Клиника и ведение родовNormal course and management of

labour

Planes and dimensions of small pelvis

Pelvic floor muscles

Location of pelvic floor muscles during fetal ejection

First period of labour

• I (first) – dilating stage of labor – from the beginning of labour contractions to full (10 cm) dilation of the orifice of uterus (period of dilatation), duration of the I delivery period in primiparas is 10-14 hours, in multiparas it is twice shorter (5-7 hours);

Second period of labour

• II (second) – expulsive stage – from full dilation of the external orifice of uterus to expulsion of fetus (period of expulsion), duration of the II delivery period is 2 hours in primiparas, 1 hour in multiparas;

Third period of labour• III (third) – placental stage (expulsion of afterbirth, placental

birth) – from fetus delivery to placental expulsion (period of placental expulsion). Delivery ends with expulsion of afterbirth. Duration of the III delivery period is 30 minutes.

Delivery duration

Group Delivery durationIn primiparas I period 10-14 hours

II period – up to 2 hours

III period – up to 30 minutes

Total 12-16 hoursIn multiparas I period 5,5-7 hours

II period – up to 1 hour

III period – up to 30 minutes

Total 6-8 hours

First period of delivery • The first period of labor begins with regular contractions and

ends with complete dilation of uterine orifice by 10 cm (uterine cervix). Contractions are contractions of myometrium that lead to structural changes of the cervix – its shortening and effacement. The beginning of birth is considered to be frequency of contractions at intervals of not less than one in 10 minutes.

I period

Separation of water into the front and rear

Timely discharge of delivery waters (term rupture of membranes) occurs in rupture of thelower pole of amniotic sac. Discharge of anterior waters should take place with completeopening of the uterine mouth or in opening of the uterine mouth which is close tocomplete. When the lower pole of amniotic sac ruptures, 100-200 ml are discharged (inan amniotic sac in total there is 1 liter of amniotic fluid). Early discharge of amniotic fluidin the first stage of labour is discharge in mouth opening up to 7 cm. Discharge ofdelivery waters prior to regular labour is called preterm rupture of membranes, PROM).

Partogram (Friedman curve)

• In the 1st stage of labour there are two phases, as shown in partogram (Friedman curve)

Second period of delivery • The expulsion of fetus from the uterus occurs through the

birth canals, which include bone canal (small pelvis) and soft tissues of the birth canal.

• In the second stage of labour contractions are supplemented by bearing-downs – reflexively arising contractions of striated muscles of the abdominal tension, the diaphragm, abdominal muscles, muscles of perineum.

Biomechanism of delivery

1. The first moment is head flexion. The head bends to the suboccipitobregmaticdiameter. The leading point is the occipital fontanel. The longitudinal suture sets in the transverse dimension of area of brim.

2. The second moment is internal rotation of the head (back of the head anteriorly). The longitudinal suture passes from the transverse dimension of area of brim into suboccipitobregmatic diameter and anteroposterior diameter. Suboccipital fossa (fixation point) is set under pubic symphysis (point of support).

3. The third moment is head extension. The birth of the head through the vulvarring is going by suboccipitobregmatic diameter (9.5 cm) with circumference of 32 cm. The back of the head, the crown, the forehead, the face, the chin are successively born.

4. The fourth moment is internal rotation of shoulders and external rotation of fetal head (restitution, external rotation). When turning, the shoulders are set in anteroposterior diameter of small pelvis outlet plane. The second supporting point is the lower symphysis margin, the second fixation point is on the anterior shoulder of the fetus, in place of deltoid muscle attachment.

Obstetric care in the second stage of delivery

1. Not to oppose the progressive movement of the head

2. Carry out protection of the perineum by suppressing soft tissues

3. Extract the fetus only at the time of contractions and bearing-down

4. Help a little in extension of the head 5. In case of difficulty to remove shoulders to

extract the fetus by axillary cavities – extract first the posterior shoulder and then – the anterior one.

III period of delivery (placental)

• It lasts 10-15 minutes, it should not last more than 30 minutes. At expulsion of afterbirth (by Schultze) detachment begins in the center of the placenta, a retroplacental hematoma forms. At this there is no external bleeding. The hematoma is born with the afterbirth.

• In marginal expulsion of the placenta (by Duncan) there is no retroplacental hematoma, from the very beginning of placental separation, blood discharges appear.

Signs of placental separation1. Chukalov-Kustner sign – when pressing with a palm edge on the uterus above

the pubic symphysis the umbilical cord does not retract into the birth canal.

2. Alfeld sign – separated placenta descends to the lower segment of the uterus or vagina, and therefore the fastener put on the umbilical cord descends.

3. Schroder’s sign – changing the shape and fundal uterine height. Immediately after the birth of the fetus, the uterus takes a rounded shape and is situated on the middle line, the fundus of the uterus is at the level of the omphalus. After separation of the placenta from the uterus – the womb elongates, shifts to the right, uterine fundus rises to the right hypochondrium.

4. Dovzhenko’s sign – retraction of the umbilical cord in a deep inhalation proves that the placenta did not separate. Lack of retraction of the umbilical cord during deep inspiration testifies to separation of the placenta.

5. Strassmann's symptom – vibrational movements of blood in the placenta when tapping the uterus are passed by the umbilical cord only in non-separated placenta.

6. Clein’s sign – during a straining effort the umbilical cord comes out and does not retract back

Placenta

Methods of extracting the afterbirth. The afterbirth includes the placenta, the umbilical

cord, the amniotic membrane. 1. Bayer – Abuladze’s method – with both hands take the abdominal wall into a

longitudinal fold and ask the mother to bear down. The separated afterbirth is born by increasing intra-abdominal pressure.

2. Genter’s method – the bottom of the uterus is put in the midline. The doctor stands at the side of the woman in childbirth face to her feet. Hands with their back surfaces of the main phalanges (hands are as if compressed into fists) are put on the fundus of the uterus to the area of its corners, the doctor gradually presses on the bottom of the uterus in the direction downwards and inside. The woman in childbirth should not bear down.

3. Crede-Lazarevich method. The doctor puts the uterus in its median position through the front abdominal wall. The doctor covers the bottom of the uterus with his palm: the thumb is on the front wall of the uterus (through the front abdominal wall), the palm is at the bottom of the uterus, the four fingers are on the back wall of the uterus. Squeezing of afterbirth is produces – the uterus is compressed in anteroposterior direction and simultaneously its fundus is pressed down and forward along the axis of the pelvis.

Bayer – Abuladze’s method

Genter’s method

Crede-Lazarevich method

Prevention of postpartum hemorrhage

• Intramuscular (IM) injection of 10 units of oxytocin in 2 minutes after the birth the fetus. Intravenous (iv) slow introduction of oxytocin is possible. Upper limit on the amount of physiological blood loss is 0.5% of the woman’s body weight (5 ml per 1 kg of body weight). The tone of the uterus should be assessed every 15 minutes during the first 2 hours of early postpartum period. After childbirth inspection of the birth canals – perineum, vagina, and cervix – is carried out to puerperal injuries (tears). Tears are sutured in aseptic conditions. Within 2 hours the woman in childbirth stays in the delivery room under supervision. Her overall condition, uterine tone are assessed every 15 min as well as the nature of discharges from the genital tract, her blood pressure and pulse are measured, too.