32 weeks belongs to the late stage of pregnancy, at this time the placenta position occupies about 1/4 of the whole uterine cavity, so it is difficult for the placenta praevia to grow up to become a normal position after 32 weeks.
Under normal circumstances, the placenta should be attached to the bottom of the uterus, the anterior wall, the posterior wall, or the left or right side wall. If the lowest point of the placenta reaches or covers part or all of the endocervical opening after 28 weeks of gestation, it is called placenta praevia. It is difficult for the placenta previa to grow up to become a normally positioned placenta after 32 weeks of gestation.
According to the position of the edge of the placenta in relation to the endocervical opening, it can be classified as low lying placenta, marginal placenta previa, partial placenta previa, and central placenta previa. Placenta praevia and placenta marginata can be delivered vaginally, while placenta centrale is an indication for cesarean section and requires cesarean section to end the labor.
The cause of placenta praevia is unknown, but the main risk factors are history of multiple miscarriages, puerperal infections, advanced age, history of cesarean section, and ultrasound indication of placenta praevia before 28 weeks of gestation.
Once the diagnosis of placenta praevia is made, anal examination should be prohibited. Placenta praevia and placental abruption are common causes of antepartum hemorrhage. If the placenta previa is still present after 32 weeks of gestation, it is necessary to pay attention to the observation of painless and unprovoked vaginal bleeding. Once the symptom is detected, it is necessary to go to the hospital in time and do the relevant treatments, and do not solve the problem at home by oneself, so as not to cause the adverse consequences of pregnancy.