A pregnancy that ends as a result of natural causes before fetal viability is defined as a miscarriage (spontaneous abortion). Spontaneous abortion is a loss that occurs before 20 weeks of gestation. Fetal weight less than 500 g also may be used to define an abortion. The term miscarriage rather than abortion is used throughout this discussion because it is more appropriate to use with clients. 

Incidence and Etiology 

Greater than 80% of miscarriages are early pregnancy losses, occurring before 12 weeks of gestation and are not clinically recognized. In many cases the woman does not realize that she is pregnant. Half of all miscarriages are chromosomally normal, while the other half have a chromosomal abnormality. 

Other possible causes of miscarriage include: 

• Various medical disorders (e.g., poorly controlled diabetes mellitus, obesity, thyroid disease, and systemic lupus erythematosus) 

• Regular and heavy alcohol consumption 

• Excessive (>500 mg/day) caffeine intake 

• Environmental toxins 

• Increasing paternal age 

Infections, however, are not a common cause of miscarriage.  

Assessment

Data to be collected include:

• Pregnancy history 

• Vital signs 

• Type and location of pain 

• Quantity and nature of bleeding 

• Emotional status
  
  

Laboratory tests may include: 

• Evaluation of human chorionic gonadotropin (β-hCG) (pregnancy hornome) - this number should double every 48 hours in a healthy pregnancy.  A decrease in the value would indicate a non-viable pregnancy.

• Hemoglobin level (anemia) 

• White blood cell count (infection)

Initial Care 

• Management depends on the classification of the miscarriage and on signs and symptoms. 

• Follow-up treatment depends on whether the threatened miscarriage progresses to actual miscarriage or symptoms subside and the pregnancy remains intact. If bleeding and infection do not occur, observation is implemented. Acetaminophen-based analgesia may be given to relieve pain from cramping.

• Once the cervix begins to dilate, the pregnancy cannot continue and miscarriage becomes inevitable. If all the products of conception are passed, no surgical intervention is necessary. If heavy bleeding, excessive cramping, or infection is present, however, the remaining embryonic, fetal, or placental tissue must be removed from the uterus, usually by suction curettage (surgical management). In women who are clinically stable, expectant management of an incomplete miscarriage to allow spontaneous resolution or medical management using the prostaglandin misoprostol (Cytotec) administered orally or vaginally are other treatment options.  Misoprostol can only be used if the pregnancy is 8 weeks of gestation or less

• Most missed miscarriages eventually end spontaneously, although weeks may pass between the diagnosis of a failed pregnancy and spontaneous miscarriage. Medical management is less invasive, more bleeding, longer completion times, and lower success rates are associated with this option, compared with surgical management. If medical management is chosen, nursing care is similar to the care for any woman whose labor is induced.

• A surgical management option, one that is often chosen, is dilation and curettage (D&C), a procedure in which the cervix is dilated if necessary and uterine contents are removed by suction curettage using a catheter attached to an electric-powered vacuum source. Postoperative care includes recovery from anesthesia, pain management, and discharge instructions.

• After evacuation of the uterus, oxytocin is often given to prevent hemorrhage. For excessive bleeding after the miscarriage, ergot products such as ergonovine (Methergine) or a prostaglandin derivative such as methyl carboprost tromethamine (Hemabate) are used.

• Antibiotics are given as necessary. Analgesics, such as antiprostaglandin agents (e.g., nonsteroidal anti-inflammatory drugs [NSAIDs]), may decrease discomfort from cramping. Transfusion therapy may be required for shock or anemia. The woman who is Rh negative and is not isoimmunized is given Rho(D) immune globulin.

• Follow-up Care 

• The woman will likely be discharged home within a few hours after a D&C or as soon as her vital signs are stable, vaginal bleeding remains minimal, and she has recovered from anesthesia. Discharge teaching emphasizes the need for rest.

• If significant blood loss has occurred, iron supplementation may be ordered. 

• Teaching includes information about normal physical findings, such as cramping, type and amount of bleeding, resumption of sexual activity, and family planning. Frequently the woman and her partner want to know when she should attempt to become pregnant again. 

• Follow-up care should assess the woman’s emotional as well as physical recovery 

Clinical Manifestations 

Signs and symptoms of miscarriage depend on the duration of pregnancy and may include: 

• Presence of uterine bleeding 

• Uterine contractions 

• Abdominal pain  

If miscarriage occurs before the sixth week of pregnancy, the woman may report what she believes is a heavy menstrual flow. Miscarriage that occurs between weeks 6 and 12 of pregnancy causes moderate discomfort and blood loss. After week 12, miscarriage is typified by severe pain, similar to that of labor, because the fetus must be expelled.  

Diagnosis and management of miscarriage is based on the signs and symptoms present.

Recurrent (habitual) miscarriage is classically defined as three or more spontaneous pregnancy losses before 20 weeks of gestation or with a fetal weight of less than 500 g. Most widely accepted causes of recurrent miscarriage are parental chromosomal abnormalities, antiphospholipid antibody syndrome, and certain uterine abnormalities. 

Evaluation of couples experiencing recurrent pregnancy loss usually includes: 

• Karyotyping of both partners and miscarriage specimens and assessment of the placenta 

• Evaluating the woman’s uterine cavity 

• Screening for abnormalities of prolactin and thyroid disease 

• Psychological response to this diagnosis, because women and their partners often report feelings of guilt, anxiety, and depression 

Miscarriages can become septic, although this is uncommon. Symptoms of a septic miscarriage include fever and abdominal tenderness. Vaginal bleeding, which may be slight to heavy, is usually malodorous. 

One cause of late miscarriage is cervical insufficiency. This traditionally has been defined as passive and painless dilation of the cervix leading to recurrent preterm births during the second trimester in the absence of other causes.  Measurement of cervical length has been used as a way to diagnose cervical insufficiency. It is now known that an abnormally short cervix identified during the second trimester can also represent an early step in the process of preterm labor. The challenge is to identify women who have cervical changes because of impaired cervical strength before conception or in early pregnancy rather than when preterm labor begins.  Assessment of cervical function to diagnose or rule out cervical insufficiency can be done only during pregnancy.

Cerclage is removed if preterm prelabor rupture of membranes or advanced preterm labor that puts pressure on the stitch occurs. If the pregnancy progresses without further complications, the cerclage is removed when the woman reaches 36 weeks of gestation. The only indication for an abdominal cerclage that has been proven to be of benefit is failure of a prior history-indicated transvaginal cerclage, where spontaneous preterm birth occurred before 33 weeks of gestation. The procedure is usually done at 11 to 12 weeks of gestation or before conception by means of a laparotomy.

Follow-up Care 

Decisions about physical activity and intercourse are individualized, based on the status of the woman’s cervix, as determined by digital and ultrasound examination. Instruction includes the need to watch for and report signs of preterm labor, rupture of membranes, and infection. 

Know the signs that would warrant an immediate return to the hospital: 

• Strong contractions less than 5 minutes apart 

• Preterm labor or rupture of membranes 

• Severe pelvic pressure 

• Urge to push through the pelvis

Premature separation of the placenta, or abruptio placentae, is the detachment of part or all of a normally implanted placenta from the uterus. Separation occurs in the area of the decidua basalis after 20 weeks of gestation and before the birth of the infant. 

Incidence and Etiology 

• Maternal hypertension, whether chronic or pregnancy related, is the most consistently identified risk factor for abruption.  

• Cocaine use is also a risk factor because it causes vascular disruption in the placental bed. Blunt external abdominal trauma, most often the result of motor vehicle accidents (MVAs) is also a cause. Maternal battering, is another frequent cause of placental abruption.

• Other risk factors include: 

  • • Cigarette smoking 

    • History of abruption in a previous pregnancy 

    • Preterm prelabor rupture of membranes

    • Perhaps thrombophilic disorders and abruption 

    • Twin gestations

    • Women who have had two previous abruptions

Laboratory findings include: 

• Positive apt test result (blood in the amniotic fluid) 

• Decrease in hemoglobin and hematocrit levels 

• Decrease in coagulation factor levels 

• Clotting defects (e.g., disseminated intravascular coagulation) may be present 

• Kleihauer-Betke (KB) test may be ordered to determine the presence of fetal-to-maternal bleeding (transplacental hemorrhage), although it is of no diagnostic value 

  • KB test may be useful, however, to guide Rho(D) immune globulin therapy in Rh-negative women who have had an abruption

Management

Expectant Management 

• Management depends on the severity of blood loss and fetal maturity and status. If the fetus is between 20 and 34 weeks of gestation and both the woman and fetus are stable, expectant management can be implemented.  

• The woman is monitored closely because the abruption may extend at any time. The fetus is assessed regularly for evidence of appropriate growth because there is risk for IUGR. Assessments of fetal well-being (e.g., nonstress testing, biophysical profile) are performed.

Active Management 

• Immediate birth is the management of choice if the fetus is at term gestation or the bleeding is moderate to severe and the mother or fetus is in jeopardy. At least one large-bore (16- to 18-gauge) IV line should be inserted. 

• Maternal vital signs are monitored frequently to observe for signs of declining hemodynamic status, such as increasing pulse rate and decreasing blood pressure. 

• Serial laboratory studies include: 

  • • Hematocrit or hemoglobin determinations 

    • Clotting studies 

• Continuous EFM is mandatory. Indwelling catheter is inserted for continuous assessment of urine output. Fluid volume replacement may be necessary. There should be administration of blood products to correct any coagulation defects. 

Outcomes

Maternal Outcomes 

• The mother’s prognosis depends on: 

  • • Extent of placental detachment 

    • Overall blood loss 

    • Degree of coagulopathy present 

    • Time that passes between placental detachment and birth 

• Maternal complications are associated with the abruption or its treatment: 

  • • Hemorrhage 

    • Hypovolemic shock 

    • Hypofibrinogenemia 

    • Thrombocytopenia

    • Renal failure and pituitary necrosis may result from ischemia.

    • In rare cases, women who are Rh negative can become sensitized if fetal-to-maternal hemorrhage occurs and the fetal blood type is Rh positive. 

Fetal Outcomes

• Fetal complications are related to the severity and timing of the hemorrhage and include: 

  • • IUGR 

    • Oligohydramnios 

    • Preterm birth 

    • Hypoxemia 

    • Stillbirth 

• Fetal survival is related to the size of the hemorrhage. Retroplacental hemorrhages have been associated with a fetal mortality rate of 50%. Neonatal deaths are also common following placental abruption. Morbidity, including cerebral palsy, is common in surviving infants. 

• There is normally a delicate balance (homeostasis) exists between the opposing hemostatic and fibrinolytic systems. Hemostatic system stops the flow of blood from injured vessels, first by a platelet plug, then by the formation of a fibrin clot. Coagulation process involves an interaction of the coagulation factors that constantly circulate in the bloodstream. Each factor sequentially activates the factor next in line (the “cascade effect” sequence). 

• Fibrinolytic system is the process through which the fibrin clot is split into fibrinolytic degradation products and circulation is restored. 

• Disseminated intravascular coagulation (DIC), sometimes called consumptive coagulopathy or defibrination syndrome, is an acquired syndrome characterized by intravascular activation of coagulation which is widespread, rather than localized, and results in excessive clot formation and hemorrhage.

• DIC is never a primary diagnosis. It results from some event that triggered coagulation.  

• Tissue factor (a glycoprotein found in body organs containing many blood vessels, such as the brain, lungs, and placenta, and in amniotic fluid) activates circulating clotting factors when it is released from damaged tissues. This eventually results in the widespread formation of fibrin clots within blood vessels.  

Care Management

Medical management in all cases of DIC involves correction of the underlying cause (e.g., removal of an abrupted placenta or the dead fetus or treatment of existing infection or preeclampsia/eclampsia):

• Volume expansion 

• Rapid replacement of blood products and clotting factors 

• Optimization of oxygenation 

• Achievement of normal body temperature 

• Continued reassessment of laboratory parameters

• Vitamin K administration 

• Recombinant activated factor VIIa 

• Fibrinogen concentrate 

• Hemostatic agents

Interventions

• Assessment for signs of bleeding and complications from the administration of blood products 

• Administering fluid or blood products as ordered 

• Protecting the woman from injury 

Renal failure is one consequence of DIC; urinary output is closely monitored by using an indwelling catheter. Urinary output must be maintained at more than 30 mL/h. 

Vital signs are assessed frequently. If DIC develops before birth, continuous EFM is necessary. The woman should be maintained in a side-lying tilt to maximize blood flow to the uterus. Oxygen may be administered through a nonrebreather face mask at 10 L/min. DIC usually is “cured” with the birth and as coagulation abnormalities resolve.