Physiology of the
puerperium and postnatal
care
Ann Kingscott
Pre session work
Revisit the physiology of pregnancy and with the following consider the
reversal to the pre pregnant state -
Read: Harrison J (2000) Physiological changes of the puerperium
British Journal of Midwifery 8 (8) 483-488.
What do the NMC (2004) Midwives rules and standards state about the
role of the midwife during the postnatal period?
Read: Ockleford, Berryman & Hsu (2004) Postnatal care: what new
mothers say British Journal of Midwifery Vol 12 No. 3 p166-170
Read Okon (2004) Health Promotion: Partners perception of
Breastfeeding British Journal of Midwifery Vol 12 No. 6 p387-399
Access www.childcarseats.org.uk Consider this in relation for infant
safety.
Read NICE (2006) Routine postnatal care of women and their babies.
www.nice.org.uk
Definition
Puerperium – a period from the expulsion
of the placenta until 6 – 8 weeks after
birth, during which time the uterus and
other organs and systems return to their
pre pregnant state and lactation is
initiated.
Many changes take place within the first
10 -14 days.
Role changes
Postnatal period page 7
‘….. means the time
after the end of labour
during which the
attendance of a
midwife upon the
woman and baby is
required, being not
less than 10 days and
for such longer period
as the midwife
considers necessary’.
Endocrine changes
Removal of the placenta alters the
physiological state – rapid clearance of
hormones from plasma and extra cellular
fluid
HPL disappears by 1-2 days
hCG detected for 2 weeks
Alpha feta protein – several weeks
Oestrogens/progesterone – rapid loss
Ovarian function – low for first 2 weeks
FSH/LH suppressed during pregnancy
remain low for 2 weeks following birth,
both in lactating and non lactating women,
gradual increase over 6 weeks.
Tends to be a period of infertility
Placental Site
Dramatic decrease in size brings uterine walls into
close apposition and transforms uterus into hard
globular mass.
This has the effect of applying pressure on the
placental site - prevents haemorrhage
18cm diameter- 9cm
Promoted by continual action of oxytocin.
Uterine Involution
Weight of uterus after birth 1 kg
2/52 no longer palpable
6/52 50-60g
? Caused by withdrawal of placental
hormones
By day 5 - wt 500gms
Involution – ‘turning inwards’
3 processes
Ischemia occurs as a result of collapse of
blood vessels
Autolysis is physiological process by which
involution of uterus is achieved. Breakdown
of intracellular protein by proteolytic &
hydrolytic enzymes.
Phagocytocis – disposes of elastic/fibrous
tissue
Myometrial cells – shorter & thinner.
No correlation between route of delivery or
choice of feeding and speed of involution
Much variability in rate of involution
Endometrium
Regeneration begin 1-2 days after birth
Differentiation into 2 layers
superficial – barrier to infection
basal – source of new
endometrium
Regeneration takes approx 2-3 weeks.
Placental site regenerates slowly over 6 -7
weeks
Lochia
Reflects the process of involution and restoration
of the endometrium – characteristic postnatal
discharge
Mean duration – 21-33 days
Shorter in multips and with smaller babies
Lochia rubra: fresh blood from placenta
Lochia serosa: brownish pink after 4 days
Lochia alba: white
Cervix and Vagina
Cervix bruised, swollen, oedematous and little
tone.
By end of 1st week cervix decreased in size,
closed by end 2nd week
Vagina smooth, oedamatous, pouting and blue-
ish.
After 3-4 wks ruggae appear.
Episitomy
Lacerations
Sexual intercourse –
lubrication
Cardiovascular Changes
Following birth dramatic changes in haemodilution
– cardiovascular instability.
Cardiac output elevated for 1-2 hours after birth
begins to stabilise after about 10 mins. Decreases
until 10th day. Normal by 2 weeks.
Cardiovascular system reverts to normal in 2 - 4
weeks.
Days 2 -5 diuresis dissipates the extra cellular
fluid, up to 3 Kgs weight loss
Coagulation
Profound physiological changes in the blood and
dramatic changes in coagulation and haemostatic
mechanisms.
Changes protect women from haemorrhage.
Levels remain high for 10 days
DVT/PE – increased risk if trauma, sepsis,
immobility
Blood Volume Changes
Decreases rapidly over 24 hours. Increase
in haemconcentration, Hb rises.
By 6-9 weeks returned to normal.
Urinary Tract
24-48 hours rapid diuresis – decreases
plasma volume of blood to non-pregnant
levels.
High oestrogen augments effects of ADH -
increases blood volume
Larger quantities of nitrogen – autolysis
Trauma to bladder base, oedema
Progesterone causes
dilation of urinary tract
in pregnancy.
Care and
management –
decreased tone,
oedema – prolonged
labour, type of birth
Pressure of fetal head
– transient loss of
bladder sensation
Sphincter tone may
be altered – stress
incontinence
Other body systems
Respiratory system
Digestive system
Musculo-Skeletal system
Midwives rules and standards
NMC (2004)
Childbirth – includes antenatal, intranatal
and postnatal periods page 6
‘Childbirth is more than the act of giving
birth. For the woman it is a continuous
process from conception through pregnancy,
labour, birth and beyond. It is essential that
anyone providing midwifery care during this
time has the appropriate knowledge, skills
and competence to do so’
Activities of a midwife
NMC (2004) page 36
To provide sound family planning information and
advice
To care for and monitor the progress of the mother
in the postnatal period and to give all necessary
advice to the mother on infant care to enable her to
ensure the optimum progress of the newborn infant
To examine and care for the newborn infant; to take
all initiatives which are necessary in case of need
and to carry out immediate resuscitation
Issues to consider
Patterns of care
Multi agency working
Clinical care – mother
baby as a
unit/separation/loss
Holistic care
Individualised care
Examination of the
newborn – extended
role
Identifying
problems/risk
Emotional well being
Mental health –
leading cause of
maternal death
Sexuality, sexual
health, contraception.
Social exclusion
Disability/impairment
Evaluation
Infant feeding
Skin to skin
Early initiation of
breast feeding
Conflicting advice
Support for
chosen method
Audit
NICE (2006)
recommendations
Transition to parenthood
Parent education
Partner
Debrief – impact of birth/ outcome
Revision points
Know the physiology!
‘Cinderella of the
maternity services’
Communication –
listening to women
Informed choice
Continuity of care
NICE (2006) Routine
postnatal care of women
and their babies -
recommendations.