily refers to the biological inability of a person to contribute to conception. Infertility may also refer to the state of a woman who is unable to carry a pregnancy to full term...
.
One large study has confirmed that elective cesarean section has lower risk to the fetus and a slightly increased risk to the mother than planned vaginal delivery of the breech. However, elements of the methodology used have undergone some criticism.
See also
- Asynclitic birthAsynclitic birthAn asynclitic birth or asynclitism refers to the position of a baby in the uterus such that the head is tilted to the side, causing the fetal head to no longer be in line with the birth canal. Most asynclitism corrects spontaneously in the progress of normal labor...
, another abnormal birth position - ChildbirthChildbirthChildbirth is the culmination of a human pregnancy or gestation period with the birth of one or more newborn infants from a woman's uterus...
- PregnancyPregnancyPregnancy refers to the fertilization and development of one or more offspring, known as a fetus or embryo, in a woman's uterus. In a pregnancy, there can be multiple gestations, as in the case of twins or triplets...
- Uterine RuptureUterine ruptureUterine rupture is a potentially catastrophic event during childbirth by which the integrity of the myometrial wall is breached. In an incomplete rupture the peritoneum is still intact. With a complete rupture the contents of the uterus may spill into the peritoneal cavity or the broad ligament...