Selected Childbirth Complications

This section presents information on selected labor and birth complications, including preterm and postterm birth, preterm premature rupture of membranes, infections, dystocia, induction/augmentation of labor, and vaginal birth after cesarean. Assisted births, including cesarean birth and forceps- or vacuum-assisted vaginal births, are also addressed. Finally, information on managing selected emergency situations, meconium-stained amniotic fluid, shoulder dystocia, and prolapsed umbilical cord, is included.

Preterm Labor and Birth

Preterm labor is defined as cervical changes and uterine contractions occurring between 20 and 37 weeks of pregnancy. Preterm birth is any birth that occurs before the completion of 37 weeks of pregnancy. About 75% of all preterm births in the United States are termed late preterm births because they occur between 34 and 36 weeks of gestation. The steady increase in the preterm birth rate has been attributed to the rise in the rate of late preterm births, which has increased 25% since 1990.

Etiology

Increasingly, preterm births are being divided into two categories, spontaneous and indicated. Spontaneous preterm births occur following an early initiation of the labor process and comprise nearly 75% of all preterm births in the United States. Box 4-1 lists risk factors for spontaneous preterm labor.

BOX 4-1

Risk Factors for Spontaneous Preterm Labor

Genital tract infection

Non-Caucasian race

Multifetal gestation

Second-trimester bleeding

Low prepregnancy weight

History of previous spontaneous preterm birth

Source: Iams, J., Romero, R., & Creasy, R. (2009). Preterm labor and birth. In R. Creasy, R. Resnik, J. Iams, C. Lockwood, & T. Moore (Eds.), Creasy and Resnik’s maternal-fetal medicine: Principles and practice (6th ed.). Philadelphia: Saunders.

Indicated preterm births, on the other hand, occur as a means to resolve maternal or fetal risk related to continuing the pregnancy. About 25% of all preterm births in the United States are indicated because of medical or obstetric conditions that affect the mother, the fetus, or both. An increase in the number of indicated preterm births accounts for much of the rise in late preterm births. Box 4-2 lists common causes of indicated preterm birth.

BOX 4-2

Common Causes of Indicated Preterm Birth

Preeclampsia

Fetal distress

Intrauterine growth restriction

Placental abruption

Intrauterine fetal demise

Pregestational and gestational diabetes

Renal disease

Rh sensitization

Congenital malformations

Predicting Preterm Labor and Birth

Major risk factors for spontaneous labor and birth include:

History of previous preterm birth

Multiple gestation

Bleeding after the first trimester of pregnancy

Low maternal body mass index (BMI)

Other risk factors for spontaneous labor and birth include

Non-Caucasian race

Low socioeconomic status

Low educational status

Living with chronic stress

Domestic violence

Lack of social support

Smoking

Substance abuse

Physically demanding working conditions

Periodontal disease

At least 50% of all women who ultimately give birth prematurely, however, have no identifiable risk factors.

Biochemical marker

Fetal fibronectin—Glycoprotein found in plasma and produced during fetal life. Fetal fibronectin normally appears in cervical and vaginal secretions early in pregnancy, and then again in late pregnancy.

The presence of fetal fibronectin during the late second and early third trimesters may be related to placental inflammation, which is thought to be one cause of spontaneous preterm labor. The presence of fetal fibronectin is not very sensitive as a predictor of preterm birth, however. Often the test is used to predict who will not go into preterm labor, because preterm labor is very unlikely to occur in women with a negative result.

The test is performed by collecting fluid from the woman’s vagina using a swab during a speculum examination.

Endocervical length

A shortened cervix as determined by ultrasound measurement may precede preterm labor. Changes in cervical length occur before uterine activity, so cervical measurement can identify women in whom the labor process has begun. However, because preterm cervical shortening occurs over a period of weeks, neither digital nor ultrasound cervical examination is very sensitive at predicting imminent preterm birth. Women whose cervical length is more than 30 mm are unlikely to give birth prematurely even if they have symptoms of preterm labor.

Management

Pregnancy

Teach all pregnant women the early signs and symptoms of preterm labor listed in Box 4-3 and what to do if they occur. (See the Teaching for Self-Management box: What to Do if Symptoms of Preterm Labor Occur.) In particular, education regarding any symptoms of uterine contractions or cramping

Teaching for Self-Management

What to Do if Symptoms of Preterm Labor Occur

Empty your bladder.

Drink two to three glasses of water or juice.

Lie down on your side for 1 hr.

Palpate for contractions.

If symptoms continue, call your health care provider or go to the hospital.

If symptoms go away, resume light activity, but not what you were doing when the symptoms began.

If symptoms return, call your health care provider or go to the hospital.

If any of the following symptoms occur, call your health care provider immediately:

Uterine contractions every 10 min or less for 1 hr or more

Vaginal bleeding

Odorous vaginal discharge

Fluid leaking from the vagina

between 20 and 27 weeks of gestation must emphasize that these symptoms are not just normal discomforts of pregnancy, but rather indications of possible preterm labor.

BOX 4-3

Signs and Symptoms of Preterm Labor

Uterine Activity

Uterine contractions occurring more frequently than every 10 min persisting for 1 hr or more

Contractions may be painful or painless

Discomfort

Lower abdominal cramping similar to gas pains; may be accompanied by diarrhea

Dull, intermittent low back pain (below the waist)

Painful, menstrual-like cramps

Suprapubic pain or pressure

Pelvic pressure or heaviness; feeling that “baby is pushing down”

Urinary frequency

Vaginal Discharge

Change in character or amount of usual discharge: thicker (mucoid) or thinner (watery), bloody, brown or colorless, increased amount, odor

Rupture of amniotic membranes

If symptoms of preterm labor occur with sexual activity, the woman should be counseled about lifestyle modification until she reaches 37 weeks of gestation.

Bed rest is frequently prescribed, but there is no evidence in the literature to support the effectiveness of this intervention in reducing preterm birth rates. Therefore, many health care providers now recommend only modified bed rest in which women are usually allowed bathroom privileges for toileting and showering and can be up to the table for meals.

Intrapartum

The diagnosis of preterm labor requires all of the following:

Gestational age between 20 and 37 weeks

Uterine activity (contractions)

Progressive cervical change (effacement of 80% or greater or cervical dilation of 2 cm or greater)

If preterm labor is diagnosed, the woman will be admitted to the hospital for tocolytic therapy, medications to suppress uterine activity in an attempt to prevent preterm birth. Research has demonstrated that prolonging the pregnancy 48 hours to several days is the best outcome that can be expected. The purposes of tocolytic therapy are to gain time for administering antenatal corticosteroids and transporting the mother to a facility with a neonatal intensive care unit.

There is no clear first-line tocolytic drug. Medications commonly used for tocolytic therapy include the following:

Magnesium sulfate

Terbutaline (Brethine)

Nifedipine (Adalat, Procardia)

Indomethacin (Indocin)

See the Medication Guide in Appendix B for information on these medications.

Antenatal glucocorticoids (betamethasone, dexamethasone), given as intramuscular injections to the mother to accelerate fetal lung maturity by stimulating fetal surfactant production, are considered one of the most effective and cost-efficient interventions for preventing neonatal morbidity and mortality associated with preterm labor. Antenatal glucocorticoids have been shown to significantly reduce the incidence of respiratory distress syndrome, intraventricular hemorrhage, necrotizing enterocolitis, and death in neonates, without increasing the risk of infection in mothers or newborns. All women between 24 and 34 weeks of gestation should be given a single course of antenatal glucocorticoids when preterm birth is threatened unless evidence indicates that glucocorticoids will have an adverse effect on the mother or birth is imminent. Because optimal benefit begins 24 hours after the first injection, timely administration is essential. (See the Medication Guide: Antenatal Glucocorticoid Therapy with Betamethasone, Dexamethasone in Appendix B.)

Management of inevitable preterm birth

Once the cervix dilates to 4 cm or more, preterm birth is likely.

If preterm birth appears inevitable, transfer the woman before birth, if possible, to a facility equipped to care for the infant. Give the first dose of antenatal corticosteroids before transfer.

Monitor for rapid progression to birth. Remember that very tiny preterm infants may pass through a cervix that has not completely dilated.

Gather equipment, supplies, and medications used for neonatal resuscitation in advance and prepare them for immediate use.

Have personnel skilled in neonatal resuscitation present during the birth.

If birth occurs in a hospital that is not prepared to provide continuing care for a preterm neonate, make plans for immediate transfer of the infant to a higher level of care.

Nursing Considerations

Because at least 50% of all women who give birth prematurely have no identifiable risk factors, all pregnant women must be educated about signs and symptoms of preterm labor.

If the fetal fibronectin test is used, a sample of vaginal fluid for testing must be obtained before a vaginal examination for cervical changes is performed. The lubricant used during the vaginal examination can reduce the accuracy of the fetal fibronectin test. The presence of vaginal bleeding or ruptured membranes, or a history of intercourse within the past 24 hours can also reduce the accuracy of the test results.

Preterm Premature Rupture of Membranes

Premature rupture of membranes (PROM) is the rupture of the amniotic sac and leakage of amniotic fluid beginning before the onset of labor at any gestational age. In preterm premature rupture of membranes (preterm PROM) rupture of the amniotic sac occurs before 37 weeks of gestation. The woman may complain of either a sudden gush or a slow leak of fluid from the vagina.

Etiology

Preterm PROM most likely results from pathologic weakening of the amniotic membranes caused by inflammation, stress from uterine contractions, or other factors that cause increased intrauterine pressure. Infection of the urogenital tract is a major risk factor associated with preterm PROM.

Risks Associated with Preterm PROM

Postterm Pregnancy

A postterm pregnancy (also sometimes referred to as a postdate or prolonged pregnancy) is one that extends beyond the end of week 42 of gestation, or 294 days from the first day of the last menstrual period (LMP). The incidence of postterm pregnancy is estimated to be between 4% and 14% (Resnik & Resnik, 2009). Many pregnancies are misdiagnosed as prolonged because of inaccurate dating.

Etiology

The exact cause of true postterm pregnancy is not known. However, it is clear that the timing of labor is determined by complex interactions among the fetus, the placenta and membranes, the uterine myometrium, and the cervix.

Risk Factors for Postterm Pregnancy

First pregnancy

History of previous postterm pregnancy

Presence of congenital primary fetal adrenal hypoplasia or placental sulfatase deficiency

Clinical Manifestations

Maternal weight loss (more than 3 lb/wk)

Decreased uterine size (related to decreased amniotic fluid volume)

Meconium-stained amniotic fluid

Advanced bone maturation of the fetal skeleton with an exceptionally hard fetal skull

Maternal Risks

Perineal injury (related to fetal macrosomia)

Hemorrhage

Infection

Labor induction

Forceps- or vacuum-assisted birth

Cesarean birth

Feelings of depression, frustration, and inadequacy

Fetal Risks

Abnormal fetal growth

Macrosomia (more than 4000 g) (more likely)

Small for gestational age

Postmaturity syndrome

Meconium aspiration syndrome

Management

The management of postterm pregnancy is still controversial. However, because perinatal morbidity and mortality increase greatly after 42 weeks of gestation, pregnancies are usually not allowed to continue after this time.

In the United States, most physicians induce labor at 41 weeks of gestation. During labor the fetus of a woman with a postterm pregnancy should be continuously monitored electronically for a more accurate assessment of the FHR and pattern.

An alternative approach for managing postterm pregnancy is to initiate twice-weekly fetal testing at 41 weeks of gestation. The testing generally consists of either a BPP or NST along with an assessment of amniotic fluid volume. In addition, the woman is encouraged to assess fetal activity daily, assess for signs of labor, and keep appointments with her primary health care provider.

Evidence is insufficient to determine which of the two management approaches described above is better.

Nursing Considerations

The woman and her family should be encouraged to express their feelings (e.g., frustration, anger, impatience, fear) about the prolonged pregnancy and helped to realize that these feelings are normal. At times the emotional and physical strain of a postterm pregnancy may seem overwhelming. Referral to a support group or another supportive resource may be needed.

Infections

Maternal Group B Streptococci (GBS) Infection

May be considered part of the normal vaginal flora in women who are not pregnant

Present in about 20% to 30% of healthy pregnant women

Diagnosis

Made by screening all pregnant women at 35 to 37 weeks of gestation using a rectovaginal culture

Management

All women with a positive culture result should receive intravenous antibiotic prophylaxis (IAP) during labor

Women with an unknown GBS status (i.e., culture was not done or results are unknown) should also receive IAP if any of the following risk factors are present:

Less than 37 weeks of gestational age

Fever greater than 38.0° C (100.4° F)

Ruptured membranes for more than 18 hours

History of previous infant with GBS infection

GBS-positive urine culture during current pregnancy

Be aware that some practitioners give IAP during labor to all women with an unknown GBS status, even if none of the risk factors listed above are identified.

Accurate rapid polymerase chain reaction (PCR) testing is available for use in women who are admitted with an unknown GBS status to give birth.

Ampicillin, 2-g loading dose IV followed by 1 g IV every 4 hours during labor

Women who are allergic to penicillin may be treated with cefazolin (Ancef), clindamycin (Cleocin), erythromycin, or vancomycin (Vancocin)

IAP is not necessary before planned cesarean births if the woman is not in labor and the membranes have not ruptured.

Maternal and Newborn Effects

Most women are asymptomatic. GBS can, however, cause urinary tract infection, chorioamnionitis, or endometritis. Sepsis and meningitis are very rare complications of GBS infection.

In newborns the major risk is for early-onset infection. The practice of giving prophylactic antibiotics to women in labor who are GBS positive has significantly reduced the incidence and severity of early-onset GBS infection in the newborn.

Chorioamnionitis

Chorioamnionitis, bacterial infection of the amniotic cavity, is a major cause of complications for mothers and newborns at all gestational ages. Chorioamnionitis is usually caused when organisms that are part of the normal vaginal flora ascend into the amniotic cavity.

Other terms for this condition include clinical chorioamnionitis, amnionitis, intrapartum infection, amniotic fluid infection, and intraamniotic infection.

Diagnosis

Chorioamnionitis is usually diagnosed by the clinical findings of maternal fever, maternal and fetal tachycardia, uterine tenderness, and foul-smelling amniotic fluid.