STI Screening in Pregnancy

Why screening for STI important in pregnany and how is it done?

Pregnant women are considered a ‘special population’ by the CDC. Due to the potential burden to pregnant women, offspring and partners, providers should ask all pregnant women and their partners about STIs, and ensure counseling, screening and treatment are available.

Recommended Screening Tests for ALL Pregnant Women

HIV

‘Opt-out screening’ – screen at first prenatal visit after notifying patient of the need to be screened, unless patient declines

• Screen in prepregnancy or as early as possible in pregnancy

If patient declines, address concerns and discuss the following 

• A previous negative HIV test does not mean patient is still negative
• Health benefit not only to patient but to fetus/offspring as treatment available to reduce perinatal transmission

Test again in 3rd trimester (before 36 weeks, if possible) if at high riskIllicit drug use

• STI during pregnancy
• 
  
• Multiple sex partners during pregnancy
• 
  
• Live in areas of high HIV incidence
• 
  
• Receiving care in facilities with an HIV incidence in pregnant women ≥1/1,000 per year
• Partner has HIV
• Signs or symptoms of acute HIV infection :

1. Fever 
2. Lymphadenopathy
3. Skin rash
4.  Myalgias
5.  Arthralgias 
6. Headache 
7. Oral Ulcers 
8.  Leukopenia 
9.  Thrombocytopenia 
10.  Elevated transaminase

Rapid HIV testing should be performed on any woman in labor who has not been screened during pregnancy, unless she declines

• If rapid HIV test positive, antiretroviral prophylaxis should be administered prior to receiving confirmatory test results
• AAP recommends expedited HIV testing as soon as possible after birth for infants born to women with unknown HIV status

NOTE: 

The USPSTF (June 2019) continues to recommend screening for HIV infection in all pregnant persons, including those who present in labor or at delivery whose HIV status is unknown. (A recommendation)

SYPHILIS

Serologic tests should be performed at first prenatal visit

Screening for syphilis infection is a 2-step process | Antepartum screening can be performed by manual nontreponemal antibody testing (e.g., RPR) by using the traditional syphilis screening algorithm or by treponemal antibody testing (e.g., immunoassays)

• Traditional screening: Initial “nontreponemal” antibody test (ie, Venereal Disease Research Laboratory test or rapid plasma reagin [RPR] test) to detect biomarkers released from damage caused by syphilis infection, followed by a confirmatory “treponemal” antibody detection test (ie, fluorescent treponemal antibody absorption [FTA-ABS] or T pallidum particle agglutination test [TP-PA])
• Reverse sequence screening algorithm: Automated treponemal test (such as an enzyme-linked [EIA], chemiluminescence [CIA], or multiplex flow immunoassay [immunoblot]) performed first, followed by a nontreponemal testIf the test results of the reverse sequence algorithm are discordant, a second treponemal test (preferably using a different treponemal antibody) is performed
• Pregnant women with positive treponemal screening tests (e.g., EIA, CIA, or immunoblot) should have additional quantitative nontreponemal testing because titers are essential for monitoring treatment response

If access to prenatal care is suboptimal, RPR test and treatment should be performed at time of pregnancy confirmation

Serologic retesting in the 3rd trimester (28 weeks) and at delivery if the patient for patients at high risk including

• Sex with multiple partners | Sex in conjunction with drug use or transactional sex
• Late entry to prenatal care (i.e., first visit during the second trimester or later) or no prenatal care
• Methamphetamine or heroin use
• Incarceration of the woman or her partner
• Unstable housing or homelessness

Test any woman who delivers a stillborn or in the case of infant death

• Untreated syphilis has a 40% infant death rate

Do NOT discharge neonate if serologic status is unknown

• Newborn infection may not be immediately obvious
• Within a few weeks may develop

1. Developmental delay
2. Seizures
3. Birth defects such as bone deformation, blindness and deafness

Note: In September 2018, the USPSTF reaffirmed previous guidance and “recommends early screening for syphilis infection in all pregnant women.” (Grade A – Offer or Provide this Service)

HEPATITIS B (HBV)

Test for hepatitis B surface antigen (HBsAg) at the first prenatal visit regardless of previous testing or vaccination

At time of admission for delivery, retest if patient:

• Is at high risk – more than one sex partner in previous 6 months, evaluation or treatment for STI, injection-drug use, HBsAG-positive sex partner
• Was not screened prenatally
• Has clinical hepatitis

Always do HBsAg testing prior to giving the HBV vaccine to avoid misinterpretation

Report HBsAg positive women to local or state health departments to ensure they are entered into a case management program to arrange access to appropriate vaccinations for contacts and prophylaxis for infants

• If HBsAg positive, test for hepatitis B virus deoxyribonucleic acid (HBV DNA) to guide the use of antiviral medication to prevent perinatal transmission
• If HBV DNA >200,000 IU/mL (7.6 log10 IU/mL): The American Association for the Study of Liver Diseases suggests antiviral therapy during pregnancy to further reduce perinatal HBV transmission

Recommended Screening Tests for Pregnant Women at Risk

CHLAMYDIA 

Test all pregnant women who are <25 years old for Chlamydia trachomatis at the first prenatal visit

Test all older women if at high risk:

• More than one sex partner
• A sex partner with concurrent partners or has an STI

Retest in 3rd trimester to prevent maternal postnatal complications and chlamydia infection in the neonate

Test of cure by NAAT 3 to 4 weeks after treatment and retest within 3 months

GONORRHEA 

Test all pregnant women who are <25 years old for N. gonorrhoeae at the first prenatal visit

Test all older women if at high risk:

• More than one sex partner
• A sex partner with concurrent partners or has an STI
• Inconsistent condom use in non-monogamous relationships
• Previous or co-existing sexually transmitted infections
• Exchanging sex for money or drugs
• Consider consulting local public health authorities for further guidance on identifying those at high risk related to geographic location

Treat all positive patients immediately and retest in 3 months

Retest in the 3rd trimester to prevent maternal postnatal complications and chlamydia infection in the neonate

HEPATITIS C 

(HCV) The CDC has updated HepC guidelines (2020)

• Hepatitis C screening at least once in a lifetime for all adults aged ≥18 years, except in settings where the prevalence of HCV infection (HCV RNA-positivity) is <0.1%
• Hepatitis C screening for all pregnant women during each pregnancy, except in settings where the prevalence of HCV infection (HCV RNA-positivity) is <0.1%

USPSTF also calls for universal screening for HCV infection, including pregnancy

Screen Only if Symptomatic

Bacterial Vaginosis (BV)

• Evidence does not support routine screening
• Evaluate and screen symptomatic women

Trichomonas

• Evidence does not support routine screening
• Evaluate and screen symptomatic women

HSV-2

• Evidence does not support routine screening
• In the absence of lesions during the 3rd trimester, routine cultures for HSV are not indicated for women in the 3rd trimester who have a history of recurrent genital herpes
• Type-specific serologic tests may help identify pregnant women at risk for HSV and to help guide counseling regarding the risk of acquiring herpes during pregnancy

Summary

Recommendations for STI testing can vary based on certain considerations, including state laws. The CDC recommendations are considered broader, such that more women will potentially be screened, but are consistent with other CDC guidance with the intention of preventing adverse outcomes for pregnant women, partners and fetuses.

KEY POINTS:

All pregnant women and their partners should be asked about STIs and counseled regarding personal risks as well as pregnancy and outcomes

Pap Smears should be performed in pregnancy at the same frequency as nonpregnant women

• Management of abnormal Pap tests differ in pregnancy

Screening at Delivery

SYPHILIS 

• Select groups of pregnant women, including women who are at high risk for syphilis or live in areas of high syphilis morbidity
• Pregnant women with no previously established status
• Pregnant women who deliver a stillborn infant

HIV

Pregnant women not screened during pregnancy

HBV

Women admitted for delivery at a health care facility without documentation of HBsAg test results should have blood drawn and tested as soon as possible after admission

Women at high risk

• Having had more than one sex partner during the previous 6 months, an HBsAg-positive sex partner, evaluation or treatment for a sexually transmitted disease, or recent or current injection-drug use

Women with signs or symptoms of hepatitis

Note: CDC recommends universal hepatitis B vaccination within 24 hours of birth for medically stable infants >2000 grams

Permissive language that allowed the vaccine to be delayed until after hospital discharge has been removed

Administer hepatitis B vaccination and hepatitis immune globulin regardless of birth weight within 12 hours of birth for infants born to hepatitis b-infected mothers

CHLAMYDIA

Pregnant women less than 25 years of age

Continued high risk

• New or multiple sex partners, sex partner with concurrent partners, sex partners who have a sexually transmitted disease

GONORRHEA 

Continued high risk

• Past or current injection-drug use, having had a blood transfusion before July 1992, receipt of an unregulated tattoo, having been on long-term hemodialysis, intranasal drug use, and other percutaneous exposures

Jose Phiri