Session 10- Labour and Delivery

Question 1

what is considered pre term labour

Answer 1

before 37th week

Question 2

what is the biological term for miscarriagw

Answer 2

parturition

Question 3

what is considered the first stages of labour

Answer 3

creation of birth canal

release of structures which normally retain the fetus in utero

the enlargement and realignment of the cervix and vagina

Question 4

what is considered the second stage of labour

Answer 4

expulsion of fetus

Question 5

what is considere dyhe third stage of labour

Answer 5

expulsion of the placenta and changes t minimise blood loss from the mother

Question 6

when does the foetus first become palpable

Answer 6

12 weeks

Question 7

where does the fetus reahc by 20 weeks

Answer 7

umbilicus

Question 8

where doesthe foetus reach by 36 weeks

Answer 8

xiphisternum

Question 9

what is the commonest lie of the foetus

Answer 9

longitudinal which the head or buttox posterior

Question 10

what is the presentation of the fetus

Answer 10

the part of the fetus which is adjacent to the pelvic inlet

-if the baby lies longitudinally this will be the head- cephalic or the breech- podalic

Question 11

what is the most common presentaion and position

Answer 11

longitudinally with cephalic presentaion

Question 12

how long does the birth canal have to e

Answer 12

10cm

Question 13

what allows cervical dilatation

Answer 13

structural changes known as cervical ripening

forceful contractions of the uterine smooth musce

Question 14

what os effacement

Answer 14

thinning of th cervix

Question 15

how does cervical softening occur

Answer 15

marked reduction of collagen and marked increase of GAGs

this decreases the aggregation of collagen fibres whic causes them to loosen

influx of inflammatory cells and nitric oxide output

Question 16

what triggers cervical softening

Answer 16

prostaglandins namely e2 and f2 alpha

Question 17

what is the onset of labour

Answer 17

a relatively sudden increase in the frequency and force of contractions

Question 18

what two hornones are involed in the onset of labouyr

Answer 18

prostaglandins- enhance the release fo calcium from intracellular stores

oxytocin- lowers threshold for triggereing action potentials

Question 19

what is the fergusons reflex

Answer 19

increased oxytocin secretion

sensory receptors in the vagina and cervix are stimulated by contractions

excitation passes via afferent nerves to the hypothalamus promoting massive oxytocin release

Question 20

what is brachystasis

Answer 20

at each contraction the muscle fubres shorten but do not relax fully which causes the uterus to shorten progessively

this pushes the presenting part into the birth canal and stretches the cervix over it

Question 21

when does the first stage of labour end

Answer 21

when the cervix is dilated by 10cm

Question 22

how long does the second stave last

Answer 22

1 hour- multiparous

up to 2 hours in primagravida

Question 23

what happens during the second stage of labour

Answer 23

1. the descended head flexes as it meets the pelvic floor, reducing the diameter of presentation
2. there is then internal rotation
3. the sharply flexed head descends to the vulva, so stretching the vagina and perineum
4. the head os then delivered - crowning- and as it emerges it rotates back to its orginal position and extends
5. the shoulders then rotate followed by the head and the shoulders deliver followed rapidly by the rest of teh fetus

Question 24

what reduced blleding durng the third stage of labor

Answer 24

the contraction of the uterus compresses blood vessels

normally enhanced by an oxytocic drug