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.

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.

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".

Ideally the management of abdominal pregnancy should be done by a team that has medical personnel from multiple specialties. Potential treatments consist of surgery with termination of the pregnancy (removal of the fetus) via laparoscopy or laparotomy, use of methotrexate, embolization, and combinations of these. Sapuri and Klufio indicate that conservative treatment is also possible if the following criteria are met: 1. there are no major congenital malformations; 2. the fetus is alive; 3. there is continuous hospitalization in a well-equipped and well-staffed maternity unit which has immediate blood transfusion facilities; 4. there is careful monitoring of maternal and fetal well being; and 5. placental implantation is in the lower abdomen away from the liver and spleen. The choice is largely dictated by the clinical situation. Generally, treatment is indicated when the diagnosis is made; however, the situation of the advanced abdominal pregnancy is more complicated.

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.

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.

The method of delivery is determined by clinical state of the mother, fetus and ultrasound findings. In minor degrees (traditional grade I and II), vaginal delivery is possible. RCOG recommends that the placenta should be at least 2 cm away from internal os for an attempted vaginal delivery. When a vaginal delivery is attempted, consultant obstetrician and anesthetists are present in delivery suite. In cases of fetal distress and major degrees (traditional grade III and IV) a caesarean section is indicated. Caesarian section is contraindicated in cases of disseminated intravascular coagulation. An obstetrician may need to divide the anterior lying placenta. In such cases, blood loss is expected to be high and thus blood and blood products are always kept ready. In rare cases, hysterectomy may be required.

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.

Vasa praevia, also spelled vasa previa, is a condition in which babies' blood vessels cross or run near the internal opening of the uterus. These vessels are at risk of rupture when the supporting membranes rupture, as they are unsupported by the umbilical cord or placental tissue.

Risk factors include in vitro fertilization.

Vasa praevia occurs in about 0.6 per 1000 pregnancies. The term "vasa previa" is derived from the Latin; "vasa" means vessels and "previa" comes from "pre" meaning "before" and "via" meaning "way". In other words, vessels lie before the baby in the birth canal and in the way.

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.

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.

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.

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.

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.

True cervical pregnancies tend to abort; if, however, the pregnancy is located higher in the canal and the placenta finds support in the uterine cavity it can go past the first trimester. With the placenta being implanted abnormally extensive vaginal bleeding can be expected at time of delivery and placental removal. While early cervical pregnancies may abort spontaneously or can be managed with excision, D&C, suturing, electrocautery, and tamponading, by medication such as methotrexate, and/or by uterine artery embolization, a more advanced pregnancy may require a hysterectomy to control bleeding. The more advanced the pregnancy the higher the risk for a major bleeding necessitating a hysterectomy.

On a very rare occasion, a cervical pregnancy results in the birth of a live baby, typically the pregnancy is in the upper part of the cervical canal and manages to extend into the lower part of the uterine cavity.

A cervical pregnancy can develop together with a normal intrauterine pregnancy; such a heterotopic pregnancy will call for expert management as to not to endanger the intrauterine pregnancy.

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.

Circumvallate placenta is a placental morphological abnormalitiy, a subtype of placenta extrachorialis in which the fetal membranes (chorion and amnion) "double back" on the fetal side around the edge of the placenta. After delivery, a circumvallate placenta has a thick ring of membranes on its fetal surface.

The fetal surface is divided into a central depressed zone surrounded by a thickened white ring which is incomplete the ring is situated at varying distance from the margin of the placenta. The ring is composed of a double fold of amnion and chorion with degenerated decidua vera and fibrin in between. Vessels radiate from the cord insertion as far as the ring and then disappear from the view.

Complete circumvallate placenta occurs in approximately 1% of pregnancies. It is diagnosed prenatally by medical ultrasonography, although one 1997 study of prenatal ultrasounds found that "of the normal placentas, 35% were graded as probably or definitely circumvallate by at least one sonologist," and "all sonologists misgraded the case of complete circumvallation as normal." The condition is associated with perinatal complications such as placental abruption, oligohydramnios, abnormal cardiotocography, preterm birth, and miscarriage.

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.

Velamentous cord insertion is an abnormal condition during pregnancy. Normally, the umbilical cord inserts into the middle of the placenta as it develops. In velamentous cord insertion, the umbilical cord inserts into the fetal membranes (choriamniotic membranes), then travels within the membranes to the placenta (between the amnion and the chorion). The exposed vessels are not protected by Wharton's jelly and hence are vulnerable to rupture. Rupture is especially likely if the vessels are near the cervix, in which case they may rupture in early labor, likely resulting in a stillbirth. This is a serious condition called vasa previa. Not every pregnancy with a velamentous cord insertion results in vasa previa, only those in which the blood vessels are near the cervix.

When a velamentous cord insertion is discovered, the obstetrician will monitor the pregnancy closely for the presence of vasa previa. If the blood vessels are near the cervix, the baby will be delivered via cesarean section as early as 35 weeks to prevent the mother from going into labor, which is associated with a high infant mortality. Early detection can reduce the need for emergency cesarean sections.

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.

Obstetrical bleeding also known as obstetrical hemorrhage and maternal hemorrhage, refers to heavy bleeding during pregnancy, labor, or the postpartum period. Bleeding may be vaginal or less commonly but more dangerously, internal, into the abdominal cavity. Typically bleeding is related to the pregnancy itself, but some forms of bleeding are caused by other events.

The most frequent cause of maternal mortality worldwide is severe hemorrhage with 8.7 million cases occurring in 2015 and 83,000 of those events resulting in maternal death. Between 2003 and 2009, hemorrhage accounted for 27.1% of all maternal deaths globally

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.

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.

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.

Some doctors recommend complete bed-rest for the mother coupled with massive intakes of protein as a therapy to try to counteract the syndrome. Research completed shows these nutritional supplements do work. Diet supplementation was associated with lower overall incidence of TTTS (20/52 versus 8/51, P = 0.02) and with lower prevalence of TTTS at delivery (18/52 versus 6/51, P = 0.012) when compared with no supplementation. Nutritional intervention also significantly prolonged the time between the diagnosis of TTTS and delivery (9.4 ± 3.7 weeks versus 4.6 ± 6.5 weeks; P = 0.014). The earlier nutritional regimen was introduced, the lesser chance of detecting TTTS ( P = 0.001). Although not statistically significant, dietary intervention was also associated with lower Quintero stage, fewer invasive treatments, and lower twin birth weight discordance. Diet supplementation appears to counter maternal metabolic abnormalities in monochorionic twin pregnancies and improve perinatal outcomes in TTTS when combined with the standard therapeutic options. Nutritional therapy appears to be most effective in mitigating cases that are caught in Quintero Stage I, little effect has been observed in those that are beyond Stage I.