How should a comprehensive obstetric examination be performed?

How to Perform an Obstetric Examination

An evidence-based obstetric examination for asymptomatic pregnant patients should include: inspection and palpation for thyromegaly and cervical lymphadenopathy, cardiac auscultation, fundal height measurement starting at 20 weeks, and selective pelvic examinations for specific indications only—not as routine screening 1.

Essential Components by Trimester

First Trimester (Up to 13 weeks)

• Vital signs: Blood pressure, weight, BMI calculation 2
• Thyroid examination: Inspect and palpate for thyromegaly 1
• Cardiac auscultation: Listen for murmurs or abnormal heart sounds 1
• Pelvic examination: Only if indicated for:
  • Testing for gonorrhea and chlamydia 1
  • Evaluating abnormal bleeding or pain 3
  • Suspected ectopic pregnancy 4

Key caveat: Routine pelvic examination in asymptomatic women lacks evidence for benefit and may cause unnecessary anxiety, pain, and discomfort 5, 6. The American College of Physicians found inadequate evidence supporting screening pelvic examinations for detection of gynecologic conditions 5.

Second Trimester (14-27 weeks)

• Fundal height measurement: Begin at 20 weeks, measure from pubic symphysis to uterine fundus in centimeters 1

  • Expected measurement approximates gestational age in weeks (±2-3 cm)
  • Discrepancies warrant ultrasound evaluation for growth abnormalities

• Abdominal palpation: Assess uterine size, fetal position (after 24 weeks), and maternal-fetal bonding 7

  • This provides sensory aspects not obtained from ultrasound
  • Facilitates maternal-fetal attachment through touch 7

• Cervical examination: Not routinely indicated unless:

  • Symptoms of preterm labor
  • Ultrasound-detected cervical shortening 1
  • Vaginal bleeding or discharge requiring evaluation

Third Trimester (28 weeks to delivery)

• Fundal height measurement: Continue at each visit 1

  • Declining or static measurements suggest growth restriction
  • Excessive measurements suggest macrosomia, polyhydramnios, or multiple gestation

• Leopold maneuvers (after 32 weeks): Systematic four-step abdominal palpation to determine:

  1. First maneuver: Fundal palpation—identify fetal pole (head vs. breech)
  2. Second maneuver: Lateral palpation—locate fetal back and small parts
  3. Third maneuver: Suprapubic palpation—identify presenting part
  4. Fourth maneuver: Pelvic inlet palpation—assess engagement of presenting part

• Pelvic examination indications:

  • Assessment of cervical dilation and effacement after 37 weeks 8
  • Evaluation of pelvimetry if vaginal delivery concerns exist 1
  • Suspected rupture of membranes or preterm labor
  • Placental location assessment if placenta previa suspected (use ultrasound first) 9

Specific Clinical Scenarios Requiring Examination

Acute Pelvic Pain with Positive Pregnancy Test

• Transvaginal ultrasound is primary modality, not pelvic examination 4
• Pelvic examination only if ultrasound unavailable or to assess cervical os status
• Doppler imaging integral for evaluating ectopic pregnancy 4

Multiple Gestations

• Abdominal examination with fundal height less reliable 9
• Ultrasound surveillance every 3-4 weeks for dichorionic twins 9
• Document placental cord insertion sites in second trimester 9

Post-Bariatric Surgery Pregnancy

• Monthly weight measurement to assess gestational weight gain 10
• Monthly fetal growth ultrasound from viability 10
• Standard abdominal examination with attention to excessive or inadequate weight gain

What NOT to Do

Avoid routine screening pelvic examinations in asymptomatic pregnant women 5, 6, 1. The evidence shows:

• No mortality or morbidity benefit for screening pelvic examination 5
• False-positive rates for ovarian pathology: 1.2-8.6% 5
• Causes anxiety, pain, discomfort in one-third of women 6
• May serve as barrier to accessing contraception and preventive care 6

Do not perform speculum examination before prescribing hormonal contraception 3. Package inserts for oral contraceptives specifically state gynecologic examination is unnecessary 3.

Critical Examination Principles

1. Prepare the patient: Explain each step before performing it, especially for abdominal palpation 7
2. Involve the patient: Allow her to feel fetal parts during Leopold maneuvers to enhance bonding 7
3. Use appropriate draping: Maintain dignity while allowing adequate exposure for examination
4. Document findings: Record fundal height measurements, fetal position, estimated fetal weight, and any abnormalities
5. Integrate ultrasound appropriately: Use point-of-care ultrasound when available for fetal heart rate, presentation, and amniotic fluid assessment 11, 12

The modern obstetric examination prioritizes evidence-based maneuvers that provide clinical value while minimizing unnecessary invasive procedures that lack proven benefit and may cause patient harm 1.