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Diameters of superior aperture of lesser pelvis (female). fetus over bony pelvis in normal presentation for birth Linea Nigra Leopold's Maneuvers Leopolds' maneuvers are used to determine the orientation of the fetus through abdominal palpation. Using two hands and compressing the maternal abdomen, a sense of fetal direction is obtained (vertical or transverse). The sides of the uterus are palpated to determine the position of the fetal back and small parts. The presenting part (head) is palpated above the symphysis and degree of engagement is determined The fetal occipital prominence determined. Head Palpation Doppler Normal Labor Is the process by which a single full term living viable fetus is expelled from the natural passage within reasonable hours. in which the fetus presents by the vertex and which terminates naturally without artificial aid and without complications. Calculation of the date of labor: A calculation based on the date of the last menstrual period is the method in common use. It is the most accurate method. The average duration of pregnancy is ten lunar months, forty weeks or 280 days from the 1st day of the last menstruation. The onset of the labor: Is recognised by: (1) painful uterine contractions (labor pains). (2) Blood stained cervical mucus ‘the show'. (3) Commencing dilatation of the cervical os . (4) Formation of the bag of fore-water. Symptoms and Signs • Cervix not dilated Stage False labor/ Phase Not in labor Table C-8 Diagnosis of stage and phase of labour a • Cervix dilated less than 4 cm First Latent • Cervix dilated 4–9 cm • Rate of dilatation typically 1 cm per hour or more • Fetal descent begins First Active • Cervix fully dilated (10 cm) • Fetal descent continues • No urge to push Second Early (non-expulsive) • Cervix fully dilated (10 cm) • Presenting part of fetus reaches pelvic floor • Woman has the urge to Second Late(expulsive) Effacement and dilatation of the cervix Abdominal palpation for descent of the fetal head Vaginal examination vaginal examination may be used to assess descent by relating the level of the fetal presenting part to the ischial spines of the maternal pelvis . Note: When there is a significant degree of caput or moulding, assessment by abdominal palpation is more useful than assessment by vaginal exam. Assessing descent of the fetal head by vaginal examination.0 station is at the level of the ischial spine . Presentation and position Determine the presenting part The most common presenting part is the vertex of the fetal head. If the vertex is not the presenting part, it is called malpresentation. If the vertex is the presenting part, use landmarks on the fetal skull( occiput) to determine the position of the fetal head in relation to the maternal pelvis. Landmarks of the fetal skull Determine the position of the fetal head The fetal head normally engages in the maternal pelvis in an occiput transverse position, with the fetal occiput transverse in the maternal pelvis. With descent, the fetal head rotates so that the fetal occiput is anterior in the maternal pelvis (occiput anterior positions), Failure of an occiputotransverse position to rotate to an occiputo- anterior position should be managed as an occiputo- posterior position An additional feature of a normal presentation is a well-flexed vertex with the occiput lower in the vagina than the sinciput. Well-flexed vertex Assessment of progress of labor Once diagnosed, progress of labor is assessed by: -Measuring changes in cervical effacement and dilatation during the latent phase. -Measuring the rate of cervical dilatation and fetal descent during the active phase. -Assessing further fetal descent during the second stage. Plot a simple graph of cervical dilatation (centimetres) on the vertical axis against time (hours) on the horizontal axis. Vaginal examinations Vaginal examinations should be carried out at least once every 4 hours during the first stage of labor and after rupture of the membranes. At each vaginal examination, record the following: -Color of amniotic fluid; - Cervical dilatation; -Descent of the presenting part (can also be assessed abdominally). Cervical dilatation Assessing descent of the fetal head by vaginal examination.0 station is at the level of the ischial spine . In the second stage of labor, perform vaginal examinations once every hour. USING THE PARTOGRAPH The WHO partograph has been modified to make it simpler and easier to use. The latent phase has been removed and plotting on the partograph begins in the active phase when the cervix is 4 cm dilated. The modified WHO Partograph Labor pains Regular, frequent, uterine contractions which lead to progressive dilatation of the cervix. Braxton-Hicks contractions Uterine contractions occurring prior to the onset of labor. They are normal and can be demonstrated early in the middle trimester of pregnancy. These innocent contractions can be painful, regular, and frequent, although they usually are not effective. While the uterine contractions of labor are usually painful, they are sometimes mildly painful, in the early stages of labor. Occasionally, they are painless. Cervical dilatation alone does not confirm labor, since many women will demonstrate some dilatation (1-3 cm) for weeks or months prior to the onset of labor. Thus, labor will be determined by observing the patient over time and demonstrating progressive cervical changes, in the presence of regular, frequent, painful uterine contractions. Latent Phase Labor The first stage can be divided functionally into two phases: the latent phase and the active phase. Latent phase of labor (also known as prodromal labor) precedes the active phase of labor. Women in latent phase labor Are less than 4 cm dilated. Have regular, frequent contractions that may be painful. The contractions wax and wane Cervix dilate only very slowly Can usually talk or laugh during their contractions May find this phase of labor lasting days or longer Active Phase Labor Active phase labor is a time of rapid change in cervical dilatation, effacement, and station. Active phase labor lasts until the cervix is completely dilated. Women in active phase labor: Are at least 4 cm dilated. Have regular, frequent contractions that are usually moderately painful. Demonstrate progressive cervical dilatation of at least 1.2-1.5 cm per hour. Usually are not comfortable with talking or laughing during their contractions Progress of Labor For a woman experiencing her first baby, labor usually lasts about 12-14 hours. In multigravida, labor is generally quicker, lasting about 6-8 hours. These averages are only approximate, and there is considerable variation from one woman to the next, and from one labor to the next. During labor, the cervix dilates (opens) and effaces (thins). This process has been likened to the process of pulling a turtleneck sweater over your head. The collar opens (dilates) to allow your head to pass through, and also thins (effaces) as your head passes through. The process of dilatation and effacement occurs for mechanical &biochemical reasons. The force of the contracting uterus naturally seeks to dilate and thin the cervix. However, the cervix to be respond to these forces requires it to be "ready.“ The process of readying the cervix on a cellular level usually takes place over days to weeks preceding the onset of labor (ripening). Descent means that the fetal head descends through the birth canal. The "station" of the fetal head describes how far it has descended through the birth canal. This station is determined relative to the maternal ischial spines( bony prominences on each side of the maternal pelvic sidewalls). "0 Station" means that the top of the fetal head descended through the birth canal just to the level of the maternal ischial spines. -This means that the fetal head is "fully" engaged (or "completely engaged"), because the widest portion of the fetal head has entered the opening of the birth canal (the pelvic inlet). - If the fetal head not reached the ischial spines, this is indicated by negative numbers, such as -2 (the top of the fetal head is 2 cm above the ischial spines). -If the fetal head has descended further than the ischial spines, this is indicated by positive numbers, such as +2 (the top of the head is 2 cm below the ischial spines). Negative numbers above -3 indicate the fetal head is unengaged (floating). Positive numbers beyond +3 (+4 or +5) indicate that the fetal head is crowning and about to deliver. Primigravida demonstrate deep engagement (0 or +1) days to weeks prior to the onset of labor. Multiparous woman not engage below -2 or -3 until they are in labor, and nearly completely dilated. Uterine Contractions The onset of labor may be sudden or gradual, and is defined as regular uterine activity in the presence of cervical dilatation. During a contraction the long muscles of the uterus contract, starting at the top of the uterus and working their way down to the bottom (Fundal dominence). At the end of the contraction, the muscles relax to a state shorter than at the beginning of the contraction. This draws the cervix up over the baby's head. Each contraction dilates the cervix until it becomes completely dilated (10+ cm in diameter). gradual onset with slow cervical change towards 3 cm (just over 1 inch) dilation is referred to as the "latent phase". A woman is said to be in "active labor" when contractions have become regular in frequency (3-4 in 10 minutes) and about 60 seconds in duration. The powerful contractions are accompanied by cervical effacement and dilation greater than 3 cm. The labor may begin with a rupture of the amniotic sac, the paired amnion and chorion( rupture of bag of fore water). . In the "transition phase" from 8 cm–10 cm of dilation, the contractions often come every two minutes & lasting 70–90 seconds. The duration of labor varies widely, but averages some 13 hours for primiparae 8 hours for multiparae. Electronic fetal monitoring Cervical dilatation assessed at every vaginal examination and marked with a cross (X). Begin plotting on the partograph at 4 cm. Alert line: A line starts at 4 cm of cervical dilatation to the point of expected full dilatation at the rate of 1 cm per hour. Action line: Parallel and 4 hours to the right of the alert line. Descent assessed by abdominal palpation: At 0/5, the sinciput (S) is at the level of the symphysis pubis. Bl p: Record every 4 hours and mark with arrows. Temperature: Record every 2 hours. Protein, acetone and urine volume: Record every time urine is passed STAGES OF NORMAL LABOUR Normal Labour is the process of expulsion of a mature foetus with the placenta and membranes. It is divided into three stages: Stage I lasts from the onset of labor to full dilatation of the cervix. In primigravida this stage lasts for about 10 to 12 hours. In multipara it lasts from 6 to 8 hours. A typical childbirth will begin the onset of the first stage of labour The First Stage is divided into three phases: Phase I: is the longest and least painful phase of labour. It starts from the time when the cervix first starts to dilate to the time when the cervix is 4 cm dilated. It is also called 'Latent phase' of labor. It can last for days and can occur with only the mildest discomfort to the pregnant woman. Phase II: This is a more active phase of labor. The cervix dilates from 4 cm to 8 cm during this phase. The contractions are more painful , of longer duration and come more regularly. It is also called the 'middle phase ' of labour. Phase III: During this phase, the cervix dilates from 8 cm to 10 cm, the cervix is fully dilated and the baby's head can come out of the uterus safely and easily. This phase is also called the 'transition phase' of labour since it marks the transition of the First stage to the Second stage. Stage II : lasts from the full dilatation of the cervix to the expulsion of the baby. In a first pregnancy, it lasts for about 1- 2 hour, in subsequent pregnancies, it lasts for about ½ hour. This stage is a stage when the baby's head is travelling down the vaginal canal to be delivered. The contractions are very painful, appearing to produce continuous pain. The second stage of labor starts at the end of the first stage when the cervix is fully dilated to 10 cm. In the Mother: Contraction and Retraction Painful, involuntary contractions as well as retractions occur in the uterine muscles. Contraction of the Accessory Muscles: As the second stage starts, the abdominal muscles and diaphragm contract forcefully to expel the fetus (bearing down pains). The woman in labor holds her breath after taking a deep inspiration thereby fixing the diaphragm in a lower position and contracts the abdominal muscles This action increases the intra- abdominal pressure, compressing the uterus and helps in increasing the expulsive force. in the later part of second stage, the urge and the pressure becomes involuntary and synchronises with the uterine contractions. Changes in the Surrounding Organs: As the fetus moves into the vagina it dilating the vaginal cavity. The structures in front ( the bladder and the urethra ) pushed upwards and forwards. This results in inability to pass urine by woman in labor. The structures behind the uterus ( the rectum, the anus and the perineum ) displaced downwards and backwards. So the woman gets a desire to pass stool , the perineum becomes stretched and thinned out. The anus opens up as the head descends In the Baby: The baby undertakes a series of movements and changes in position during its passage through the vaginal canal to the vaginal outlet. In a normal labor, the baby faces the mothers back and delivers in this position (with the face towards the mother's back). Engagement: means that the largest transverse diameter of the fetal head is at the level of the smallest diameter of the mother's pelvis (ischial spine). Descent with Flexion: The baby descends deeper into the mother's pelvis. At the same time, the flexion of its body ( the arms folded in front of the chest, the legs tucked in front of the abdomen, and the chin touching the chest wall )increases, so that the overall size of the baby becomes smaller and can fit into the pelvis. When the head of the baby reaches the lowest point of the pelvic floor, it presses against the perineum causing it to bulge slowly. The head of the baby is now seen at the vaginal opening. Initially, the head retracts back when the uterine contraction decreases. Later, the head remains at the opening even when there is no uterine contraction. This is called 'Crowning‘. Descent: As the fetal head engages and descends, it assumes an occiput transverse position because it is the widest pelvic diameter available for the widest part of the fetal head. Flexion: While descending, the head flexes so the fetal chin is touching the chest. The occipital (posterior fontanel) slides into the center of the birth canal and the anterior fontanel becomes more remote and difficult to feel. Fetal position remains occiputotransverse. Internal Rotation: With further descent, the occiput rotates anteriorly and the fetal head assumes an oblique orientation. In some cases, the head may rotate completely to the occipitoanterior position. Extension: The curve of the hollow of the sacrum favors extension of the fetal head as further descent occurs. This means that the fetal chin is not touching the fetal chest External Rotation: The shoulders rotate into an oblique or frankly anterio-posterior orientation with further descent. This encourages the fetal head to return to its transverse position. This is also known as Restitution . Delivery by Extension: As the fetal head reaches the maternal symphysis pubis it hitches under the bone. The pressure by the uterine contractions causes the neck of the baby to get extended . The forehead appears first, then the eyes and nose and lastly the mouth as the neck extends more and more. The baby's nose and mouth is suctioned of any secretions at this time to clear up the respiratory tract and help the baby to breathe properly. Normal Delivery Traction Childbirth Stage 2 Vaccum extraction Forceps Delivery of the Shoulders: Once the head is out, the contractions may or may not decrease in intensity for some time. Then the contractions increase once again, the anterior shoulder (the shoulder just under the symphysis pubis) hitches under the bone and the posterior shoulder (the shoulder towards the rectum) is delivered first. The body of the baby now slides smoothly out of the vaginal canal. The delivery of the baby signifies the end of the second stage and the beginning of the 'Third Stage' Steps of management of the second stage of labor : The principles of management of this stage are: (a) to ensure birth of a healthy baby (b) to prevent damage to the maternal tissues. Labor monitoring – The maternal pulse and blood pressure are recorded. Fetal heart rate is counted and recorded after every contraction. Uterine contractions are checked. Position during delivery – The standard position for the delivery of the baby is the lithotomy position (the patient lies on her back, legs flexed on the hips, knees flexed and spread wide apart). Cleansing of the vulva & the surrounding parts with sterile solutions. Catheterisation of the bladder is done if the patient cannot pass urine. The patient is encouraged to bear down with every pain. Crowning of the head - The head is said to be crowned when it distends the vaginal opening, without retracting inside the vagina after the episode of pain is over. Episiotomy –doctors prefer to do an episiotomy when the head is crowned to prevent injury to the perineum. Episiotomy increases the size of the vaginal opening. The head is delivered slowly, preventing sudden extension of the head at the neck.This can cause injury and tearing of the maternal perineum. The perineum is supported by the left palm of the doctor during delivery of the head. After the head is delivered, the eyes are swabbed with sterile cotton swabs, mouth and nostrils are aspirated and a hand passed over the neck to check for the presence of cord around the neck. Next pains bring on the delivery of shoulders and trunk. Baby is held in a head down position while the cord is clampedThe baby is then handed over to the paedetrician. Third stage: placenta Breastfeeding during and after the third stage In this stage, the uterus expels the placenta (afterbirth). Breastfeeding the baby will help to cause this. The mother normally loses less than 500 mL of blood. Blood loss will be greater if the umbilical cord is used to tug on the placenta. It is essential that the placenta be examined to ensure that it was expelled whole. Remaining parts can cause postpartum bleeding or infection. Stage III lasts from the birth of the baby to the expulsion of the placenta and the membranes. It lasts for about 15 - 20 minutes in both first and later pregnancies. The third stage is comparatively less painful and is characterised by a gush of bleeding at the time the placenta separates The uterus contracts to become a As soon as the baby is delivered, The uterus firm globular organ reaching up to the umbilicus •Through the vagina, the cervical os is seen to become partially closed. •The baby's umbilical cord is seen snaking out of the os towards the vaginal opening. An injection of ergometrine just after the baby is delivered to stimulate the uterus to contract better. This helps to prevent any excess bleeding. Signs that the placenta is beginning to separate: A sudden gush of blood Lengthening of the visible portion of the umbilical cord. The uterus, which is usually soft and flat immediately after delivery, becomes round and firm. The uterus, the top of which is usually about half-way between the pubic bone and the umbilicus, seems to enlarge and approach the umbilicus. As the placenta separates, the woman will again feel painful uterine cramps. As the placenta descends through the birth canal, she will again feel the urge to bear down and push out the placenta. If the placenta is not promptly expelled, this is called "retained placenta" and it should be manually removed. After delivery of the placenta, the uterus normally contracts firmly, closing off the open blood vessels which supplied the placenta,without this contraction rapid blood loss will occur. To encourage the uterus to firmly contract, oxytocin 10 mIU IM can be given after delivery. Breast feeding the baby or nipple stimulation will cause the mother's pituitary gland to release oxytocin internally, causing similar, but milder effects. simple way to encourage firm uterine contraction is uterine massage. Massaging the uterus often causes the uterus to contract Oxytocin usually is given IV to stimulate uterine contractions.