Why is there bleeding with placenta previa?

Leaky vessels. Previa: Placenta overlies the cervix/birth canal. Gr 1 means placenta is close, Gr 4 means it's directly overlying/blocking the baby's exit -- high chance of preterm labor & bleeding; you'd need a C/S at 36-37wks. More common in woman w/ hx of C/S & smoking. Not much you can do but wait. If dx'ed early, the uterus still grows/stretches and a placenta can migrate away even in 3rd tri. Follow w/ US.
Maternal vessels. Placenta previa means that the internal cervical os is covered by trophoblast. When labor occurs, or the amniotic membranes rupture, the placenta starts detaching from the lower uterus, so the maternal blood circulating through the placenta exits from its proper place and manifests as vaginal bleeding (not fetal blood).
Placenta. When placenta is on lower uterine segment, it is called placenta previa. When plans is completely covering the internal os it is complete placenta previa. When the lower segment of uterus gets stretched in last trimester, it distrupts the placenta to cause bleeding.

Related Questions

Why is the bleeding painless from placenta previa?

Placenta prevIa. The stretching of lower uterine segment causes the disruption in blood supply to the plaventa. The blood usually comes out of the internal os. So this bleeding is painless. Rarely is there is collection of blood behind placenta than it can be painful. Read more...
No contractions. Because the bleeding does not involve the contractile part of the uterus, only the placenta over the cervix. The placenta is devoid of innervation, therefore the mother does not experience pain in bleeding previa unless preterm labor is also present. Read more...
Leaky placental vsls. Previa: Placenta overlies the cervix/birth canal. Gr 1 means placenta is close, Gr 4 means it's directly overlying/blocking the baby's exit -- high chance of preterm labor & bleeding; you'd need a C/S at 36-37wks. More common in woman w/ hx of C/S & smoking. Not much you can do but wait. If dx'ed early, the uterus still grows/stretches and a placenta can migrate away even in 3rd tri. Follow w/ US. Read more...

How long does bleeding with placenta previa last?

Varies. Placenta previa is a condition in which the placenta implants directly over the cervix and blocks the birth canal. For this reason, women with placenta previa require a c-section. Since the placenta is exposed more, it is more prone to bleeding as well. Bleeding ranges from continuous or occasional spotting to torrential hemorrhage that could threaten the lives of both mother and baby. Read more...
Unknown. Previa: Placenta overlies the cervix/birth canal. Gr 1 means placenta is close, Gr 4 means it's directly overlying/blocking the baby's exit -- high chance of preterm labor & bleeding; you'd need a C/S at 36-37wks. More common in woman w/ hx of C/S & smoking. Not much you can do but wait. If dx'ed early, the uterus still grows/stretches and a placenta can migrate away even in 3rd tri. Follow w/ US. Read more...

Is there a chance of bleeding even after correction of placenta previa?

Yes . There is no surgical or mefical treatment yo correct placenta previa however sometimes the placenta can change or move so that it no longer overlies the opening of the cervix if you have true placenta previa it needs to be closely monitored especially the closer you get to going in labor as at that time your cervix will dilate and can cause severe bleeding. Read more...

Will vaginal spotting/bleeding stop placenta previa resolves? Does recurrent bleeding in 2nd tr indicate that placenta previa is unlikely to resolve?

Yes and no. Bleeding that is directly attributable to placenta previa should subside/cease once the previa resolves. However, bleeding in the setting of placenta previa is something that needs to be monitored VERY closely...like in the hospital under the direct care of an OB/GYN. The recurrent nature of the vaginal bleeding is not necessarily an indication that the previa won't resolve or less likely. Read more...
2 questions here. Answer to number one, not always. Answer number 2, not always. You will need periodic ultrasound monitoring to follow this issue and, most importantly, if you have significant bleeding, pain, or preterm labor get to hospital right away. Don't plan any trips. You need to be very careful or this may threaten the lives of both you and your baby. Follow your OBs advice and make sure you follow up. Read more...
Previa. True placental previa is a condition in which the placenta is attached to the womb and covers the cervical canal completely. A partial placenta previa is attached to the lower uterine segment, and overlaps the cervical canal only marginally. The latter can "resolve" as the pregnancy progresses, and eventually not cover any of the open cervical canal. Previas usually require a cesarean section . Read more...

I was diagnosed w/placenta previa I have on and off light bleeding which also has a foul smell I was told I have no Infections. Is this normal?

Blood can smell.. Bloody vaginal discharge can have a bad smell even if nothing else is going on. Best wishes! Read more...
Consult your Ob. A persistent or intermittent bloody vaginal discharge may create an environment for a shift in the normal bacteria.You should talk to your gyn. If you are having a continuous offensive vaginal odor. Read more...

How dangerous is C-section with placenta previa? I have heard there is a high risk of bleeding out!?

Good Hands Can Help. Placenta previa can pose difficulties during a cesarean because the placenta can be located in the area that the incision in uterus is made to deliver the baby. This may cause increased bleeding. A physician with skill should have little problem with getting it under control. More dangerous is placenta previa in someone who has had a cesarean with a prior pregnancy. But again, experience prevails. Read more...
Increased risk. What you have heard is correct; exsanguination can occur in undiagnosed accreta/previa in small hospitals with inexperienced surgeon(s). Seek expert care if uou have placenta previa (including maternal-fetal medicine ultrasound and consultation), avoid all nsaids/sex/travel/unnecessary car rides/heavy lifting/straining/constipation and deliver in a large, tertiary care hospital [blood bank/icu]. Read more...

I'm 19 weeks of gestation with complete placenta previa, can I take Duvadilan as a tocolytics? Provided that I had painless bleeding one week ago.

Depends. If you are having contractions then it is prudent to take tocolytics. If you are contracting and you have placenta previa, you should be in the hospital. Please see your doctor. Read more...