What is the procedure for performing a pap (Papanicolaou) smear on a female patient between 21 and 65 years old?

How to Perform a Pap Smear

Cervical sampling is performed by gently scraping the ectocervix with a curved spatula in a circular fashion, followed by insertion and rotation of an endocervical brush to obtain the endocervical sample. 1

Equipment Selection

• Use either a wooden or plastic spatula for the ectocervical sample 1
• An endocervical brush (cytobrush) must be used in addition to the spatula to adequately sample the transformation zone 1
• Alternative: The Papette brush can be used as a single collection device and is non-inferior to the traditional spatula-cytobrush combination (93.8% vs 93.0% satisfactory results) 2

Step-by-Step Technique

Ectocervical Sampling

• Insert the speculum to visualize the cervix 1
• Place the curved spatula against the cervix with the longer projection fitting into the cervical os 1
• Rotate the spatula 360 degrees in a circular fashion while maintaining gentle contact with the cervical surface 1
• This scraping motion should be gentle but firm enough to collect adequate cellular material 1

Endocervical Sampling

• Insert the endocervical brush into the cervical os 1
• Gently rotate the brush 90-180 degrees (one-quarter to one-half turn) 1
• Avoid excessive rotation or force, which can cause bleeding and obscure the sample 1

Specimen Handling

• Perform fixation promptly after collection to prevent air-drying artifact 1
• For liquid-based cytology: Rinse the spatula and brush in the collection vial according to manufacturer instructions 1
• For conventional Pap smears: Spread the sample thinly and evenly on a glass slide and immediately apply fixative 1

Special Considerations for Challenging Cases

Postmenopausal/Atrophic Cervix

• The postmenopausal woman may have an atrophic vagina, stenotic cervical os, and inaccessible squamocolumnar junction 1
• Use a smaller speculum if the vaginal canal is narrowed 1
• Gentle technique is essential to avoid trauma and bleeding 1
• When the vagina is too small for speculum insertion and the cervix cannot be palpated, blind swabbing or vaginal aspiration has been suggested but is of unproven value 1

Technical Quality Considerations

• Both ectocervical and endocervical components must be present for the specimen to be considered satisfactory 1
• The entire transformation zone (squamocolumnar junction) should be sampled, as this is where most cervical neoplasia originates 1
• Liquid-based cytology has advantages over conventional Pap smears: allows for reflex HPV testing from the same sample and is easier to read 1
• Most cervical cytology testing in the United States is now performed with liquid-based cytology 1

Common Pitfalls to Avoid

• Inadequate endocervical sampling is a frequent cause of unsatisfactory specimens—always use the endocervical brush 1
• Delayed fixation causes air-drying artifact that makes interpretation difficult 1
• Excessive bleeding from traumatic technique can obscure cellular detail 1
• Sampling only the ectocervix without the endocervical component misses the transformation zone where most lesions develop 1

When to Perform the Test

• Screen women aged 21-65 years regardless of sexual activity history 1, 3
• Do not screen women under age 21 even if sexually active, due to very low cancer risk and high rates of spontaneous clearance 1, 4
• Screening intervals: Every 3 years for ages 21-29 with cytology alone; every 5 years for ages 30-65 with HPV cotesting (preferred) or every 3 years with cytology alone 1, 3