Normal Labour

Normal Labour

Case: A 24 year old G2P1, a booked case of your hospital comes to you in labour. She tells you that she has been having labour pain for almost 5 hours now. On abdominal palpation, you can feel 3 strong uterine contractions every 10 mins. The head is engaged. On PS, cervix is 4cm dilated with effacement. On PV, the head is felt at “0” station. How will you manage the case now?

What is labour?

Expulsion of fetus through uterus after the age of viability

What is normal labour ?

Vertex presentation
Spontaneous onset of labour at term
Natural termination through vagina
Without any assistance
Without any complications

Onset of labour

Fetus – Anterior pituitary and adrenal gland
Placenta – Hormones
Mother – Uterus, Hormone and Prostaglandins

At term- Increased release of ACTH from the Ant Pituitary

↓

Increased secretion of cortisol

↓

Increased in oestrogen

↓

Increased oxytocin receptors in the myometrium

Increased prostaglandin synthesis

Prostaglandins

Decidua
Membranes
Placenta
Liquor

Diagnosis of onset of labour

Painful intermittent uterine contractions
Show
Dilatation of cervix
Formation of bag of water

Characteristics of uterine contractions

Intermittent
Regular interval
Relaxation in between
Followed by retraction

Starts from cornua – descends down

Fundal dominance

Synchronous

Intra amniotic pressure rise to > 20mm Hg

1st stage – 40-50 mm Hg

2nd stage – 100-120 mm Hg

Characteristics of cervical dilatation

Progressive 1cm per hour in primi
1.5 cm per hour in multi
Effacement – progressive shortening of cervix due to gradual merging up of upper part of cervix to the lower segment
May occur before dilatation of cervix in primi
Occurs together with dilatation during labour