Editors: Evans, Arthur T.Title: Manual of Obstetrics, 7th EditionCopyright ©2007 Lippincott Williams & Wilkins> Table of Contents > I - Obstetric Care > 1 - Prenatal Care

Prenatal CareArthur T. EvansH. Willette Le Hew

Key Points Prenatal care is designed to provide preventive care and active intervention for acute

medical problems for two interdependent patients. Advances in technology have allowed the fetus to become a separate and distinct patient.

Patient education about pregnancy issues is as important as medical management during prenatal care.

Background Prenatal care is unique:

o It provides care simultaneously to two interdependent patients.

o It is one of the few health care programs that focuses on preventive care and that is recognized and funded by virtually all payers.

There are many components of prenatal care:

o Confirming the diagnosis of pregnancy and establishing the estimated gestational age, which allows the estimated date of confinement to be accurately assigned.

o Obtaining a full history and conducting a physical examination with laboratory evaluation.

o Conducting regular periodic examinations with ongoing patient education.

o Meeting routine health care needs over the length of the pregnancy, solving acute medical problems, and identifying and addressing pregnancy complications.

All information obtained should be recorded in a concise manner that is accessible to other members of the health care team. It is helpful to use a standardized format for charting so that important factors are not overlooked.

Diagnosis of Pregnancy and Accurate Dating The diagnosis of pregnancy and accurate dating are essential to avoid risks during the

first weeks of gestation and for handling possible medical complications, premature labor, or postdates pregnancy.

The diagnosis of pregnancy is facilitated by both presumptive and probable signs.

o Presumptive signs lead a woman to believe that she is pregnant.

o Probable signs are highly suggestive of the diagnosis of pregnancy.

o Note that these signs do not differentiate between an ectopic and an intrauterine pregnancy.

Presumptive Signs Amenorrhea is often the first sign of possible conception. It must be regarded with

caution, however, because lack of menses may result from other factors, such as anovulation, stress, chronic disease, or lactation.

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Subjective signs and symptoms of early pregnancy include breast fullness and tenderness, skin changes, nausea, vomiting, urinary frequency, and fatigue.

Between 12 and 20 weeks' gestation, a woman will note an enlarging abdomen and perceive fetal movement.

Probable Signs Uterine enlargement Softening of the uterine isthmus (Hegar sign)

Vaginal and cervical cyanosis (Chadwick sign)

Pregnancy tests:

o Urine pregnancy tests used today are very sensitive and may be positive as early as 1 week after embryo implantation or within days of the first missed menstrual period. The first voided morning urine is the most concentrated specimen for analysis.

o Radioimmunoassay for serum testing of the beta subunit of human chorionic gonadotropin (hCG) may be accurate up to a few days after implantation (or even before the first missed period). Human chorionic gonadotropin production is at it's maximum oct between 60 and 70 days of gestation and declines thereafter.

o These tests do not differentiate between trophoblastic disease (e.g., molar pregnancy or choriocarcinoma) and normal pregnancy.

o Other bioassay techniques used in the past, such as progesterone withdrawal, are of historic interest only. Progestin should not be given to a woman presumed to be pregnant because of potential (although rare) fetal anomalies (especially limb defects).

Positive Diagnostic Signs Fetal heart tones can be detected as early as 9 to 10 weeks from the last menstrual period

(LMP) by Doppler technology. The nonelectronic fetoscope detects fetal heart tones at 18 to 20 weeks from the LMP.

Fetal movements (“quickeningâ€) are first felt by the patient at approximately 16 to 18� weeks. They are a valuable indication of fetal well-being. Bowel activity often simulates fetal movements and may be confusing to the patient.

Ultrasound examination will demonstrate an intrauterine gestational sac at 5 to 6 weeks and a fetal pole with movement and cardiac activity at 6 to 8 weeks. Vaginal probe

ultrasonography has made these early measurements even more accurate. Fetal age can be estimated by crown–rump length, and the number of fetuses may be identified. Between 8 and 14 weeks of gestation, the fetal measurements, including biparietal diameter and femur length, can be used to estimate fetal age accurately. In the second trimester, fetal anatomy, placental location, and amniotic fluid volume can be evaluated. To date, there is no proof that diagnostic ultrasound exposure has adverse effects on the developing human fetus.

Estimated Date of Confinement The mean duration of pregnancy as calculated from the LMP is 280 days, or 40 weeks. Nägele's rule is used to calculate the estimated date of confinement (EDC):

o To the first day of the LMP, add 7 days and then subtract 3 months.

o Deviations from this calculation may be made for various reasons (e.g., irregular or prolonged menstrual cycles or a know single sexual exposure).

o If the date of the LMP is unknown or does not correlate with uterine size at the first visit, ultrasonography should be used to establish the EDC.

EvaluationA complete history and physical examination are performed after the diagnosis of pregnancy

is established. An important goal is to develop a trusting, working relationship between the patient and the health care team.P.5

History Menstrual and contraceptive history:

o Reliable menstrual history is the most accurate predictor of delivery date.

o Women with recent birth control pill usage may have postpill amenorrhea, and therefore pregnancy dating may be in error.

o Intrauterine device use should be noted, and its presence, absence, or removal carefully documented.

Gynecologic history: Previous gynecologic infections or problems should be recorded.

Obstetric history:

o The obstetric history is recorded as gravidity and parity. Gravidity is the total number of pregnancies. Parity is expressed as four serial numbers: term deliveries, premature deliveries, abortions (spontaneous and elective), and living children.

o Details of previous pregnancies, such as character and length of labor, type of delivery, complications, infant status, and birth weight, should be noted.

Recurrent first-trimester losses or history of second-trimester losses may suggest genetic problems or incompetent cervix.

o If the patient has had a cesarean delivery, recommendations about vaginal birth after cesarean delivery can be addressed at this time.

Medical and surgical history and prior hospitalizations:

o Pre-exsiting medical problems or diagnoses are important for risk assessment and management.

o Previous surgeries and hospitalizations should be elicited and evaluated.

Environmental exposures, medications taken in early pregnancy, reactions to medications, legal and illegal drug use, allergic history, and diethylstilbestrol (DES) exposure.

Family history of medical illnesses, hereditary illness, congenital anomalies, and multiple gestation.

Social factors:

o Home situation, family and social support, and history of possible physical or mental abuse should be assessed and appropriate referrals made.

o Accurate history of substance use is not always easily obtained. Use of legal substances such as cigarettes and alcohol, as well as illicit substance use, is pervasive in all social and racial groups. All of these chemicals have serious ramifications for fetal development and pregnancy outcome.

Review of systems as related to pregnancy: nausea, vomiting, abdominal pain, constipation, headaches, syncopal episodes, vaginal bleeding or discharge, dysuria or urinary frequency, swelling, varicosities, and hemorrhoids.

Physical Examination Complete physical examination with attention to specific organ systems as directed by

any positive findings in the history:o Measurement of height, weight, blood pressure, pulse; funduscopic examination;

examination of thyroid, lymph nodes, lungs, heart, breasts, and abdomen, with fundal height and presence of fetal heart tones, extremities; and a basic neurologic screening.

o Evaluate the normal changes found in pregnancy as well as the pathologic changes that may develop during pregnancy to properly assess the findings of the physical examination.

Pelvic examination:

o External genitalia—evidence of previous obstetric injury should be noted.

o Vagina—under hormonal influence of pregnancy, cervical secretions are increased, thus raising the vaginal pH, which may cause a change in the bacteriologic flora of the vagina. No treatment is necessary unless diagnosis of a specific infection is made (see “Treatment of Common Lesions and Infections†later in this chapter). Screening for bacterial vaginosis should be� done in women at high risk for premature labor.

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o Cervix—A Papanicolaou test and culture for gonorrhea are routinely performed unless the Papanicolaou test has been done recently. A Chlamydia culture should also be performed in high-risk populations.

Cervical softening and eversion (ectropion) is normal.

Nabothian cysts are of no consequence.

Dilatation of the external os is common in multiparous patients and is benign. Effacement or dilation of the internal os is abnormal, except near term, and may indicate premature labor or incompetent cervix.

Morphologic cervical changes (ridges, hood, or collar), or vaginal adenosis may indicate DES exposure in utero. These women have a higher incidence of incompetent cervix and premature delivery and should be evaluated accordingly.

o Uterus—Estimating gestational age by gauging uterine size is one of the most important elements of the first examination.

A normal, nongravid uterus is firm, smooth, and approximately 3 x 4 x 7 cm. The uterus will not change noticeably in consistency or size until 5 to 6 weeks after the LMP, or 4 weeks from conception.

Gestational age from the LMP is estimated by uterine volume (i.e., 8 weeks, twice normal size; 10 weeks, three times normal; 12 weeks, four times normal). At 12 weeks, the uterus fills the pelvis so that the fundus of the uterus is palpable at the symphysis pubis. By 16 weeks, the uterus is midway between the symphysis pubis and the umbilicus. At 20 weeks, it reaches the umbilicus. Thereafter, there is a rough correlation between weeks of gestation and centimeters of fundal curvature when measured from the top of the symphysis pubis to the top of the uterine fundus (MacDonald measurement).

After correcting for minor discrepancies resulting from adiposity and variation in body shape, a uterine size that exceeds the anticipated gestational age by 3 weeks or more, as calculated from the last normal menstrual period, suggests multiple gestation, molar pregnancy, leiomyomata, uterine anomalies, adnexal masses, or simply an inaccurate

date for the LMP. Ultrasonography is the best diagnostic tool for this situation.

Smaller than expected uterine size for gestational age may indicate inaccurate dating, oligohydramnios, or intrauterine growth restriction.

Adnexa are difficult to evaluate because the fallopian tubes and the ovaries are lifted out of the pelvis by the enlarging uterus. Any questionable masses should be confirmed by ultrasonogram.

Clinical pelvimetry is done as part of the initial bimanual exam to assess the general adequacy of the pelvis for vaginal delivery.

o Clinical pelvimetry requires experience and is inherently inaccurate even with a highly experienced examiner.

o Although it is still in use, clinical pelvimetry, in today's obstetric environment, yields too many false-positive and false-negative results to be relied on for clinical decisions.

o Computed tomography (CT) pelvimetry has replaced traditional x-ray pelvimetry for obtaining an objective measurement of pelvic size. There may be situations where CT pelvimetry can provide objective information that contributes to clinical decision making, such as evaluation for vaginal breech delivery.

Laboratory EvaluationA history positive for certain illness or abnormalities in other screening tests should be investigated with further tests as indicated.

A routine initial screen includes a complete blood count, ABO blood typing and Rh factor, antibody screening, urinalysis and culture, serologic test for syphilis, rubella titer, Papanicolaou test, cervical culture for gonorrhea, and hepatitis B surface-antigen screening. A cervical culture for Chlamydia is indicated in high-risk patients.

Group B Streptococcus (GBS) (see Chapter 23):

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o Screening is not indicated in early pregnancy, nor is it based on risk factors.o All pregnant women should be screened for GBS at 35 to 37 weeks' gestation by a

culture obtained from a swab of the rectum and the lower third of the vagina. Patients with positive results are treated with appropriate antibiotics during labor.

o Patients presenting with preterm labor, premature rupture of membranes, or maternal fever in labor for whom no culture results are available should have rectovaginal cultures performed and receive GBS antibiotic treatment until the culture results are available.

Specialized screening tests:

o HIV screening, with appropriate counseling and consent, should be offered to all pregnant women and should be strongly encouraged in high-risk populations.

o Hemoglobin electrophoresis should be used to identify hemoglobinopathies in specific groups of women:

Sickle hemoglobin in African Americans

Beta-thalassemia in Mediterranean couples

Alpha-thalassemia in Asian couples.

o Tay-Sachs carrier status analysis is indicated in Jewish couples.

o Herpes cultures for purposes of screening are not recommended. Cultures may be helpful for confirming diagnosis when active lesions are present; however, they have little value in predicting whether the fetus is at risk.

o Urine or blood toxicology screening may be indicated for the evaluation of illicit substance use in selected patients and situations.

o Fetal ultrasound as a routine screening test without indications is not currently considered a standard of care in uncomplicated pregnancies. However, most physicians consider an obstetric ultrasound examination to be an essential part of prenatal evaluation and care for all pregnant women. Indeed, almost all pregnancies exhibit at least one of the indications for ultrasound examination.

o Down syndrome screening can be offered in the first trimester at 10 to 14 weeks' gestation through a combination of two serum analytes, pregnancy associated plasma protein-A (PAPP-A) and free β-hCG, and nuchal translucency by ultrasound.

Mid-trimester screening tests:

o Risk assessment for Down syndrome, trisomies 18 and 13, open neural tube defects, ventral wall defects, and a list of other, more rare abnormalities can be accomplished through the Triple or Quad screens. These tests evaluate a combination of serum analytes to arrive at a risk statement rather than a diagnosis. The Quad screen is now the preferred test because the combination of maternal serum (MS)-α-fetoprotein, β-hCG, estriol, and inhibin A provides greater sensitivity. Blood should be drawn between the 15th and 20th weeks of gestation (16 to 18 weeks ispreferred). Abnormal results are further evaluated by ultrasonography and amniocentesis.

o At 24 to 28 weeks, a 1-hour glucola screen (blood glucose measurement 1 hour after a 50-g oral glucose load) is obtained to screen for gestational diabetes.

A 1-hour glucola screen value >140 mg per dl is considered abnormal and requires definitive testing by a 3-hour 100-g oral glucose tolerance test.

A universal screening approach can be used in which all pregnant women are screened.

Alternatively, a screening scheme can be used that excludes women who are at low risk for gestational diabetes by meeting all of the following criteria:

Younger than 25 years of age

Not a member of a racial or ethnic group with high prevalence of gestational diabetes

Body mass index <25

No history of abnormal glucose tolerance

No previous history of adverse pregnancy outcomes usually associated with gestational diabetes

No known diabetes in first-degree relatives.

Women with a particular risk (e.g., previous gestational diabetes or fetal macrosomia) should receive glucola screening early in pregnancy.

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o Repeat hemoglobin and hematocrit are obtained at 26 to 30 weeks to determine whether iron supplementation is needed.

o Repeat serologic testing for syphilis is recommended at 28 to 32 weeks for high-risk groups.

o At 28 to 30 weeks, an antibody screen is obtained in Rh-negative women, and an Rho(D) immunoglobulin (RhoGAM) is administered.

o Repeat third-trimester screening for gonorrhea and Chlamydia is recommended in high-risk populations.

Treatment of Common Lesions and Infections that May Be Encountered on Pelvic Examination

Bartholin Gland Abscess A painful, erythematous, cystic enlargement on either side of the lateral vaginal introitus

indicates obstruction and infection of the Bartholin gland. Treatment includes sitz baths, analgesic, and, when fluctuant, incision and drainage. Cyst

formation may result from incomplete resolution of an abscess. Marsupialization after the puerperium may be advisable for recurrent problems.

Condylomata acuminata Venereal warts are hyperkeratotic, flat, or polypoid lesions found in the vulvar or perineal

areas, vagina, or cervix and caused by infection with the human papilloma virus (HPV).

Certain viral types are associated with the development of dysplasia and epithelial carcinoma.

Pregnancy may stimulate proliferation of these lesions, which may become friable. Rarely, cesarean delivery is necessary to prevent extensive vaginal damage at delivery.

There is also an ill-defined risk of transmission of HPV to the infant, with development of laryngeal papillomata. The mode of transmission is unknown, and currently there is no consensus regarding the protective benefit to the newborn of cesarean versus vaginal delivery.

Treatment of the lesions is more difficult in pregnancy. Podophyllin resin, trichloroacetic acid, 5-fluorouracil, and immunotherapy should be avoided. However, cryotherapy, electrocauterization, or laser may be used on external lesions.

Herpes Simplex Viral Infections Characteristic lesions are small, painful, superficial, erythematous vesicles that ulcerate. Treatment is symptomatic. The use of the antiviral agents acyclovir, amcyclovir, and

valacyclovir has not been approved but has been reported. Such treatment should be considered only on an individual risk–benefit basis.

If lesions are present at the time of labor or rupture of membranes, cesarean delivery should be performed.

Monilial Vulvovaginitis Monilial (also known as candida or yeast) infection with the characteristic curdy, white,

itchy discharge is common. Hyphal structures are seen on wet mount. This infection can be treated safely during pregnancy with nystatin or miconazole nitrate

creams or suppositories in the usual dose regimens. Fluconazole (Diflucan) should be used only in life-threatening situations.

Trichomonas vaginalis Infection Vulvar or vaginal burning or itching with a frothy, malodorous discharge is a frequent

finding with this infection. Confirmation of the diagnosis is by visualization of the organisms on wet mount.

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Metronidazole (Flagyl) is the treatment of choice but is contraindicated during the first trimester because of possible teratogenicity. Clotrimazole suppositories (one nightly for 1 week) have been used, with an improvement in symptoms and a 70% cure rate. For severe cases, metronidazole may be used during the second and third trimesters, but the 2-g dose should be avoided. The sexual partner should also be treated.

Bacterial Vaginosis

Also referred to as Gardnerella vaginalis or Haemophilus vaginalis vaginitis, bacterial vaginosis produces a white to gray malodorous discharge that is mildly irritating. Characteristic clue cells are noted on wet mount, with amine discharge on potassium hydroxide preparation.

The current drug of choice is metronidazole, but its use is restricted in pregnancy, as discussed above. Ampicillin, 500 mg for 7 days, may be used. In the second and third trimesters, treatment with metronidazole, 500 mg by mouth, twice a day for 5 to 7 days, may be used. Treatment of the sexual partner has not been found to be useful in routine cases.

Some studies have suggested an association between bacterial vaginosis and preterm labor risk, but this association remains uncertain.

Neisseria gonorrhoeae Infection Symptoms may include dysuria, burning, or only vaginal or cervical discharge. Many

patients are asymptomatic. Microscopically, gram-negative intracellular diplococci are seen in the discharge, but culture confirmation is imperative.

Usual treatment regimens may be administered; however, tetracycline is contraindicated in pregnancy. The sexual partner should be treated and a test-of-cure culture obtained after treatment.

Because of the high rate of coexistent infection, it is recommended that women with gonorrheal infection be treated for Chlamydia (see below).

Chlamydia trachomatis Infection Symptoms of the infection from this obligatory intracellular parasite range from

asymptomatic to cervicitis, discharge, and discomfort. Diagnosis is made by special culture; in some areas more rapid tests are available.

The infection can be passed to the newborn in the form of conjunctivitis or pneumonia.

Treatment is erythromycin, 250 to 500 mg by mouth, four times per day for 10 to 14 days. Tetracycline is effective but it is contraindicated in pregnancy.

The sexual partner must be treated, and a test-of-cure culture should be obtained after treatment.

ComplicationsRisk Assessment

Risk assessment is one of the most important components of prenatal care. It is a continuous exercise that must take into account all aspects of the patient's medical, social, and economic status. Designation of a pregnancy as low risk or high risk creates specific expectations and requirements for prenatal management.

Low risk implies expectation of a favorable outcome, placing more prenatal care focus on health maintenance and social issues than on specific medical management.

High risk implies a need for increased surveillance, special care, and appropriate referrals. Categories of increased risk that should be identified and given appropriate attention include

o Pre-existing medical illness

o Previous pregnancy complications, such as perinatal mortality, prematurity, fetal growth retardation, malformations, placental accidents, and maternal hemorrhage

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o Evidence of poor maternal nutritiono Onset of complicating events that may transform a low-risk pregnancy into a

high-risk pregnancy.

Genetics Referral Congenital anomalies and diseases are a major cause of infant morbidity and mortality. Indications for genetic referral include

o Maternal age >35 years at the time of the EDC

o Family history of congenital anomalies or inherited disorders

o Abnormal development or mental retardation of a previous child

o Ethnic background associated with inheritable diseases

o Substance use or exposure to teratogens

o Three or more consecutive spontaneous abortions.

Subsequent Prenatal CareRegular prenatal visits allow ongoing evaluation and assurance that the pregnancy is

progressing normally. For low-risk pregnancies, the recommended frequency of prenatal visits is monthly up to

32 weeks, every 2 weeks up to 36 weeks, and then weekly until delivery. Standard assessment at each prenatal visit includes maternal weight, blood pressure,

uterine size, auscultation of fetal heart tones, and evaluation for edema, proteinuria, and glucosuria. After 18 to 20 weeks, the patient should be questioned about fetal movements. Late in pregnancy, the presenting fetal part should be determined.

Ongoing patient education appropriate to the gestational age of the fetus is incorporated into these visits.

All prenatal care information should be recorded on a standardized form.

Guidelines for Patients Nutrition: A common-sense approach is necessary because there are many limitations to

our understanding of the nutritional needs of pregnancy.o Suggestions include eating foods from each of the major food groups, consuming

adequate liquids (especially water), adding fiber, and ensuring adequate calcium intake.

o For a woman whose weight is normal before pregnancy, normal pregnancy weight gain is 20 to 27 lb (10 to 12 kg). This is usually achieved by eating a well-balanced diet containing 60 to 80 g of protein, 2,400 or more calories, low sugars and fats, high fiber, and at least three glasses of milk or other dairy equivalents daily. An underweight woman is at an increased risk for a growth-retarded infant, and more weight gain is often required. Excessive weight gain or pre-existing maternal obesity (more than 200 lb or 90 kg) may, in some cases, be associated with increased risk of fetal macrosomia. This is a significant risk factor for the infant in terms of birth trauma and cesarean delivery.

o Routine prescription of prenatal vitamins is probably not necessary. Practically all diets that supply adequate caloric intake for appropriate weight gain will also provide enough minerals. There are two exceptions:

Folic acid supplementation preconceptually and throughout the early part of pregnancy has been shown to decrease the incidence of fetal neural tube defects.

Iron supplementation is recommended after 28 weeks' gestation because increased iron requirements in the latter part of pregnancy are difficult to meet via a normal diet.

Working during pregnancy: Most women can safely work until term without complications.

o A flexible approach must be taken because pregnant women may have less tolerance to heat, humidity, environmental pollutants, prolonged standing, and heavy lifting.

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o Pregnant women who should probably not work include those with a history of two premature deliveries, incompetent cervix, fetal loss secondary to uterine abnormalities, cardiac disease greater than class II, Marfan syndrome, hemoglobinopathies, diabetes with retinopathy or renal involvement, third-trimester bleeding, premature rupture of the membranes, or multiple gestation after 28 weeks.

Exercise: Women should be encouraged to exercise if they have no complicating factors.

o Exercise recommendations should be tailored according to the level of physical activity of the patient before she became pregnant and according to her level of physical fitness. A trained athlete can continue rigorous training during pregnancy but should avoid raising her core temperature or becoming dehydrated.

o Exercise should be varied during the third trimester to avoid too much stress on knee and ankle joints. Walking, swimming, and prenatal aerobic classes can be adapted to the needs of most women.

Smoking should be discontinued during pregnancy.

o It is important to counsel patients about antenatal smoking risks and cessation recommendations and to record their compliance.

o The potentially harmful effects of cigarette smoking during pregnancy include

Low birth weight

Premature labor

Spontaneous abortion

Stillbirth

Crib death

Birth defects

Increased respiratory problems in newborns.

o Smoking more than ten cigarettes a day can have a pronounced effect on birth weight.

o Patient education is important because many women do not understand the severity of the risks. A pregnant patient's desire to stop smoking should be supported by a nicotine withdrawal program or system and with counseling or referral to appropriate community groups.

Alcohol use should be discontinued in pregnancy, including social and binge drinking.

o There may be a linear relationship between alcohol consumption and fetal damage, which would explain why even limited fetal exposure to alcohol through social or binge drinking can be damaging.

o Fetal alcohol syndrome (FAS) is the result of chronic fetal alcohol exposure.

With chronic alcoholism, the risk of FAS is 20% to 40%.

Variants of FAS may also result from binge drinking or persistent social drinking.

FAS occurs as a characteristic pattern of physical abnormalities that includes intrauterine growth retardation and mental retardation. As such, it is an important cause of poor fetal growth and abnormal development.

FAS includes

Cardiac malformations

Central nervous system anomalies such as microcephaly and neural tube defects

Micrognathia, cleft lip/cleft palate and other facial abnormalities

Skeletal and truncal abnormalities including diaphragmatic hernia

Genitourinary malformations.

Seat belt use is the same as for the nonpregnant automobile passenger: The lap belt is worn low and snugly across the hip bones; the shoulder harness is worn over one shoulder and under the opposite arm, loosely enough to place a clenched fist between the sternum and the belt.

Sexual relations: There are no restrictions for the patient without complications. Whatever is comfortable and pleasurable may be continued unless and until a pregnancy complication occurs (e.g., undiagnosed bleeding, preterm labor, placenta previa,

P.12rupture of the membranes). Patients should be warned specifically against the forcing of air into the vagina during orogenital sex because of reports of sudden maternal death or stroke.

Fetal movement is generally discernible by the mother at 18 to 20 weeks' gestation.o Fetal activity is cyclic in nature and will normally vary in frequency and intensity

throughout the day.

o Presence of fetal movement is considered reassuring to the mother.

o Lack of fetal movement or a marked decrease in frequency is often worrisome to the mother but is not a specific marker of fetal compromise. Most typically, this occurs in conjunction with fetal sleep cycles.

o Prolonged absence of fetal movement is best evaluated by a nonstress test with ultrasound biophysical profile as backup assessment.

Warning signs of preterm labor.

o Studies have suggested that patient education regarding the warning signs for preterm labor leads to improved rates of early diagnosis of preterm labor. Self-identification allows these patients to seek the attention of the health care staff earlier in their preterm delivery course.

o Creasy et al. (1) noted the following warning signs:

A feeling that the baby is “balling up†that lasts more than 30 seconds� and occurs more than four times per hour

Contractions or intermittent pains or sensations between nipples and knees lasting more than 30 seconds and recurring four or more times per hour

Menstrual-like sensations, occurring intermittently

Change in vaginal discharge, including bleeding

Indigestion or diarrhea

Common complaints are a significant part of pregnancy. After investigating to rule out a serious pathologic condition, treatment may be directed to symptomatic relief.

o Headache and backache. Acetaminophen (Tylenol), 325 to 650 mg every 3 to 4 hours, is usually sufficient. Mild narcotics such as codeine should be reserved for refractory severe headaches or migraines. Aspirin should be avoided during pregnancy (2).

o Nausea and vomiting:

First-trimester morning sickness may be treated symptomatically and relieved by eating frequent, small meals and avoiding spicy or greasy foods.

Severe, persistent, symptoms may require hospitalization and intravenous fluids. The antiemetics, promethazine (Phenergan), diphenhydramine (Benadryl), and several other antihistamines (2) are considered safe for use in pregnancy and have no known association with birth defects.

Bendectin, the traditional antinausea medication for pregnancy, has been removed from the market by the manufacturer, but an equivalent substitute is available through the use of pyridoxine (vitamin B6) and Unisom.

o Constipation:

A high-fiber diet, increased fluid intake, and regular exercise are recommended. Stool softeners such as docusate sodium (Colace) or psyllium hydrophilic mucilloid (Metamucil) may help.

Mild laxatives should be used sparingly and only if the prior measures fail.

o Varicosities: Support stockings and leg elevation are recommended.

o Other important information for patients to know:

When and where to call if they have questions or problems

Availability of childbirth classes

Signs of the onset of labor

Obstetric analgesic options

Indications for cesarean delivery

Home safety

Infant care and feeding, including breast-feeding

Access to consumer education (e.g., infant safety products, furniture, car seats)

Birth control counseling.

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Patient Education Effective prenatal care requires patient education. One of the primary goals of prenatal care is to encourage patient responsibility through

active participation in their prenatal care plan.

In order for women to make effective choices, they need information about pregnancy and prenatal care before becoming pregnant.

Women desire more control of the birthing process. To achieve this control, they need specific information and interactive discussion with their health care providers.

Each woman's personal socioeconomic situation and support system must be explored and taken into account as part of her prenatal plan of care.

References1. Creasy RK, Gummer BA, Liggins GC. System for predicting spontaneous preterm birth. Obstet Gynecol 1980;55:692–695.2. Briggs GG, Freeman RK, et al. Drugs in pregnancy and lactation. 7th ed. Philadelphia: Lippincott Williams & Wilkins; 2005.Selected ReadingsGilstrap LC, Oh W, eds. Guidelines for perinatal care. 5th ed. Chicago: American Academy of Pediatrics and the American College of Obstetricians and Gynecologists; 2002.Cummingham FG, Gant NF, Leveno KJ, et al., eds. Williams obstetrics. 21st ed. New York: McGraw-Hill; 2001.Cefalo RC, Moos MK, eds. Preconceptional health care, a practical guide. 2nd ed. St. Louis: Mosby; 1995.