CHILDBIRTH
CH ILD BIRTH , COM PLICATIONS O F
CHILDBIRTH
Contracting uterus
Dilated
Vagina (birth
Placenta
Bladder
Widened vagina
cervix
canal)
îDÜÜUCÎ
Mother's spine
Baby's
head
CERVIX DILATED
EMERGENCE OF HEAD
C
childbirth
The process by which an
infant leaves the
uterus
and enters the
outside world. Childbirth
(labour)
normal-
ly takes place between 38 and 42 weeks
of pregnancy and occurs in 3 stages.
The onset of the 1st stage of labour is
marked by regular contractions which
become progressively more painful, and
occur at shorter intervals. The
cervix
be-
comes thinned and softened and then
begins to dilate with each contraction.
During this time, there may be a “show'',
the mucous plug that blocks the cervi-
cal canal during pregnancy is expelled
as a bloody discharge. “Breaking of the
waters'', the rupture of the
amniotic sac,
may occur as a slow trickle of fluid or a
sudden gush. The cervix is fully dilated
when the opening has widened to about
10 cm in diameter. This may take 12
hours or more for a first baby, but only a
few hours for subsequent babies.
In the
2
nd stage of labour, the woman
feels the urge to push with each strong
contraction. As the baby's head descends
into the
vagina
, it rotates to face the
mother's back. The
perineum
is stretched
thin at this stage, and an
episiotomy
may be performed to prevent it from
tearing. Once the baby's head is deliv-
ered, the rest of the body follows with
the next contractions. After delivery, the
umbilical cord
is clamped and cut.
In the 3rd stage of labour, the delivery
of the placenta takes place.
The various forms of pain relief avail-
able during normal labour and delivery
include opioid
analgesic drugs
,
epidural
anaesthesia
, and
pudendal block
.
childbirth, complications of
Difficul-
ties and problems occurring after the
onset of
labour
. Some complications are
potentially life-threatening, especially if
they impair the baby's oxygen supply
(see
fetal distress
). Premature labour
may occur, with the delivery of a small,
immature baby (see
prematurity
). Pre-
mature rupture of the
amniotic sac
can
lead to infection in the
uterus
, requiring
prompt delivery of the baby and treat-
ment with
antibiotic drugs
.
Slow progress in the
1
st stage of a
normal labour due to inadequate con-
tractions of the uterus is usually treated
with intravenous infusions of synthetic
oxytocin.
If the mother cannot push
strongly enough, or contractions are in-
effective in the
2
nd stage of labour, the
baby may be delivered by
forceps deliv-
ery
,
vacuum extraction
, or
caesarean
section.
Rarely, a woman has
eclampsia
during labour, requiring treatment with
anticonvulsant drugs
and oxygen, and
induction of labour
or caesarean section.
Bleeding before labour (
antepartum
haem orrhage
) or during labour may be
due to premature separation of the
pla-
centa
from the wall of the uterus or, less
commonly, to a condition called
placenta
praevia,
in which the placenta lies over
the opening of the
cervix
. Blood loss
after the delivery (
postpartum haem or-
rhage
) is usually due to failure of the
uterus to contract after delivery, or to
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