Pregnancy is a very exciting time in every woman’s life. It is a period that gradually transforms a woman to a mother. The pregnancy period is marked by both happiness and anxiety especially when a woman is carrying her first baby.
While most concerns are normal due to the flurry of changes taking place in the mother-to-be, there are some very real and dangerous complications that warrant immediate medical attention and care. One such complication that can occur during pregnancy is placenta previa.
What is placenta previa?
Placenta previa is also known as low-lying placenta and occurs when the placenta attaches to the lower part of the uterus either partially or fully blocking the cervix.
The placenta is a sac like structure that covers the fetus and starts to form immediately after conception. Its main function is to provide nutrients and oxygen to the baby while simultaneously removing and discarding the baby’s waste products. The placenta normally attaches to a spot higher up in the uterine wall and the umbilical cord arises from it. This umbilical cord serves as the connection between the mother and the baby, till the baby is in the womb.
The problem with the placenta attaching to the lower portion of the uterine wall is that it can detach during labor when the cervix widens causing massive bleeding. Placenta previa occurs in about one in 200 pregnancies.
Types of placenta previa
Placenta previa can be divided into three types:
In this case, the placenta completely covers the cervix. Caesarean section is the only way to deliver the baby in such cases.
In this case, the placenta partially occludes the opening of the cervix. Here too Cesarean section is the best option for delivery.
In this case, the edge of the placenta just touches the cervix but does not block it. In such cases it is possible to deliver the baby normally though a Cesarean section may be called for depending on the nature of the case.
Causes and risk factors
Placenta previa is mainly found in older mothers, usually 35 years or older. The condition is more common in women who smoke; those who already have at least one baby; those who have closely spaced children; those who are carrying twins or triplets, etc.; those who have had many children (multiparity), etc.
The main cause for placenta previa is some kind of abnormality in the uterine wall. This may be the result of previous interventions including cesarean section, D&C (dilation and curettage) procedure, or any other surgery, or there may not be any reason at all. A woman is also more likely to have placenta previa if she had this condition in her previous pregnancy.
Symptoms Of Placenta accreta
The most common symptom is painless bleeding during the second and third trimester of pregnancy. The bleeding tends to stop after a while but recurrence is very common. Some woman also experience contractions.
What are the possible complications?
Placenta previa may predispose the mother to life-threatening hemorrhage at the time of delivery. There is also the risk of hemorrhage after delivery (post partum). Such hemorrhage can lead to infections, blood clots and sometimes even death.
Premature labor and pre-term delivery is also most often a possible outcome of placenta previa.
Placenta accreta is a possible but uncommon complication in which the placenta is attached very firmly to the placental wall, so much so that it does not detach on its own. This results in severe bleeding and a hysterectomy may be the only option in most such cases.
Diagnosis of Placenta accreta
Any bleeding especially in the second and third trimester of pregnancy warrants a thorough medical checkup. Placenta previa can be easily diagnosed by ultrasound imaging.
It is not uncommon to find a low lying placenta in the early weeks of pregnancy, and this does not call for unwanted worries and fear as it is natural for the placenta to move upwards as the pregnancy progresses and the uterus grows. This process is called placental migration. Therefore very few women who have low lying placenta early in their pregnancy actually have true placenta previa at full term.
Different types of ultrasound scans can be used to detect placenta previa. A routine abdominal ultrasound scan can detect up to 95% of placenta previa cases. There are however chances of both false positive and false negative results while using a normal ultra sound scan. A vaginal examination is usually not done as it may trigger bleeding.
Transvaginal ultrasonography is found to be more accurate in diagnosing placenta previa as compared to transabdominal ultrasonography. It is also considered safer. This is done by inserting a transducer inside the vagina.
Transperineal ultrasonography maybe used in combination with transabdominal Ultrasonography to rule out false positive results. Though rare, an MRI (magnetic resonance imaging) scan may be done to detect placenta previa. It also helps to detect placenta accreta.
How is placenta previa managed?
The immediate management of placenta previa is bed rest. Depending on the condition of the patient, she may be advised to stay in the hospital or take rest at home. If the bleeding is not too severe, bed rest at home usually suffices. The patient will normally be advised to stay away from exercises, sex, strenuous activity, vaginal examinations, etc.
If the bleeding is heavy, the patient may need to be hospitalized. Blood transfusions may be needed if there is considerable loss of blood. All efforts will be made to prolong the pregnancy till the fetus is at least 36 weeks old. If this is not possible, the mother may be injected with corticosteroids to help the baby’s lungs to develop so that it can breathe outside the uterus.
In case bleeding is severe, the delivery is performed immediately irrespective of the term.
There are two related conditions that might also lead to vaginal bleeding. These are:
Placental abruption or Abruptio placentae
This occurs when a normally implanted placenta detaches from the uterine wall before the baby is born. This will result in excess bleeding and also the baby is deprived of nutrients and vital oxygen. This condition is dangerous for both the baby and the mother.
This is a condition where the blood vessels from the placenta or umbilical cord are left unprotected by the amniotic sac. When these blood vessels cross the cervix, it is called vasa previa. Rupturing of these blood vessels can be extremely dangerous for the baby.
How to cope?
Being diagnosed with placenta previa can be very scary. Yet, the important thing to know is that with the right kind of care, it is possible to deliver a healthy baby. It is important to understand all the aspects of this condition thoroughly and be prepared mentally for any immediate intervention.
A mother-to-be must be aware that she should keep herself happy and tension free during pregnancy as this has an important bearing on her baby’s health. A good rapport with the gynecologist is a must as a good and informative interaction with the doctor can serve to allay most fears.
Most cases of placenta previa are delivered by a cesarean section, so it is better if a woman can prepare herself earlier for this eventuality. If bed rest has been advised, the mother-to be can spend her time reading up relevant information and connecting with other parents or parents-to-be in similar conditions. There are also many support groups for people in this condition.
The good news is that placenta previa is almost always diagnosed before delivery and this makes the prognosis good as necessary precautions for the delivery can be taken beforehand. It is only necessary for the mother-to-be to keep herself mentally strong to deliver a perfectly healthy baby.
Photo Credit- Thinkbaby.co.uk