Equipments for normal delivery

For mother -

Sterile delivery pack containing - 

1. Articles for cutting and suturing an episiotomy

- Episiotomy scissors 

- Artery clamps - 3

- Tissue forceps - 1

- Needle holder - 1

- Syringe and needle for infiltration - 10 ml

2. Scissors for cutting the cord

3. Bowl for cleaning solution
4. Basin to receive placenta
5. Cotton balls
6. Gauze pieces
7. Towel to cover the hand supporting the perineum
8. Sterile gown
9. Leggings for mother
10. Apron, gloves and mask for staff

For new born -
1. Baby blanket or flannel cloths - 2
  - One to receive and dry the baby of excess secretion and another to wrap the baby.
2. Neonatal resuscitation equipment
3. Oxygen cylinder with tubing
4. Suction apparatus and mucous extraction
5. Cord clamps
6. Bulb syringe for nasal oropharyngeal suctioning of the baby

Other articles -
- Antiseptic lotion - savlon or dettol
- Suture material
- Perineal pads for mother
- Sterile gloves
- Methergin
- Lignocaine 2%

Mechanism of birth

The series of movements that occur on the head in the process of adaptation,
during its journey through the pelvis, is called mechanism of labour.
The principle movements are :-
  1. Engagement
  2. Discent
  3. Flexion
  4. Internal rotation
  5. Crowning
  6. Extension
  7. Restitution
  8. External rotation of the head and internal rotation of the shoulder
  9. Delivery of the shoulder and trunk.

Engagement -
The fetus head enters in brim (inlet) is called engagement. In primigravidae,
engagement occurs before the onset of labour while in multiparae, engagement
occurs in late first stage with the rupture of membranes.

Descent -
Provided there is no undue bony or soft tissue obstruction, descent is a continuous
process. It is slow in first stage but pronounced in second stage. It is completed
with the expulsion of the fetus. Factors facilitating are
- Uterine contraction and retraction.
- Bearing down efforts.

Flexion -
As the head meets the resistance of the birth canal during descent, full flexion is
achieved. Flexion is achieved either due to the resistance offered by the unfolding
cervix, the walls of the pelvis or by the pelvic floor.

Internal rotation -
It is a movement of great importance without which there will be no further descent.
It is probably due to slope of pelvic floor, pelvic shape and inequalities in flexibility
of component parts of the fetus. Torsion of the neck is an inevitable phenomenon
during internal rotation of head. There is no movement of the shoulders from the
oblique diameter as the neck sustains a torsion of only 1/8th of a circle.

Crowning -
After internal rotation of the head , further descent occurs until the subocciput lies
underneath the pubic arch. At this stage, the maximum diameter of the head
(biparietal diameter) stretches the vulval outlet without any recession of the
head even after the contraction is over - called ''crowning of the head''.

Extension -
Delivery of the head takes place by extension through 'couple of force' theory.
The driving force pushes the head in a downward direction while the pelvic floor
offers a resistance in the upward and forward direction. The downward and upward
forces neutralise and remaining forward thrust helping in extension.

Restitution -
It is visible passive movement of the head due to untwisting of the neck sustained
during internal rotation.

External rotation -
It is movement of rotation of the head visible externally due to internal rotation
of the shoulders.

Birth of shoulders and trunk -
After the shoulders are positioned in antero-posterior diameter of the outlet, further
descent takes place until the anterior shoulder escapes below the symphysis pubis
first. By a movement of lateral flexion of the spine, the posterior shoulder sweeps
over the perineum. Rest of the trunk is then expelled out by lateral flexion.

Fourth stage of labour

It is not included in labour process. It is only observational stage in which 
the condition of the patient is observed after the delivery of the baby. 
Pulse, blood pressure, behaviour of the uterus and any abnormal vaginal bleeding
is to be watched at least for one hour after delivery. When fully satisfied that
the general condition is good, pulse and blood pressure are steady, the uterus
is well contracted and there is no abnormal vaginal bleeding, the patient is sent
to the ward.

If the placenta is not delivered

Expulsion of placenta -
Only when the features of placental separation and its descent into the lower segment
are confirmed, the patient is asked to bear down simultaneously with the hardening of
the uterus. The raised intra-abdominal pressure is often adequate to expel the placenta. 
If the patient fails to expel. one can wait safely upto 10 minutes if there is no bleeding.
As soon as the placenta passes through the introitus, it is grasped by the hands and
twisted round and round with gentle traction so that the membranes are stripped intact.
If the membranes threaten to tear, they are caught hold of by sponge holding forceps and
in similar twisting movements the rest of the membranes are delivered.

If the spontaneous expulsion fails or is not practicable, because of delivery under 
anaesthesia, any one of the following methods can be used to expendite expulsion.

i) Controlled cord traction -
The palmar surface of the fingers of the left hand is placed (above the symphysis pubis)
approximately at the junction of upper and lower uterine segment. The body of the uterus
is pushed upwards and backwards, towards the umbilicus while by the right hand steady
tension (but not too strong traction) is given in downward and backward direction holding
the clamp until the placenta comes outside the introitus. The procedure is to be adopted
only when the uterus is hard and contracted.

ii) Fundal pressure -
The fundus is pushed downwards and backwards after placing four fingers behind the
fundus and the thumb in front using the uterus as a sort piston. The pressure must be
given only when the uterus becomes hard. If it is not, then make it hard by gentle rubbing.
The pressure is to be withdrawn as soon as the placenta passes through the introitus.
The uterus is massaged to make it hard, which facilitates expulsion of retained clots if any.
Injection of oxytocin (5-10) I.V. or methergin 0.2 mg is given intramuscularly.
Oxytocin is more stable and has lesser side effects.

Management of third stage of labour

Third stage is the most crucial stage of labour. Previously uneventful first and second
stage can become abnormal within a minute with disastrous consequences.

Principles -
To ensure strict vigilance and to follow the management guidelines strictly in practice
so as to prevent the complications, the important one being postpartum haemorrhage.

Steps of management -
Two methods of management are

• Expectant management
• Active management

1. Expectant management (traditional) -
In this management, the placental separation and its descent into the vagina are allowed to
occur spontaneously. Minimal assistance may be given for the placental expulsion if it needed.
- Constant watch is mandatory and the patient should not be left alone.
- If the mother is delivered in the lateral position, she should be changed to dorsal position to
  note features of placental separation and to assess the amount of blood loss.
- A hand is placed over the fundus -
   a) to recognise the signs of separation of placenta.
   b) to note the state of uterine activity - contraction and retraction.
   c) to detect, though rare, cupping of the fundus which is an early evidence of intervention
      of the uterus.
- Placenta is separated within minutes following birth of the baby. A watchful expectancy can
  be extended up to 15-20 minutes. In some institutions, ''no touch'' or ''hands off'' police is
  employed. The patient is expected to expel the placenta within 20 minutes with the aid of gravity.

Expulsion of placenta -
When the placenta descent into the lower uterine segment, the patient is asked to bear down
simultaneously with the hardening of the uterus. The raised intra-abdominal pressure is often
adequate to expel the placenta.

Examination of the placenta, membrane and cord -
The placenta is placed in a tray and is washed out in running tap water to remove the blood
and clots. The maternal surface is first inspected for its completeness and anomalies.
The maternal surface is covered with greyish decidua (spongy layer of decidua basalis).
Normally the cotyledons are placed in close approximation and any gap indicates a missing
cotyledon. The membranes - chorion and amnion are to be examined carefully for completeness
and presence of abnormal vessels indicative of succenturiate lobe. The amnion is shiny but the 
chorion is shaggy. The cut end of the cord is inspected for number of blood vessels. Normally,
there are two umbilical arteries and one umbilical vein.
Vulva, vagina and perineum are inspected carefully for injuries and to be repaired, if any.
The episiotomy wound is now sutured.

2. Active management of third stage -

Advantages -
- To minimise blood loss in third loss.
- To shorten the duration of third stage.

Procedures -
Inj. ergometrine 0.25 mg or methergin 0.2 mg is given intravenously following the birth of
anterior shoulder. If administered prior to this, there is chance of imprisonment of the shoulder
behind the symphysis pubis. If the placenta is not delivered, it should be delivered  by
controlled cord traction technique.

Mechanism of separation of placenta

Marked retraction reduces effectively the surface area at the placental
site to aboutits half. But as the placenta is inelastic, it can not keep pace
with such an extent of diminution resulting in its buckling. A shearing force 
is instituted between the placenta and the placental site which bring about 
its ultimate separation. The plane of separation runs through deep spongy
layer of decidua basahs so that a variable thickness of decidua covers the
maternal surface of separated placenta.

There are two way of separation of placenta.

1. Central separation - 

Detachment of placenta from its uterine attachment starts at the centre
resulting in opening up of few uterine sinuses and accumulation of blood
behind the placenta (retroplacental haematoma). With increasing contraction,
more and more detachment occurs facilitated by weight of the placenta and
retroplacental blood until whole of the placenta gets detached.

2. Marginal separation - 

Separation starts at the margin as it is mostly unsupported. With progressive
uterine contraction, more and more areas of the placenta gets separated.
Marginal separation is found mare frequently.

Mechanism of control of bleeding - 
The normal volume of blood flow through the placental site is 500-800 ml/min. 
At the placental separation, this has to be arrested within seconds to prevent
serious haemorrhage. Retraction of the oblique uterine muscle fibres in the
upper uterine segment through which tortuous blood vessels intertwin. The
resultant thickening of muscle exert pressure on the torn vessels action on
clamps thus securing a ligature action.

Events in third stage of labour

The third stage of labour comprises the phase of placental separation; its descent to
the lower segment and finally its expulsion with the membranes. The main events in
the third stage of labour are -
              a) Separation of the placenta
              b) Expulsion of the placenta and membrane

Placental separation -
After the birth of the baby, the uterus measures about 20 cm vertically and 10 cm
antero-posteriorly, the shape becomes discoid. The wall of the upper segment is much
thickened, while the thin and flabby lower segment is thrown into folds. The cavity is
much reduced to accommodate only the after-births. A shearing force is instituted 
between the placenta and the placental site which bring about its ultimate separation.

Separation of the membranes - 
The membranes which are attached loosely in the active part (upper uterine segment)
are thrown into multiple folds. Those attached to the lower segment are already
separated during its stretching. The separation is facilitated partly by uterine contraction 
and mostly by weight of the placenta as it descends down from the active part .

Expulsion of placenta - 
After complete separation of the placenta, it is forced down into the flabby lower uterine
segment or upper part of the vagina by effective contraction and retraction of the uterus.
Thereafter, it is expelled out by either voluntary contraction of abdominal muscles (bearing
down efforts) or by manipulative procedure.