Learning Objectives
The student should be able to:
Describe the essential features of a preconception consultation, including how to incorporate this content into any visit.
Discuss chlamydia screening.
Demonstrate the use of the HEEADSS adolescent-interviewing technique.
Recognize pregnancy: intrauterine, ectopic, and miscarriage.
Discuss options during an unplanned pregnancy.
Select initial prenatal labs.
Counsel a pregnant patient for healthy behavior, folic acid supplementation, and immunizations.
Outline normal progression of symptoms and physical exam findings during pregnancy.
Demonstrate the management of a miscarriage, including the medical and social follow-up.
Knowledge
Chlamydia: Epidemiology, Course of Disease, and Screening Recommendations
Epidemiology
Chlamydial infection is the most common sexually transmitted bacterial infection in the United States. In 2007, more than 1.1 million chlamydia cases were reported to the CDC. It is thought that another million cases of chlamydia remain unreported.
Course of disease
Chlamydia is often insidious and asymptomatic. In women, genital chlamydial infection may result in urethritis, cervicitis, pelvic inflammatory disease (PID), infertility, ectopic pregnancy, and chronic pelvic pain. Chlamydial infection during pregnancy is related to adverse pregnancy outcomes, including miscarriage, premature rupture of membranes, preterm labor, low birth weight, and infant mortality.
Screening recommendations
The USPSTF found fair evidence that nucleic acid amplification tests (NAATs) can identify chlamydial infection in asymptomatic men and women, including asymptomatic pregnant women, with high test specificity. In low prevalence populations, however, a positive test is more likely to be a false positive than a true positive, even with the most accurate tests available.
Qualities of a Good Screening Test
1. The condition should be an important health problem and the condition screened for must have a high prevalence in the population.
2. There should be a latent stage of the disease.
3. There should also be effective treatment for the condition being screened.
4. Facilities for diagnosis and treatment should be available.
5. There should be a test or examination for the condition.
6. The test should be acceptable to the population and the total cost of finding a case should be economically balanced in relation to medical expenditure as a whole. The potential benefits of early detection and treatment of a condition need to be weighed against many factors, including adverse side effects of the screening test, time and effort required (of both the patient and the health care system) to take the test, financial cost of the test, potential psychological and physical harm of false positive results (such as labeling and overtreatment), and adverse effects of the treatment.
7. The natural history of the disease should be adequately understood.
8. There should be an agreed policy on whom to treat.
9. Case-finding should be a continuous process, not just a “once and for all” project.
10. An effective screening test should have very good sensitivity (identify most or all potential cases) and specificity (label incorrectly as few as possible as potential cases). Even a test with a sensitivity of 95% will lead to many false positives when the prevalence of the condition is very low.
United States Preventive Services Task Force Recommendations for Chlamydia Screening
The USPSTF
recommends screening for chlamydia infection in the following:
Grade
Recommendation
Rationale:
All sexually active
women age 24 and younger
Sexually active women age 25 and older who are at increased risk
Grade B recommendation
There is direct evidence that screening reduces complications of chlamydial infection in women who are at increased risk, with a moderate magnitude of benefit. Such complications include pelvic inflammatory disease, infertility, and premature delivery (among pregnant women).
The USPSTF advises against screening women age 25 and older if not at increased risk, regardless of pregnancy status. Only the above categories are found to have a high enough pretest probability to recommend screening. Women (pregnant or non-pregnant) in general are not recommended for chlamydial screening as the overall benefit of screening would be small, given the low prevalence of infection among women not at increased risk.
Risk factors for chlamydial infection include a history of chlamydial or other sexually transmitted infection, new or multiple sexual partners, inconsistent condom use, and exchanging sex for money or drugs. Risk factors for pregnant women are the same as for nonpregnant women.
The USPSTF states that there is “Insufficient” evidence for or against screening men.
The CDC recommends consideration of screening for chlamydia in sexually active young men in settings with high prevalence or in men with high risk behaviors overall.
1. The CDC recommends consideration of screening for chlamydia in sexually active young men in settings with high prevalence or in men with high-risk behaviors overall.