Physiology & Dx Of Labour

Question 1

Definition of labour

Answer 1

Is is the process by which the fetus is delivered after the 24th week of gastation

Question 2

Labour is characterized by:

Answer 2

• onset of uterine countactions
• cervical effacement and dilatation
• rupture of memebranes with leakage of amniotic fluid
• descent of the presenting part through the birth canal
• birth of baby
• delivery of the placenta and membranes.

Question 3

Each uterine contraction must be followed by a resting phase, why?

Answer 3

To maintain placental blood flow and adequate perfusion of the fetus

Question 4

When does labor start?

Answer 4

When the factors that inhibit contractions and maintain a closed cervix diminish and are over taken by the actions of factors that do the opposite

Question 5

Myometrial contraction occurs in response to:

Answer 5

Oxytocin & and prostaglandin, which increase intracellular Ca+

Question 6

Which segment of the uterus becomes thicker contracted and which becomes thinner and more stretched?

Answer 6

The upper segment becomes thicker and actively contracted

Question 7

Ferguson reflex:

Answer 7

It is 6 feedback
The pressure of presenting part of fetus against the cervis trigger oxytocin release from posterior pituitary
Leading to strong contraction and further increase the pressure against cervix&raquo_space; ++oxytocine

Question 8

Types of pelvis:

Answer 8

Gynaecoid pelvis (50%): (female pelvis) most suitable for child birth
Anthropoid pelvis (25%):
Oval, see in tall woman
Android pelvis (20%):
(male pelvis) Childbirth is difficult
Wider transverse diameter
Platypelloid (flat) pelvis (5%):
Kidney shaped
Rare
Wider transverse diameter
not conductive to vaginal delivery

Question 9

Diameter of fetal skull:

Answer 9

Suboccipito-frontal: 10cm
Occipito-frontal: 11cm
submento-bregmatic: 9.5cm
suboccipito-bregmatic: 9.5cm
occipito-mental: 13cm

Question 10

Fetal head enters the pelvis in a …., rotates in the ….. and delivers in ……

Answer 10

Transverse position
Midpelvis
AP position

Question 11

Pelvic dimensions may increase during labor due:

Answer 11

Pelvic ligament laxity

Question 12

Fetal Position that is most favorable for vaginal birth:

Answer 12

Fetus in a Flexed occipito-anterior with gynaecoid pelvis

Question 13

Active phase of 1st stage is considered abnormal if:

Answer 13

If it occurs at less than 1cm in 2hrs

Question 14

Active phase of 1st stage is variable in length (2-6hrs)

Answer 14

It is shorter in multiparous woman

Question 15

There is no maternal urge to push, and fetal head is still relatively high in the pelvis

Answer 15

The passive phase of 2nd stage

Question 16

There is a maternal urge to push because the fetal head is low, often visible

Answer 16

The active phase of 2nd stage

Question 17

Which stage is its length affected by using the epidural anaesthetia

Answer 17

Second stage

Question 18

The placenta is usually delivered within:

Answer 18

A few minutes (30min)

Question 19

A third stage lasting more than … is defined as abnormal:

Answer 19

30 minutes
Unless the woman has opted for physiological management (60 minutes)

Question 20

Both prolonged and precipitous labor increase maternal and fetal morbidity and mortality
T or F?

Answer 20

T

Question 21

When the labor is regarded as prolonged:

Answer 21

When it lasts longer than 12 hours in nulliparous women and 8 hours in multiparous women.

Question 22

Step of mechanism of labor

Answer 22

Engagement
Descent
Flexion of the head
Followed by internal rotation
Extension
Restitution
External rotation
Ended by delivery of shoulders and fetal body

Question 23

Engagement in nulliparous women

Answer 23

It occurred in nulliparous women prior to labor, usually by 37wks

not for multiparous

Question 24

How to diagnose engagement

Answer 24

By palpation of the number of fifths of fetal head abdominally
if more than two-fifths, the head is not yet engaged

Question 25

The descent occurs in:

Answer 25

1st stage and passive phase of the 2nd stage of labor
as a result of uterine contractions.