Download miscarriages

Objectives:
At the end of this lecture, the student
should:
 Know the main categories of bleeding in
early pregnancy.
 Can clinically assess a woman with
bleeding in early pregnancy.
 Differentiate between the causes of
bleeding in early pregnancy depending
on the history, clinical signs and certain
investigation when required.

Differentiate between the different types
of abortion depending on clinical
assessment.
 Know the available options of
management for each individual case.

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The three main causes of bleeding in
early pregnancies are:
•
Miscarriage
•
Ectopic pregnancy
•
Gestational trophoblastic disease
miscarriage
Definition:

is the spontaneous termination of
the pregnancy before the fetus is
sufficiently developed to survive
(less than 24 weeks gestation
based on the date of LNMP or fetal
weight less than 500g).
Terminology:
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

In medical contexts, the word "abortion" refers to the
termination of pregnancy, either spontaneously or
intentionally, before the fetus develops sufficiently to
survive.
Many women who have had miscarriages, however,
object to the term "abortion" in connection with their
experience, as it is generally associated with induced
abortions.
In other word, the term abortion most commonly refers to
the induced abortion of a human pregnancy, while
spontaneous abortions are usually termed miscarriages.
Incidence
50% of all conceptions fail (most unrecognized)
 25% of recognized pregnancies are lost, 90 %
of these before 12-14 weeks
 10-20% of pregnant women have 1 sporadic
spontaneous abortion
 2% have 2 consecutive spontaneous abortion
 0.4-1% have 3 consecutive spontaneous
abortion

Causes:
Miscarriages can occur for many reasons, not
all of which can be identified. Some of these
causes include:
 Chromosomal abnormalities
 Endocrine disorders
 Abnormalities of the uterus
 Infections
 Chemical agents
 Psychological disorders
 Immunological disorders

First trimester
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Most clinically apparent miscarriages occur during the first
trimester.
Chromosomal abnormalities are found in more than half of
embryos miscarried in the first 13 weeks.
A pregnancy with a genetic problem has a 95% probability of
ending in miscarriage.
Most chromosomal problems happen by chance, have nothing to
do with the parents, and are unlikely to recur.
Chromosomal problems due to a parent's genes is, however, a
possibility. This is more likely to have been the cause in the case
of repeated miscarriages, or if one of the parents has a child or
other relatives with birth defects. Genetic problems are more likely
to occur with older parents; this may account for the higher
miscarriage rates observed in older women.
Autosomal trisomies are the most common, with
an incidence of 30-35%, followed by triploidies
and monosomies X (45,X)
 Autosomal trisomy is the most frequently
identified chromosomal anomaly associated with
first-trimester abortions.. Trisomies for all
autosomes except chromosome number 1 have
been identified in abortuses, but autosomes 13,
16, 18, 21, and 22 have been found most
commonly.
 Structural chromosomal rearrangement such as
translocations or inversions are present in only
1.5% of abortuses in the general population but
are a significan t cause of recurrent miscarriages.


Another cause of early miscarriage may be
progesterone deficiency. Termed luteal phase
defect, insufficient progesterone secretion by
the corpus luteum or placenta has been
suggested as a cause of abortion. Currently, the
diagnostic criteria and efficacy of therapy for this
supposed disorder require validation. If the
corpus luteum is removed surgically, such as for
an ovarian tumor, progesterone replacement is
indicated in pregnancies less than 8 to 10
weeks
Second trimester
Up to 15% of pregnancy losses in the
second trimester may be due to:
 uterine malformation,
 growths in the uterus (fibroids),
 or cervical problems.
(These conditions may also contribute to
premature birth).
 Problems with the placenta may also
account for a significant number of laterterm miscarriages

General risk factors
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Multiple pregnancies: Pregnancies involving
more than one fetus are at increased risk of
miscarriage.
Uncontrolled diabetes greatly increases the
risk of miscarriage. Women with controlled
diabetes are not at higher risk of miscarriage.
Polycystic ovary syndrome is a risk factor for
miscarriage, with 30-50% of pregnancies in
women with PCOS being miscarried in the first
trimester.
High blood pressure during pregnancy.
Severe cases of hypothyroidism increase the risk of
miscarriage. The effect of milder cases of hypothyroidism
on miscarriage rates has not been established.
 The presence of certain immune conditions such as
autoimmune diseases is associated with a greatly
increased risk of miscarriage.
 Certain illnesses (such as rubella, chlamydia and syphilis
) increase the risk of miscarriage.
 Tobacco (cigarette) smokers have an increased risk of
miscarriage. An increase in miscarriage is also associated
with the father being a cigarette smoker.The husband
study observed a 4% increased risk for husbands who
smoke less than 20 cigarettes/day, and an 81% increased
risk for husbands who smoke 20 or more cigarettes/day.


Cocaine use increases miscarriage rates.
 Physical trauma, and exposure to environmental toxins,
have also been linked to increased risk of miscarriage.
 Advanced maternal age
 The age of the mother is a major risk factor. Miscarriage
rates grow at an ever-increasing rate after age 20.

Pathology
1.Haemorrhage
occurs in the
decidua basalis
leading to local
necrosis and
inflammation.
2. The ovum, partly
or wholly detached,
acts as a foreign
body and initates
uterine contractions.
The cervix begins to
dilate.
3. Expulsion complete,
The decidua is shed
during the next few
days in the lochial flow.
Types:
Threatened miscarriage.
 Inevitable miscarriage.
 Incomplete miscarriage.
 Complete miscarriage.
 Missed miscarriage.
 Recurrent miscarriage.

Blighted ovum: when the gestational sac is
more than 25mm in diameter and no
embryonic or fetal part can be seen, the
term blighted ovum and anembryonic
pregnancy are often used suggesting
wrongly that the sac may have developed
without embryo. The explanation for this
feature is the early death and resorption of
the embryo with persistence of the placental
tissue rather than a pregnancy originally
without embryo.
Threatened miscarriage
Is the earliest stage of most spontaneous miscarriage.
The clinical features of a threatened miscarriage are:
 uterus is normal size for dates
 vaginal bleeding - the bleeding may be slight as faint
brown discharge or a profuse red discharge with clotting
 no products have been passed - do not confuse clots with
products
 cervix is closed
 there is generally no pain although there may be a dull
ache or discomfort due to congestion of the pelvic organs
 pregnancy test is positive
 fetal heart sounds and movements are observed
Threatened
miscarriage
Low abdominal pain acompany
vaginal bleeding
Cervix is closed
unrupture of membrane
Embryo is viable
Pregnancy symptoms are
present

Management:
There are no effective therapies for threatened
abortion.
 Bed rest, although often prescribed, does not
alter the course of threatened abortion.
Acetaminophen-based analgesia may be given
to help relieve the pain.

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there is no evidence that progestogens or human
chorionic gonadotrophins are of any help in the
treatment of threatened abortion
Rhesus prophylaxis if appropriate
Prognosis:
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Occurring commonly, vaginal spotting or heavier
bleeding during early gestation may persist for days or
weeks and may affect one out of four or five pregnant
women.
Overall, approximately half of these pregnancies will
abort, although the risk is substantially lower if fetal
cardiac activity can be documented.
Even without abortion, these fetuses are at increased
risk for preterm delivery, low birthweight, and perinatal
death.
Importantly, the risk of a malformed infant does not
appear to be increased.
Inevitable miscarriage:
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occurs in about 25% of women with a threatened
abortion.
It is characterised by:
considerable bleeding
lower abdominal pain
a dilated cervix
products may have been passed - do not confuse
with clots
Inevitable
miscarriage
Bleeding increased
Pain development
Rupture of membrane
Cevix dilation
Embryo tissue incarcerated in
the cervix
Incomplete miscarriage:
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where the products of conception have not been
completely lost from the uterus.
most likely to occur between 8 to 14 weeks
gestation when the placenta is not expelled
completely and an ERPC is necessary.
In the acute presentation the cervix is dilated,
there is continuing haemorrhage and uterine
contractions. Blood loss may be severe and
require immediate transfusion
In the non-acute presentation a few days after an
abortion, continued blood loss and a bulky, tender
uterus may suggest that an abortion was
incomplete and may necessitate an ERPC
Incomplete
miscarriage
In spite of uterine
contractions and cervical
dilatation, only the fetus
and some membranes are
expelled. The placenta
remains partly attached
and bleeding continues.
This abortion must be
completed by surgical
methods.
Complete miscarriage
The fetus and placenta are expelled completely,
the uterus contracts and bleeding stops. No
further treatment is needed.
Missed Abortion
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In this case, the uterus retains dead products of
conception behind a closed cervical os for days or even
weeks.
After fetal death, there may or may not be vaginal
bleeding or other symptoms of threatened abortion.
For days or weeks, the uterus remains stationary in size,
but then gradually becomes smaller.
Mammary changes usually regress.
If the missed abortion terminates spontaneously, and
most do, the process of expulsion is the same as in any
abortion.

After death of the conceptus, management can be
individualized, depending on individual circumstances.
Expectant, medical, and surgical approaches can all be
reasonable options, each with its own merits and
disadvantages.
Varieties of
spontaneous
abortion