Q: Dr. please, what is the cause of placenta previa ? Can it be cured or prevented ?
A: Placenta previa (PP) is a condition associated with the placenta…you already figured that out, right? 😀 The placenta is created during pregnancy and is attached to the wall of the uterus (the womb) by blood vessels. It is through the placenta that the baby receives vital nutrients and oxygen and also through this that it excretes waste products. The baby is connected to the placenta through the umbilical cord. So this is a pretty important organ in the general scheme of things. The baby’s and mother’s blood do not mix in the placenta usually, though. The baby’s blood flows on one side and the mother’s on the other side.
The placenta usually implants at the top part of the uterus or the side, but in placenta previa the placenta attaches low in the uterine wall and covers the mouth of the womb (the cervix) partially or completely. It could be just low lying, near the cervix but not covering it, just covering part of the cervix or fully covering it. Due to this abnormal placenta position, pregnant women with PP would show up in hospital with bright red vaginal bleeding which may happen with or without contractions.
What causes this? Well, in instances where the placenta is bigger than normal or in cases where surgery had been performed on the uterus. Thus, women with multiple pregnancies (twins, triplets etc), who have had fibroid surgery or previous Caesarian Section, who have had children before may be at risk of this. Other risk factors include age at pregnancy older than 35 years, smoking, use of cocaine etc.
The doctor (obstetrician) will order a scan to confirm the diagnosis. Low lying placenta that hardly get to the opening of the cervix can actually be ‘drawn’ up as the uterus expands to accommodate the growing baby in it. However, the women with complete PP are most likely to go through Caesarian Section.
Can you prevent it? No, you really can’t 😦 What to do? Once you notice any vaginal bleeding, please be sure to see your doctor. PP is likely to cause bleeding from sometime around the second trimester of pregnancy, but of course, every episode of bleeding in pregnancy, irrespective of trimester, should be checked out in the hospital. Depending on the severity of the bleeding and the age of the pregnancy, the doctor would decide whether bed rest or emergency Caesarian section would be applicable. If bed rest is recommended, sexual intercourse and physical exertion including exercise, at this time may not be wise. Please discuss this with your doctor.
You’ve got to make sure that the person with PP is under the care of a good obstetrician. This is not the time to play hooky and try out different treatment options from unorthodox practitioners (not that any time is a good time, anyway :D). It may very well be that if the bleeding continues significantly, the baby may be delivered pre-term. So you have to be in a center that is equipped to handle that eventuality. Better safe than sorry 🙂
Have a fabulous evening 🙂