Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Midwifery Anatomy + Physiology > Uterine Contractions and Hormones > Flashcards

Uterine Contractions and Hormones Flashcards

1
Q

What is the first stage of labour?

A
  • Progressive cervical dilation timed from the onset of regular coordinated contractions
  • Accompanied by progressive effacement and dictation of the cervix.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What marks the end of the first stage of labour?

A
  • Full dilatation of the cervix (4-10cm)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Which two hormones change in ratio at 37 weeks gestation?

A
  • Progesterone (levels DROP)
  • Oestrogen (levels INCREASE)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

At 37 weeks, what are uterine muscles more sensitive to?

A
  • OXYTOCIN
  • PROSTAGLANDINS

> (They stimulate an INCREASE in intracellular free calcium which stimulates uterine contractions)

> This stimulates the action of filaments (ACTIN AND MYOCIN) into the myometrial cells to contract.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the 3 main principles of uterine contractions?

A
  • FUNDAL DOMINANCE
  • POLARITY
  • CONTRACTION AND RETRACTION
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is fundal dominance?

A
  • From the point of the FUNDUS that the contraction spreads from the FUNDUS down the body of the UTERUS to the CERVIX.
  • Contraction lasts the LONGEST and STRONGEST at the FUNDUS because the UPPER SEGMENT contracts strongly and the LOWER SEGMENT dilates.

(this is FETAL AXIS PRESSURE) - the force transmitted by the uterine contractions down the fetal spine to the head.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What happens to the contraction at the fundus? (fundal dominance) WHY?

A
  • It lasts the longest and strongest
  • The upper segment contracts strongly
  • The lower segment dilates
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is fetal axis pressure? (fundal dominance)

A
  • The force transmitted by the uterine contractions down the fetal head to the fetal spine.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is polarity?

A
  • NEUROMUSCULAR HARMONY between the upper and lower segments.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is contraction and retraction?

A
  • After each contraction, the MUSCLE CELLS never fully relax, so with each successive contraction the MUSCLES become SHORTER.
  • This means that the UPPER SEGMENT of the uterus becomes SMALLER and THICKER so the foetus is pushed DOWN the PELVIS.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are muscle contractions triggered by?

A
  • A rise in INTRACELLULAR CONCENTRATION of CALCIUM IONS.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What do calcium ions bind to and what does this cause?

A
  • They bind to a calcium binding protein called CALMODULIN (CAM).
  • Causes the formation of a CA-CAM complex which activates MYSION LIGHT CHAIN KINASE (MLCK)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

When is MLCK inhibited?

A
  • When progesterone levels DROP.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What does MLCK cause myosin to do?

A
  • Causes myosin to be phosphorylated and will interact with actin causing contractions.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

The influx of intracellular calcium ions increase due to which two hormones?

A
  • OXYTOCIN
  • PROSTAGLANDINS
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What two hormones decrease intracellular calcium by promoting the uptake in stores?

A
  • PROGESTERONE
  • PROSTACYCLINS
17
Q

What is the Ferguson reflex?

A
  • A feedback loop that helps establish progress in labour.
18
Q

What are the 4 main points of the Ferguson Reflex?

A
  1. Baby pushes against the cervix causing it to stretch.
  2. Stretching of cervix causes nerve impulses to be sent to the brain.
  3. Brain stimulates posterior pituitary gland to release oxytocin.
  4. Oxytocin causes smooth muscle lining of uterus to contract.
19
Q

What does stretching of the cervix cause? (FR)

A
  • Nerve impulses to be sent to the brain.
20
Q

What does the posterior pituitary gland release? What does this do? (FR)

A

> Oxytocin
- Causes smooth muscle lining of the uterus to contract.

21
Q

What is released from the posterior pituitary gland?

22
Q

Apart from the posterior pituitary gland, where is oxytocin also produced?

A
  • Fetal pituritary gland
  • Placenta
  • Fetal membranes
23
Q

What is the role of oxytocin in relation to uterine contractions?

A
  • Increases influx of intracellular calcium ions.
24
Q

What is the midwifes role in stimulating the release of oxytocin?

A
  • Dimming lights/ relaxing music (Reduces adrenaline)
  • Giving oxytocin as an IV infusion for IOL
25
Q

Where are prostaglandins released from and what is their role?

A
  • Released from fetal membranes
  • Promote softening
    of cervix/ cervical ripening
26
Q

What do prostaglandins increase the production of?

A
  • Influx of intracellular calcium ions
27
Q

What is the midwives role in prostaglandins?

A
  • Prostaglandins can be administered for IOL with a prostin pessary
28
Q

Where does a secretion of higher levels of relaxin take place?

A
  • The placenta
29
Q

What hormone does the placenta secrete higher levels of?

30
Q

What is the role of relaxin? (x2)

A
  • Relaxin loosens up some of the pelvic ligaments.
  • Loosens the pubic symphysis joint to increase the pelvic outlet.

Midwifery Anatomy + Physiology (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions