Update: October 2018
Considered to be one of the most formidable obstetric pathologies.
placenta previa, which is observed in 0.2 – 0.6% of cases from
all pregnancies ended in childbirth. Why is this dangerous?
AT первую очередь, предлежание плаценты опасно кровотечением,
the intensity and duration of which can not predict any
doctor. That is why pregnant women with such obstetric pathology
belong to a high-risk group and are carefully observed
What does it mean – placenta previa?
The placenta is a temporary organ and appears only during
gestation With the help of the placenta, the maternal and
fetus, the baby receives nutrients through its blood vessels
substances and gas exchange is carried out. If a беременность протекает
normally, the placenta is located in the area of the uterus or in the area
its walls, as a rule, on the back wall, moving to the side (in
these places blood supply to the muscle layer is more intense).
Placenta is said to be talked about when the latter is located in
uterus wrong, near the lower segment. Basically, previa
placenta – when it overlaps the internal pharynx, in part or
completely and is located below the presenting part of the baby, thus
blocking his path for birth.
ATиды предлежания хореона
There are several classifications described obstetric
pathology. The following is generally accepted:
- полное предлежание плаценты – случай, когда внутренний зев перекрывается дольками
the placenta, that is, it “moves” from one uterine wall to
other, and the fetal membranes during vaginal examination are not
determined (another name is the central presentation);
- incomplete placenta previa or partial presentation – in
In this case, the placenta does not completely close the inner throat and
divided into 2 subspecies:
- lateral previa – when 1 or 2 lobes of the placenta are presented and
palpable fetal membranes (determined by the roughness);
- marginal presentation – in this case, the extreme area of the placenta
is located in the inner throat area, but does not go beyond its
We should also highlight the low placentation or low
placenta previa during pregnancy.
Low placentation is localization of the placenta at level 5 and
less than centimeters from the internal pharynx in the third trimester and on
level 7 or less centimeters from the internal pharynx in term
pregnancy to 26 weeks.
Низкое расposition плаценты является самым благоприятным
option, bleeding during gestation and childbirth
rarely occur, and the placenta itself is prone to so-called migration,
that is, increasing the distance between it and the inner throat. it
due to stretching of the lower segment at the end of the second and in
the third trimester and the growth of the placenta in the direction that
better blood supply, that is, to the uterus.
In addition, allocate predlazhaschie vessels. At the same time vessel / vessels
located in shells that are in the area of the inner
pharynx. This complication poses a threat to the fetus in the event of
violation of the integrity of the vessel.
Causes that placenta previa can be
associated with the state of the maternal organism, and
features of the ovum. The main cause of complications
are dystrophic processes in the uterine mucosa. Then
fertilized egg is not able to penetrate
forces her down below. Предрасполагающи
- chronic inflammation of the uterus;
- numerous genera;
- abortion and curettage of the uterus;
- роды и аборты, осложнившиеся гнойно-септическ
- uterine tumors;
- scars on the uterus (operative delivery, removal
- congenital malformations of the uterus;
- internal endometriosis;
- sexual infantilism;
- drug use;
- first birth at 30 years or more;
- impaired hormonal ovarian function;
- multiple pregnancy.
Chronic endometritis, multiple intrauterine devices
manipulations (scraping and abortions), myomatous nodes lead to
the formation of the defective second phase of the endometrium, in which he
preparing for implantation of a fertilized egg. Therefore, when
the formation of the chorion, she is looking for the most favorable place that
well-supplied and optimal for placentation.
The severity of proteolytic properties also plays a role.
germ. That is, if the enzyme formation mechanism,
dissolving the decidual layer of the endometrium, slowed down, then the egg cell
It does not have time to implant in the “right” section of the uterus (in the bottom or on
back wall) and descends below, where it is embedded in the mucous membrane.
Symptoms of placenta previa
During pregnancy, complicated placenta previa, conditionally
divided into “silent” and “pronounced” phases. �”Mute” phase flows
practically asymptomatic. ATо время измерения живота высота дна
матки больше нормы, что обусловлено высоким расpositionм
presenting part of the child. Himself the fetus is often located in the uterus
wrong, there is a high percentage of pelvic, oblique, transverse
provisions, due to the localization of the placenta in the lower part
матки (она «вынуждает» ребенка занять правильное position и
Symptoms of placenta previa due to its incorrect
localization. Pathognomic sign of this obstetric
осложнения является наружное bleeding. Bleeding from the uterus
may occur at any stage of pregnancy, but more often in recent
недели gestation it имеет две причины.
- ATо-первых, в сроке 34 – 38 недель появляются ложные схватки
(brexton-gix cuts), which contributes to the stretching of the lower
Division of the uterus (preparation for childbirth). Placenta that does not have
ability to reduce, “comes off” from the uterine wall, and from its
разорванных сосудов начинается bleeding.
- ATо-вторых, «развертывание» нижнего сегмента матки во второй
half of pregnancy is intense, and the placenta does not have time
grow to the appropriate size and it starts
�”Migrate”, which also causes placental abruption and
Characteristically, bleeding always begins suddenly, often
against the background of absolute rest, for example, in a dream. When will arise
bleeding and how intense it will be, impossible
Of course, the percentage of profuse bleeding in the central
previa significantly more than with incomplete previa, but also
it’s not obligatory. The greater the gestational period, the greater the chances
the occurrence of bleeding.
- For example, a regional placenta previa of 20 weeks may
no way to manifest itself, and the bleeding will occur (but not
Required) only in childbirth.
- Low placentation often proceeds without clinical
symptoms, pregnancy and childbirth proceed without features.
One of the typical characteristics of bleeding with a breech is
their repeatability. That is, every pregnant woman should know about this and
always be on your guard.
- The amount of bleeding varies: from intense to
- The color of blood secreted is always scarlet, and the bleeding
To provoke the occurrence of bleeding is capable of any
- straining during bowel movements or during urination
- intercourse or vaginal examination
Another difference in placenta previa is progressive
anemization of women (see low hemoglobin during pregnancy). Volume
blood loss almost always does not correspond to the degree of anemia,
which is much higher. ATо время повторяющихся кровянистых
discharge of blood does not have time to regenerate, its volume remains
low, which leads to low blood pressure, development
ДATС-синдрома или гиповолемическог
ATследствие неправильного расположения плаценты, прогрессирующей
anemia and reduced blood volume develops
placental insufficiency which leads to intrauterine
delayed fetal development and the occurrence of intrauterine
Пример из практики: AT женской консультации
a woman of about 35 years was observed – second pregnancy, desired. On
the first ultrasound in the period of 12 weeks, she revealed a central
placenta previa. An explanatory report was held with the pregnant woman.
conversation, given relevant recommendations, but we are with a colleague
fear and anticipation of bleeding were observed. Bleeding behind
during the whole period of pregnancy, she appeared only once, in the period of 28 –
29 weeks, and that, not bleeding, but insignificant discharge
bloody. Almost the entire pregnancy the woman was on
больничном листе, в палату патологии ее госпитализировал
threatened terms and in the period of bloody discharge. Woman
safely reached almost deadline and in 36 weeks was sent
to the maternity ward where she successfully prepared for the upcoming
planned caesarean section. But, as is often the case, on holiday
день у нее началось bleeding. Therefore, it was immediately convened
operating team. The baby was born wonderful, even without
signs of hypotrophy (in children). The sequel was separated without problems, the uterus
well shrunk. Послеоперационны
й период тоже протекал
smooth. Of course, everyone breathed a sigh of relief that such a huge
the burden fell from his shoulders. Но this случай скорее нетипичен для
central presentation, and the woman can be said lucky that
everything went a little blood.
How to diagnose?
Placenta previa is a hidden and dangerous pathology. If a
pregnant bleeding has not yet been, then suspect the presentation of
it is possible, but it is only possible to confirm the diagnosis using
additional survey methods.
Onтолкнуть на мысль о предлежащей плаценте помогает тщательно
collected history (in the past there were complicated childbirth and / or
postpartum, multiple abortions, diseases of the uterus and
appendages, uterus surgery, etc.), the current
pregnancy (often complicated by the threat of termination) and data
external obstetric study.
At external examination the height of the bottom of the uterus is measured, which is greater
estimated duration of pregnancy, as well as improper position
fetal or pelvic presentation. Palpation of the presenting part does not give
clear sensations, as is hidden under the placenta.
In the case of a pregnant woman who complains about
bleeding, she is hospitalized in the hospital for exclusion or
confirmation of the diagnosis of a similar pathology, where, if there is
opportunity, conduct ultrasound, preferably vaginal sensor. Inspection
in mirrors is carried out to establish the source of the bloody
discharge (from the cervix or varicose veins of the vagina).
The main condition that must be observed during the inspection
mirrors: the study is conducted against the background of the operating room
and necessarily heated mirrors so that in case of amplification
bleeding is not slow to begin surgery.
Ultrasound remains the safest and most accurate method
this pathology. In 98% of cases the diagnosis is confirmed,
ые результаты наблюдаются при чрезмерно
filled bladder, therefore, in the study of the ultrasonic sensor
bladder should be moderately full.
Ultrasound can not only establish
previa choreon, but to determine its type, as well
area of the placenta. Duration of the ultrasound during the entire period
gestation of the fetus is somewhat different from the time at normal
pregnancies and correspond to 16, 24 – 26 and 34 – 36 weeks.
How to lead and give birth to pregnant women
With confirmed placenta previa, treatment depends on
many circumstances. The term is taken into account first.
pregnancy, when bleeding occurred, its intensity, volume
blood loss, the general condition of the pregnant and the readiness of the generic
If the chorion’s presentation was established in the first 16 weeks,
spotting absent and does not suffer general condition
women, it is carried out on an outpatient basis, having previously explained the risks and
giving the necessary recommendations (sexual rest, restriction of physical
loads, prohibition of bathing, visiting baths and saunas).
Upon reaching 24 weeks, the pregnant woman is hospitalized in the hospital,
where preventive therapy is carried out. Also hospitalized
subject to all women with bleeding regardless of his
intensity and duration of pregnancy. The treatment described obstetric
- medical and protective regime;
- treatment of placental insufficiency;
- anemia therapy;
- tocolysis (prevention of uterine contractions).
- the appointment of sedatives (tincture of peony, motherwort
- maximum limitation of physical activity (bed rest
- Therapy of placental insufficiency prevents delay
fetal development and lies in the appointment:
- antiaggregants to improve the rheological qualities of blood
- vitamins (folic acid, vitamins C and E)
- actovegin, cocarboxylase
- Essentiale-Forte and other metabolic drugs
- It is mandatory to take iron supplements for
повышения гемоглобина (сорбифер-дуруле
с, тардиферон и
- antiaggregants to improve the rheological qualities of blood
Tocolytic therapy is carried out not only in the case of existing
threatened abortion or threatening premature
childbirth, but also for the purpose of prevention, are shown:
- antispasmodics (no-shpa, magnne-B6, sulphate magnesia)
- tocolytics (ginipral, partusisten), which are introduced
- in case of threatened or beginning preterm labor
necessarily carried out prevention of respiratory disorders
и (дексаметазон, гидрокортизон)
ью 2 – 3 дня.
If bleeding occurs, the intensity of which threatens
woman’s life, regardless of the period of gestation and the condition of the fetus
(мертвый или нежизнеспособный
What to do and how to reproduce with the presentation of the chorion? this
Doctors put the question on reaching the period of 37 – 38 weeks. If a
there is a lateral or marginal presentation and there is no bleeding,
then in this case the waiting tactic (the beginning of independent
childbirth). With the disclosure of the cervix at 3 centimeters produced
amniotomy for prophylactic purposes.
If bleeding occurs before regular contractions and
the presence of a soft and tensile cervix is also produced
amniotomy. At the same time, the baby’s head goes down and presses to
the entrance to the pelvis, and, accordingly, presses the exfoliated lobules
the placenta, which causes arrest of bleeding. If a амниотомия не
The effect of a woman is delivered by an abdominal route.
A caesarean section is routinely performed for pregnant women who have
full previa diagnosed, or incomplete
предлежания и сопутствующей патологии (неправильное position
fetus, presenting pelvic end, age, scar on the uterus, other).
Moreover, the technique of operation depends on which wall
the placenta is located. If a плацента локализуются по передней
wall, held corporal caesarean section.
This obstetric pathology is often complicated by the threat
interruption, intrauterine hypoxia, delayed fetal development.
In addition, often placenta previa is accompanied by its true
increment. AT the third stage of childbirth and the early postpartum period
high risk of bleeding.
Пример из практики: AT акушерское отделение
A perennial woman was reported complaining of bleeding in
within three hours of the birth canal. Diagnosis at admission:
Pregnancy 32 weeks. Regional presentation of the placenta.
Fetal developmental delay of fetus 2 degrees (by ultrasound). Uterine
bleeding. Contractions in a woman were absent, fetal heartbeat
deaf, irregular. My colleague and I immediately called San. aviation,
since it is not clear yet what the matter may end in addition to the obligatory
cesarean section. A live premature baby was removed during the operation.
child. Attempts to remove the afterbirth were unsuccessful (true
increment of the placenta). The scope of operation was extended to extirpation.
uterus (the uterus is removed along with the cervix). Woman translated into
Intensive care ward where it stayed for a day. Baby died
on the first day (prematurity plus intrauterine delay
fetal development). The woman was left without a uterus and a child. Here is such
sad story, but, thank God, even though mother was saved.