about placenta previa was known in ancient times: about the disease mentioned in the works of Hippocrates.Even then, doctors have known that the location of the placenta in the uterus exit is very dangerous to a woman's life since birth in such a case, always accompanied by heavy bleeding.
structure and function of the placenta
placenta (afterbirth) - a body that exists only in women during pregnancy, providing a link with the mother of the child.After delivery, the placenta moves through the birth canal.
placenta is a disc with a diameter of about 20 cm and a thickness of 3 cm and attached to the uterine wall on one side.On the other hand it is attached to the placenta with umbilical cord vessels.
Located placenta usually in the posterior wall of the uterus.The placenta begins to function fully after I trimester (first three months), reaching full maturity a month before the birth.It carries metabolism improves metabolism and losing weight without dieting between mother and fetus:
What is placenta previa and its species
placenta previa - the placenta is not attached to the wall of the uterus, in which partit is in the internal uterine os (the junction of the body of the uterus into the cervix).The incidence of placenta previa is an average of half a percentage point.At repeated pregnancies, this pathology is more common.
are two main types of placenta previa: total or central (inner cervix is fully closed by the placenta) and incomplete or partial, in which the placenta partially covers the opening of its edge or occupies a significant portion.Incomplete presentation is divided in turn into a side (the opening is not fully closed) and regional (in the uterine mouth is only the edge of the placenta).During labor, the location of the placenta may vary.For example, a complete placenta previa, according to the onset of labor, sometimes gradually transformed into a lateral and lateral to the regional and vice versa.
most common cause of placenta previa is changing the state of the mucous membrane of the uterus after the abortion, obstructed labor and puerperal infection.Changes in the lining of the uterus prevent the introduction of a fertilized egg in the place of attachment of the ovum, where the placenta is formed.Relatively often in the placenta previa develop additional slices.An important role in the development of placenta previa playing inflammation and proliferation of connective tissue in the decidua (changes in the mucous membrane of the uterus, which is produced during pregnancy and torn away from the placenta after birth).
placenta previa appears mainly uterine bleeding Uterine bleeding is menstruation - a sign of a serious breach , which usually begin for no apparent reason or due to physical stress, nervous stress.Most often, such bleeding begins in the third trimester of pregnancy (starting from 24 weeks).The lower the place of attachment of the placenta, the sooner there is bleeding.The majority of women with incomplete placenta previa bleeding begins at birth, with a full - during pregnancy.
Bleeding may periodically break off with decreasing intensity of uterine contractions.At the same time stop bleeding during delivery by partial placenta previa promotes rupture of membranes and intense uterine contractions: the placenta during battle descends, and the presenting part of the fetus presses the separated part of the placenta to the place of detachment, pinches the blood vessels.In cases of complete placenta previa bleeding is usually progressive and can result in hemorrhagic shock - a life-threatening condition.
most dangerous complications associated with repeated bleeding that can aggravate already developed a state of shock.The source of such bleeding may be the cervix ruptures, which has a lot of blood vessels due to the proximity of the placenta.In postpartum hemorrhage often occur due to the lack of contractile ability of the uterus to the point of attachment of the placenta.
Placenta previa can be complicated getting into the blood vessels of amniotic fluid, which reduces the rolling properties of the blood (amniotic fluid embolism), and contributes to increased bleeding.The proximity of the placenta to the vagina increases the risk of getting an infection in the blood vessels, which is dangerous for both the mother and the fetus.Detachment of the placenta from the uterine wall will cause oxygen deficiency (hypoxia) in the fetus, which has a negative impact on his condition in the first place, the state of the brain.
Diagnosis and treatment
Identify placenta previa during the ultrasound examination, which is conducted during pregnancy several times.A woman is required to warn that even when a small amount of bleeding is necessary to call an ambulance and go to the hospital.Minor bleeding treated using bed rest, suppression of uterine contractions, as well as the introduction of the drug increases the rolling capacity of the blood and strengthens the walls of blood vessels.With strong bleedings performed caesarean section.
Proper monitoring of pregnant women at the antenatal clinic provides early detection and treatment of placenta previa.