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Although the risk of placental abruption cannot be eliminated, it can be reduced. Avoiding tobacco, alcohol and cocaine during pregnancy decreases the risk. Staying away from activities which have a high risk of physical trauma is also important. Women who have high blood pressure or who have had a previous placental abruption and want to conceive must be closely supervised by a doctor.
The risk of placental abruption can be reduced by maintaining a good diet including taking folic acid, regular sleep patterns and correction of pregnancy-induced hypertension.
It is crucial for women to be made aware of the signs of placental abruption, such as vaginal bleeding, and that if they experience such symptoms they must get into contact with their health care provider/the hospital "without any delay".
There is no effective pharmacological treatment for retained placenta. It is useful ensuring the bladder is empty. However, ergometrine should not be given as it causes tonic uterine contractions which may delay placental expulsion. Controlled cord traction has been recommended as a second alternative after more than 30 minutes have passed after stimulation of uterine contractions, provided the uterus is contracted. Manual extraction may be required if cord traction also fails, or if heavy ongoing bleeding occurs. Very rarely a curettage is necessary to ensure that no remnants of the placenta remain (in rare conditions with very adherent placenta such as a placenta accreta).
However, in birth centers and attended home birth environments, it is common for licensed care providers to wait for the placenta's birth up to 2 hours in some instances.
It is recommended that women with vasa previa should deliver through elective cesarean prior to rupture of the membranes. Given the timing of membrane rupture is difficult to predict, elective cesarean delivery at 35–36 weeks is recommended. This gestational age gives a reasonable balance between the risk of death and that of prematurity. Several authorities have recommended hospital admission about 32 weeks. This is to give the patient proximity to the operating room for emergency delivery should the membranes rupture. Because these patients are at risk for preterm delivery, it is recommended that steroids should be given to promote fetal lung maturation. When bleeding occurs, the patient goes into labor, or if the membranes rupture, immediate treatment with an emergency caesarean delivery is usually indicated.
The prognosis of this complication depends on whether treatment is received by the patient, on the quality of treatment, and on the severity of the abruption. Outcomes for the baby also depend on the gestational age.
In the Western world, maternal deaths due to placental abruption are rare. The fetal prognosis is worse than the maternal prognosis; approximately 12% of fetuses affected by placental abruption die. 77% of fetuses that die from placental abruption die before birth; the remainder die due to complications of preterm birth.
Without any form of medical intervention, as often happens in many parts of the world, placental abruption has a high maternal mortality rate.
An initial assessment to determine the status of the mother and fetus is required. Although mothers used to be treated in the hospital from the first bleeding episode until birth, it is now considered safe to treat placenta previa on an outpatient basis if the fetus is at less than 30 weeks of gestation, and neither the mother nor the fetus are in distress. Immediate delivery of the fetus may be indicated if the fetus is mature or if the fetus or mother are in distress. Blood volume replacement (to maintain blood pressure) and blood plasma replacement (to maintain fibrinogen levels) may be necessary.
Corticosteroids are indicated at 24–34 weeks gestation, given the higher risk of premature birth.
In places where a Caesarean section could not be performed due to the lack of a surgeon or equipment, infant could be delivered vaginally. There were two ways of doing this with a placenta previa:
- The baby's head can be brought down to the placental site (if necessary with Willet's forceps or a vulsellum) and a weight attached to its scalp
- A leg can be brought down and the baby's buttocks used to compress the placental site
Oxytocin is typically used right after the delivery of the baby to prevent PPH. Misoprostol may be used in areas where oxytocin is not available. Early clamping of the umbilical cord does not decrease risks and may cause anemia in the baby, thus is usually not recommended.
Active management of the third stage is a method of shortening the stage between when the baby is born and when the placenta is delivered. This stage is when the mother is at risk of having a PPH. Active management involves giving a drug which helps the uterus contract before delivering the placenta by a gentle but sustained pull on the umbilical cord whilst exerting upward pressure on the lower abdomen to support the uterus.
Another method of active management which is not recommended now is fundal pressure. A review into this method found no research and advises controlled cord traction because fundal pressure can cause the mother unnecessary pain. Allowing the cord to drain appears to shorten the third stage and reduce blood loss but evidence around this subject is not strong enough to draw solid conclusions.
Nipple stimulation and breastfeeding triggers the release of natural oxytocin in the body, therefore it is thought that encouraging the baby to suckle soon after birth may reduce the risk of PPH for the mother. A review looking into this did not find enough good research to say whether or not nipple stimulation did reduce PPH. More research is needed to answer this question.
of fetal membranes (afterbirth) is observed more frequently in cattle than in other animals. In a normal condition, a cow’s placenta is expelled within a 12-hour period after calving.
Intravenous oxytocin is the drug of choice for postpartum hemorrhage. Ergotamine may also be used.
Oxytocin helps the uterus to contract quickly and the contractions to last for longer. It is the first line treatment for PPH when its cause is the uterus not contracting well. A combination of syntocinon and ergometrine is commonly used as part of active management of the third stage of labour. This is called syntometrine. Syntocinon alone lowers the risk of PPH. Based on limited research available it is unclear whether syntocinon or syntometrine is most effective in preventing PPH but adverse effects are worse with syntometrine making syntocinon a more attractive option. Ergometrine also has to be kept cool and in a dark place so that it is safe to use. It does reduce the risk of PPH by improving the tone of the uterus when compared with no treatment however it has to be used with caution due to its effect raising blood pressure and causing worse after pains.
More research would be useful in determining the best doses of ergometrine, and syntocinon.
The difficulty using oxytocin is that it needs to be kept below a certain temperature which requires resources such as fridges which are not always available particularly in low-resourced settings. When oxytocin is not available, misoprostol can be used. Misoprostol does not need to be kept at a certain temperature and research into its effectiveness in reducing blood loss appears promising when compared with a placebo in a setting where it is not appropriate to use oxytocin. Misoprostol can cause unpleasant side effects such as very high body temperatures and shivering. Lower doses of misoprostol appear to be safer and cause less side effects.
Giving oxytocin in a solution of saline into the umbilical vein is a method of administering the drugs directly to the placental bed and uterus. However quality of evidence around this technique is poor and it is not recommended for routine use in the management of the third stage. More research is needed to ascertain whether this is an effective way of administering uterotonic drugs. As a way of treating a retained placenta, this method is not harmful but has not been shown to be effective.
Carbetocin compared with oxytocin produced a reduction in women who needed uterine massage and further uterotonic drugs for women having caesarean sections. There was no difference in rates of PPH in women having caesarean sections or women having vaginal deliveries when given carbetocin. Carbetocin appears to cause less adverse effects. More research is needed to find the cost effectiveness of using carbetocin.
Tranexamic acid, a medication to promote blood clotting, may also be used to reduce bleeding and blood transfusions in low-risk women, however evidence as of 2015 was not strong. A 2017 trial found that it decreased the risk of death from bleeding from 1.9% to 1.5% in women with postpartum bleeding. The benefit was greater when the medication was given within three hours.
In some countries, such as Japan, methylergometrine and other herbal remedies are given following the delivery of the placenta to prevent severe bleeding more than a day after the birth. However, there is not enough evidence to suggest that these methods are effective.
Taking aspirin is associated with a 1% to 5% reduction in pre-eclampsia and a 1% to 5% reduction in premature births in women at high risk. The World Health Organization recommends low-dose aspirin for the prevention of pre-eclampsia in women at high risk and recommends it be started before 20 weeks of pregnancy. The United States Preventive Services Task Force recommends a low-dose regimen for women at high risk beginning in the 12th week. Benefits are less if started after 16 weeks.
Some disorders and conditions can mean that pregnancy is considered high-risk (about 6-8% of pregnancies in the USA) and in extreme cases may be contraindicated. High-risk pregnancies are the main focus of doctors specialising in maternal-fetal medicine.
Serious pre-existing disorders which can reduce a woman's physical ability to survive pregnancy include a range of congenital defects (that is, conditions with which the woman herself was born, for example, those of the heart or , some of which are listed above) and diseases acquired at any time during the woman's life.
Supplementation with a balanced protein and energy diet does not appear to reduce the risk of pre-eclampsia. Further, there is no evidence that changing salt intake has an effect.
Supplementation with antioxidants such as vitamin C, D and E has no effect on pre-eclampsia incidence; therefore, supplementation with vitamins C, E, and D is not recommended for reducing the risk of pre-eclampsia.
Calcium supplementation of at least 1 gram per day is recommended during pregnancy as it prevents preeclampsia where dietary calcium intake is low, especially for those at high risk. Low selenium status is associated with higher incidence of pre-eclampsia.
The first step in management of uterine atony is uterine massage. The next step is pharmacological therapies, the first of which is oxytocin, used because it initiates rhythmic contractions of the uterus, compressing the spiral arteries which should reduce bleeding. The next step in the pharmacological management is the use of methylergometrine, which is an ergot derivative, much like that use in the abortive treatment of migraines. Its side effect of hypertension means its use should not be used in those with hypertension or pre-eclampsia. In those with hypertension, the use of prostaglandin F is indicated (but beware of its use in patients with asthma).
Another option Carbetocin and Carboprost where Oxytocin and ergometrin is inappropriate.
A Dutch 2010 research showed that "low-risk" pregnancy in the Netherlands may actually carry a higher risk of perinatal death than a "high-risk" pregnancy.
In rare cases, inherited bleeding disorders, like hemophilia, von Willebrand disease (vWD), or factor IX or XI deficiency, may cause severe postpartum hemorrhage, with an increased risk of death particularly in the postpartum period. The risk of postpartum hemorrhage in patients with vWD and carriers of hemophilia has been found to be 18.5% and 22% respectively. This pathology occurs due to the normal physiological drop in maternal clotting factors after delivery which greatly increases the risk of secondary postpartum hemorrhage.
Another bleeding risk factor is thrombocytopenia, or decreased platelet levels, which is the most common hematological change associated with pregnancy induced hypertension. If platelet counts drop less than 100,000 per microliter the patient will be at a severe risk for inability to clot during and after delivery.
Warfarin, heparin and LMWH do not seem to pass into breast milk, so these are not contraindicated in breastfeeding.
Treatment may be delivery by caesarean section and abdominal hysterectomy if placenta accreta is diagnosed before birth. Oxytocin and antibiotics are used for post-surgical management. When there is partially separated placenta with focal accreta, best option is removal of placenta. If it is important to save the woman's uterus (for future pregnancies) then resection around the placenta may be successful. Conservative treatment can also be uterus sparing but may not be as successful and has a higher risk of complications.
Techniques include:
- Leaving the placenta in the uterus and curettage of uterus. Methotrexate has been used in this case.
- Intrauterine balloon catheterisation to compress blood vessels
- Embolisation of pelvic vessels
- Internal iliac artery ligation
- Bilateral uterine artery ligation
In cases where there is invasion of placental tissue and blood vessels into the bladder, it is treated in similar manner to abdominal pregnancy and manual placental removal is avoided. However, this may eventually need hysterectomy and/or partial cystectomy.
If the patient decides to proceed with a vaginal delivery, blood products for transfusion and an anesthesiologist are kept ready at delivery.
Antepartum bleeding (APH), also prepartum hemorrhage, is bleeding during pregnancy from the 24th week (sometimes defined as from the 20th week) gestational age to full term (40th week). The primary consideration is the presence of a placenta previa which is a low lying placenta at or very near to the internal cervical os. This condition occurs in roughly 4 out of 1000 pregnancies and usually needs to be resolved by delivering the baby via cesarean section. Also a placental abruption (in which there is premature separation of the placenta) can lead to obstetrical hemorrhage, sometimes concealed. This pathology is of important consideration after maternal trauma such as a motor vehicle accident or fall.
Other considerations to include when assessing antepartum bleeding are: sterile vaginal exams that are performed in order to assess dilation of the patient when the 40th week is approaching. As well as cervical insufficiency defined as a midtrimester (14th-26th week) dilation of the cervix which may need medical intervention to assist in keeping the pregnancy sustainable.
Inducing labor artificially starts the labor process by using medication and other techniques. Labor is usually only induced if there is potential danger on the mother or child.
There are several reasons for labor induction; the mother's water breaks, and contractions have not started, the child is post-mature, the mother has diabetes or high blood pressure, or there is not enough amniotic fluid around the baby. Labor induction is not always the best choice because it has its own risks. Sometimes mothers will request to be induced for reasons that are not medical. This is called an elective induction. Doctors try to avoid inducing labor unless it is completely necessary.
Vasa previa is seen more commonly with velamentous insertion of the umbilical cord, accessory placental lobes (succenturiate or bilobate placenta), multiple gestation, IVF pregnancy. In IVF pregnancies incidences as high as one in 300 have been reported. The reasons for this association are not clear, but disturbed orientation of the blastocyst at implantation, vanishing embryos and the increased frequency of placental morphological variations in in vitro fertilisation pregnancies have all been postulated.
A woman who has reached 42 weeks of pregnancy is likely to be offered induction of labour. Alternatively, she can choose expectant management, that is, she waits for the natural onset of labour. Women opting for expectant management may also choose to carry on with additional monitoring of their baby, with regular CTG, ultrasound, and biophysical profile. Risks of expectant management vary between studies.
Because pregnancy is outside the uterus, abdominal pregnancy serves as a model of human male pregnancy or for females who lack a uterus, although such pregnancy would be dangerous.
Cases of combined simultaneous abdominal and intrauterine pregnancy have been reported.
The reported incidence of placenta accreta has increased from approximately 0.8 per 1000 deliveries in the 1980s to 3 per 1000 deliveries in the past decade.
Incidence has been increasing with increased rates of Caesarean deliveries, with rates of 1 in 4,027 pregnancies in the 1970s, 1 in 2,510 in the 1980s, and 1 in 533 for 1982–2002. In 2002, ACOG estimated that incidence has increased 10-fold over the past 50 years. The risk of placenta accreta in future deliveries after Caesarian section is 0.4-0.8%. For patients with placenta previa, risk increases with number of previous Caesarean sections, with rates of 3%, 11%, 40%, 61%, and 67% for the first, second, third, fourth, and fifth or greater number of Caesarean sections.
Unfractionated heparin, low molecular weight heparin, warfarin (not to be used during pregnancy) and aspirin remain the basis of antithrombotic treatment and prophylaxis both before and during pregnancy.
While the consensus among physicians is the safety of the mother supersedes the safety of the developing fetus, changes in the anticoagulation regimen during pregnancy can be performed to minimize the risks to the developing fetus while maintaining therapeutic levels of anticoagulants in the mother.
The main issue with anticoagulation in pregnancy is that warfarin, the most commonly used anticoagulant in chronic administration, is known to have teratogenic effects on the fetus if administered in early pregnancy. Still, there seems to be no teratogenic effect of warfarin before six weeks of gestation. However, unfractionated heparin and low molecular weight heparin do not cross the placenta.
Principles of management are to treat the shock and replace the uterus. The patient should be moved rapidly to the OR to facilitate anesthesia monitoring during this procedure. Usually this complication is only recognized after delivery of the placenta, wherein pitocin has already been started, which just exacerbates the problem. The uterus clamps down around the inversion making it very difficult to perform a replacement. This is a true obstetrical emergency, so extra doctors, nurses, anesthesiologists should be summoned to the room to assist. The pitocin should be turned off immediately. Giving tocolytics such as terbutaline or magnesium sulfate have a lower success rate. Halothane and Nitroglycerine (100mcg to 200 mcg intravenously) have a higher success rate.
Once you have achieved uterine relaxation, place your fist into the vagina. Find the biggest part of the inversion and push with your fist cephalward to replace the uterus. This takes firm steady force, so keep your fist in the vagina if you need to rest your hand. Then continue more force toward the fundus to replace the uterus. You can use your left hand on the outside of the abdomen to help you feel where the fundus should be replaced. This helps guide the angle of your fist in replacing the uterus. Once it is replaced, give the patient Misoprostol 1000 mcgs rectally to help with increasing uterine tone. Other medications such as Methergine and Hemabate can be used. If you have heavy bleeding, consider inserting a Bakri balloon into the uterine cavity to tamponade the bleeding.
These patients have usually sustained heavy blood loss, and should be monitored in the ICU postoperatively. If you have given nitroglycerine, they must have cardiac monitoring postoperatively.
Other personnel should be monitoring vital signs, ordering blood products, assisting the anesthesiologist, drawing labs, and stabilizing the patient. Remember that nitroglycerine can cause hypotension, which can be reversed with ephedrine.
If external replacement fails, a laparotomy may be required, in which the uterus is gently pulled the right way round using forceps.