Summary
· A miscarriage is defined as loss of
the products of conception before viability
· About 15% of pregnancies are lost in
the first three months.
· More than half the miscarriages in the
first 13 weeks of pregnancy are caused by chromosomal problems in the foetus
· Miscarriages after the third month are
generally due to illness or other problems with the mother
What
is a miscarriage
A
miscarriage, also known as a spontaneous abortion, is defined as loss of the
products of conception before viability. The products of conception are the
foetus, placenta and amniotic fluid. Viability refers to the baby being able to
survive after delivery. This point is at approximately 26 weeks of gestation.
Normally pregnancy lasts for 40 weeks.
There
are different types of miscarriage:
Threatened
miscarriage
This
refers to bleeding in early pregnancy associated with little or no pain. At
this stage the mouth of the womb or cervix is still closed. It is important to
note that most of these women will not abort.
Inevitable
miscarriage
In
this case the threatened miscarriage has progressed. The woman now experiences
cramping pain in the back and lower abdomen. Clots are often passed as the
mouth of the womb is open and the contents will be lost. Attempts to save the
pregnancy at this stage are usually futile.
Recurrent
miscarriage
This
distressing problem affects a very small number of couples. Medical
investigations are usually started after a third consecutive loss, but some
doctors will investigate earlier. This is because the chances of another failed
pregnancy increase significantly after two losses.
Missed
miscarriage
When
the foetus has died inside the womb but not been expelled, a missed miscarriage
has occurred. In this case the womb will fail to enlarge and the signs of life
such as the foetal heartbeat will disappear.
Septic
miscarriage
Should
the contents of the uterus become infected before, during or after an abortion,
a septic miscarriage has occurred. This is common during unsafe abortions.
What
causes miscarriage
· More than half of all miscarriages
during the first 13 weeks of pregnancy are caused by problems in the foetus’
chromosomes. Chromosomes are tiny structures inside body cells that carry the
genetic material. Each chromosome contains genes that determine a person’s
appearance, sex, and blood type. Problems in the number or structure of the
chromosomes or the genes can lead to miscarriage. Frequently this is nature’s
way of ending a pregnancy in which the foetus was not developing normally.
· Most chromosomal problems occur by
chance and are not likely to recur in later pregnancies. In a small number of
cases, however, chromosomal problems can cause recurrent miscarriages. In such
cases, a karyotype to examine the chromosomal structure should be performed on
the parents.
· Certain abnormalities of the womb
(uterus), which are linked to miscarriage, can be treated surgically. A special
X-ray (hysterosalpingogram) or direct visualisation through a lens
(hysteroscope) can detect abnormalities of the uterine cavity, and an
endometrial biopsy may provide information about the uterine lining, where
implantation occurs.
· In some cases, illnesses of the mother
will lead to miscarriage. Systemic lupus erythematosus, congenital heart
disease, severe kidney disease, high blood pressure, uncontrolled diabetes,
thyroid disease or an intrauterine infection can all interfere with the
pregnancy. When these illnesses are treated, the chances for a successful
pregnancy improve. Such illnesses thus require close monitoring during
pregnancy.
· Disorders of the immune system can
also lead to miscarriage. The immune system defends the body against damage by
recognising and attacking foreign substances. The mother’s immune system will
not normally attack her foetus. Sometimes, however, this protection may be
lost. Problems in the immune system can be diagnosed by blood tests.
· Hormone imbalance may also lead to repeated
miscarriage. The hormone progesterone prepares the lining of the uterus for the
fertilised egg during the second half of the menstrual cycle. When an egg is
fertilised, this hormone continues to prepare the uterine lining for the
embryo. Enough progesterone must be produced to maintain the pregnancy,
otherwise miscarriage will occur. If tests indicate that a woman’s body is not
producing enough progesterone, supplements can be prescribed to correct the
problem.
· In some cases environmental and
lifestyle factors lead to greater risk of miscarriage. Exposure to high levels of radiation or toxic
substances may also be factors in recurrent miscarriages.
Who
suffers miscarriage and who is at risk
Spontaneous
miscarriage is common with about 15% of pregnancies being lost in the first
three months.
Miscarriages
during the first three months tend to be due to problems with the foetus.
Miscarriages occurring in the second three-month period of pregnancy tend to be
related to problems with the mother.
What
are the symptoms and signs of miscarriage
The
main symptoms are pain in the lower abdomen and bleeding from the vagina. In an
inevitable abortion, the cramping pain and bleeding may be severe.
During
the physical examination the doctor will determine whether the mouth of the
womb (cervix) is open. If it is, then the patient is probably experiencing an
inevitable abortion. If the mouth of the womb is still closed, then a
threatened miscarriage is the likely diagnosis.
How
is a miscarriage diagnosed
The
clinical history of pain and bleeding, and a physical examination are usually
sufficient to make the diagnosis.
An
ultrasound may be used to examine the contents of the womb, checking for an
empty sac or signs of life in a foetus. It can also be used to see if all the
products of conception have been passed.
Can
a miscarriage be prevented
Unfortunately,
once a miscarriage has become inevitable, attempts to save it are usually
futile. Research has shown, however, that taking vitamins before and during
pregnancy may lower the risk of miscarriage.
How
is a miscarriage treated
This
depends on the type of miscarriage. Although bed rest is usually prescribed for
a threatened miscarriage, this has not been proven to be effective. The patient
is encouraged not to work and to stay off her feet at home. Women are often
told to avoid intercourse for a while. Although there is not much evidence that
this is harmful, many people suffer guilt feelings if a miscarriage occurs
after intercourse.
In
any case where non-viable products of conception remain in the womb, they must
be removed to prevent further bleeding and infection. This used to be known as
D&C (dilation and curettage) but currently, the common practice is to empty
the womb by manual vacuum aspiration when necessary. If the womb is already
empty, careful monitoring may be all that is required.
Septic
abortion must be treated with intravenous antibiotics and early emptying of the
womb. This condition can be life-threatening.
Since
many women suffer psychological problems as a result of miscarriage,
counselling and support are important aspects of treatment and must not be
overlooked.
What
does not cause miscarriage
It
must be emphasized that exercise, working, and sexual intercourse do not
increase the risk of pregnancy loss in routine (uncomplicated) pregnancies.
However, in the unusual circumstance where a woman is felt by her physician to
be at higher risk of spontaneous abortion, she may be advised to stop working
and refrain from having sexual intercourse. Women with past history of
premature delivery and other specific obstetrical conditions might fall under
this category.
Are
there lifestyle factors associated with miscarriage
Smoking
more than 10 cigarettes per day is associated with an increased risk of pregnancy
loss, and some studies have even shown that the risk of miscarriage increases
with paternal smoking. Other factors, such as alcohol use, fever, use of no
steroidal anti-inflammatory drugs around the time of embryo implantation, and
caffeine use have all been suggested to increase the risk of miscarriage,
although more studies are needed to fully clarify any potential risks
associated with these factors.
Of
course, alcohol is a known teratogen (a chemical that can damage the developing
foetus), so pregnant women are advised to abstain from drinking alcoholic
beverages.
What
happens during miscarriage
The
symptoms you experience will depend on the cause of the miscarriage and how
advanced the pregnancy is/was so may take hours, days or even weeks to complete.
Usually the foetus, placenta and blood from the uterus leave the body through
the vagina. You may discover during a routine scan that there is no heartbeat,
or even an empty foetal sac.
Usually,
by the time bleeding begins your baby has already died, unless it is around the
6 weeks period when only a small amount of blood is lost and then there is an
80% your baby will be fine.
99%
of foetal deaths occur in the first 12 to 14 weeks of pregnancy (1st
trimester), although the actual miscarriage may not happen for some weeks after
the baby dies. Medically this is called a ‘missed abortion’. (The baby is an
“embryo” to the 8th week and a “foetus” after that.)
What
treatment can a woman expect when she has had a miscarriage?
The
central goal of the doctor in this situation will be to try to figure out
whether the woman has passed all of the tissue from the foetus and placenta. If
she has passed all the tissue, she may only require observation by medical
personnel. On the other hand, a woman who has not passed all of the tissue
(incomplete abortion) will usually need suction dilation and curettage
(D&C) of the uterus to remove any retained products of the pregnancy.
Can
something be done to prevent future miscarriages?
The
treatment of recurrent miscarriage depends on what is believed to be the
underlying cause. This often is not as simple as it sounds. Careful evaluation
may turn up several potential factors which alone or together may be
responsible for the pregnancy losses.
If
a chromosomal problem is found in one or both persons, then counselling as to
future risks is the only option for the couple, since there is currently no
method to correct genetic problems.
If
a structural problem is encountered with the uterus, surgical correction could
be contemplated. It should be emphasized that just because a structural
abnormality is found, it does not necessarily mean that it caused the
miscarriage.
Removal
of a fibroid or uterine septum does not guarantee a future successful
pregnancy, since the fibroid or uterine septum may not have been the cause of
miscarriage in the first place.
For
further information visit The Governments Hospital and Clinics throughout the
country, Mother and Child Department Ministry of Health, number of NGO and
Private Clinics, E Mail azadehhassanmd10@gmail.com , and text only on
002207774469/3774469.
