Pregnancy

Key Features

Essentials of Diagnosis

• Amenorrhea, weight gain, nausea and vomiting, and breast changes

• Positive pregnancy test

General Considerations

• Prompt diagnosis of pregnancy allows early prenatal care and avoidance of harmful activities or exposures

• In the event of an unwanted pregnancy, early diagnosis allows for counseling regarding adoption or termination

Clinical Findings

Symptoms and Signs

• Amenorrhea, weight gain

• Nausea and vomiting

• Breast tenderness and tingling

• Urinary frequency and urgency

• "Quickening" (perception of the first fetal movement) is noted at about 18 weeks' gestation

• Signs

  • Breast changes, abdominal enlargement, and cyanosis of the vagina and cervical portio (week 7)

  • Softening of the cervix (week 7)

  • Generalized enlargement and softening of the corpus (post-week 8)

  • Uterine fundus is palpable above the pubic symphysis by 12–15 weeks from last menstrual period

  • Fundus reaches the umbilicus by 20–22 weeks

  • Fetal heart tones heard by Doppler at 10–12 weeks

Differential Diagnosis

• Myomas can be confused with a gravid uterus

• A midline ovarian tumor may displace a nonpregnant uterus

• Ectopic pregnancies may show lower levels of human chorionic gonadotropin (hCG) that level off or fall

• Premature menopause

Diagnosis

Laboratory Tests

DIAGNOSTIC TESTS

• All urine or blood pregnancy tests rely on detection of placental hCG and are accurate at the time of a missed period or shortly after it

• Laboratory and home assays use monoclonal antibodies specific for hCG

• hCG levels increase shortly after implantation, double every 48 hours (this rise can range from 30% to 100% in normal pregnancies), peak at 50–75 days, and fall in second and third trimesters

SCREENING AT THE TIME OF DIAGNOSIS

• The following are recommended

  • Urinalysis; culture of a mid-stream urine sample

  • Complete blood count (CBC)

  • Random blood glucose

  • Serologic test for syphilis

  • Rubella antibody titer

  • History of varicella

  • Blood group and Rh type

  • Antibody screening

  • Hepatitis B surface antigen testing

• HIV testing should be encouraged

• Cervical cultures for Neisseria gonorrhoeae and Chlamydia trachomatis as well as Papanicolaou smear are indicated

• Testing for abnormal hemoglobins should be done in patients at risk for sickle cell or thalassemia traits

• Tuberculosis skin testing is recommended for high-risk groups

• Screening for Tay-Sachs, Canavan disease, and familial dysautonomia should be offered to

  • Jewish women with Jewish partners (especially those of Ashkenazi descent)

  • Couples of French-Canadian or Cajun ancestry

• Hepatitis C screening should be offered to mothers at high risk

SCREENING DURING PREGNANCY

• In the first ...