Public Health and Prevention in Preconception Care: Infectious Diseases and Immunization

Guidance for Health Care Providers

Preconception Care as Public Health Prevention

Preconception care is an important opportunity to implement preventive health strategies that improve maternal and infant outcomes.

Many infectious risks affecting pregnancy—including vaccine-preventable diseases, sexually transmitted infections, chronic viral infections, and environmental exposures—can be identified and addressed before pregnancy occurs.

Routine clinical encounters with individuals of reproductive age provide opportunities to:

  • Review vaccination status
  • Screen for sexually transmitted infections
  • Identify and manage chronic infections
  • Provide counselling about infectious exposures and travel risks

Integrating these preventive measures into routine care helps reduce maternal morbidity, prevent congenital infections, and support healthier pregnancies. For more information, refer to SOGC Guideline No. 357-Immunization in Pregnancy.

Key Messages for Providers

Preconception care allows clinicians to apply public health prevention strategies before pregnancy begins.

Key components include:

  • Vaccination and immunity review
  • Screening for sexually transmitted infections
  • Management of chronic infectious diseases
  • Counselling about environmental and travel-related infection risks

Preventive interventions delivered before conception can significantly reduce the risk of infection-related pregnancy complications.

Why Public Health Prevention Matters

Many infections that affect pregnancy outcomes are preventable through vaccination, screening, early treatment, or behavioural interventions. Identifying infectious risks before pregnancy allows clinicians to implement preventive strategies that reduce maternal illness and prevent congenital infection.

Preconception care, therefore, represents an important public health intervention, helping to improve reproductive health outcomes at both the individual and population level.

Preconception care allows providers to:

  • Identify infections before pregnancy
  • Treat or stabilize chronic infectious conditions
  • Prevent congenital infections
  • Reduce maternal complications

Early preventive care improves both maternal and neonatal health outcomes.

Clinical Pearl: Preventive interventions before pregnancy are more effective than treatment during pregnancy.

Screening, vaccination, and early treatment can significantly reduce infection-related complications.

Core Clinical Principles

Preconception infectious disease prevention focuses on identifying and addressing modifiable risks before pregnancy occurs.

Providers should emphasize:

  • Vaccination and immunity review
  • Routine screening for sexually transmitted infections
  • Early identification of chronic infectious diseases
  • Counselling about environmental and travel-related exposures
  • Multidisciplinary care when complex infections are identified

Preventive strategies integrated into routine care improve maternal and infant health outcomes.

Routine Screening and Risk Assessment

Assessing infectious disease risks should be part of routine care for individuals of reproductive age.

Screening allows clinicians to identify infections that may affect fertility, pregnancy outcomes, or neonatal health, many of which are asymptomatic.

Preconception screening should include assessment of:

  • Vaccination history
  • Sexual health and risk of sexually transmitted infections
  • Chronic infections
  • Environmental exposures
  • Travel history

Routine, non-judgmental screening helps ensure early identification and management of infectious risks.

Why Infectious Disease Prevention Matters in Preconception Care

Many infections that affect pregnancy outcomes can be prevented through vaccination, screening, early treatment, and behavioural interventions. Addressing infectious disease risks before pregnancy allows clinicians to reduce maternal illness, prevent congenital infections, and improve neonatal outcomes. Integrating infectious disease prevention into routine care for individuals of reproductive age represents an important opportunity to improve reproductive health at both the individual and population level.

Immunization and Prevention

Vaccination is one of the most effective strategies for preventing infectious diseases that can affect pregnancy and neonatal health. Preconception care provides an opportunity to review immunization status and ensure immunity to key vaccine-preventable infections before pregnancy occurs. For more information, refer to the SOGC Guideline No. 357-Immunization in Pregnancy.

Key Preconception Actions

  • Confirm immunity to rubella and varicella before pregnancy
  • Assess measles immunity if vaccination history is uncertain
  • Administer live attenuated vaccines at least 4 weeks before conception if immunity is absent
  • Review hepatitis B immunity in at-risk populations
  • Provide counselling regarding vaccines recommended during pregnancy (e.g., Tdap, influenza, COVID-19)

Live vaccines are contraindicated during pregnancy, making preconception immunization particularly important.

Screening and Prevention of Sexually Transmitted Infections

Sexually transmitted infections (STIs) are common and frequently asymptomatic. Untreated infections can lead to infertility, pregnancy complications, and neonatal infection.

Preconception care provides an opportunity to identify and treat infections before pregnancy, reducing both maternal complications and the risk of vertical transmission.

Routine screening helps identify asymptomatic infections and reduce transmission. Early identification and treatment reduce complications such as pelvic inflammatory disease, infertility and congenital infection.

Chlamydia

Chlamydia trachomatis is the most commonly reported bacterial STI in Canada and often occurs without symptoms. Untreated infection can lead to pelvic inflammatory disease (PID), tubal infertility, ectopic pregnancy, and chronic pelvic pain. During pregnancy, chlamydial infection increases the risk of preterm birth and neonatal complications such as conjunctivitis and pneumonia.

Preconception clinical considerations

  • Screen sexually active individuals under 30 or those with risk factors
  • Use nucleic acid amplification testing (NAAT) from urine or vaginal swabs
  • Treat promptly with recommended antibiotics
  • Ensure partner notification and treatment

Early treatment helps prevent infertility and reduces the risk of neonatal infection.

Gonorrhea

Neisseria gonorrhoeae infection can lead to pelvic inflammatory disease, infertility, and chronic pelvic pain. In pregnancy, untreated infection increases the risk of miscarriage, preterm birth, and neonatal ophthalmia.

Preconception clinical considerations

  • Screen individuals at increased risk
  • Use NAAT testing
  • Treat with guideline-recommended dual therapy when indicated
  • Encourage partner testing and treatment

Rising antimicrobial resistance makes early identification and treatment particularly important.

Syphilis

Syphilis infection during pregnancy can result in severe fetal outcomes, including pregnancy loss, stillbirth, and congenital syphilis. Rates of syphilis have increased significantly in recent years in Canada and internationally. For more information, refer to the SOGC Infectious Disease Committee Statement on Syphilis

Preconception clinical considerations

  • Screen individuals with risk factors or high-prevalence settings
  • Use serologic testing
  • Treat early infection with penicillin therapy
  • Conduct partner notification

Early treatment prior to pregnancy virtually eliminates the risk of congenital syphilis.

Chronic Infectious Diseases

Individuals living with chronic infections benefit from early counselling and disease optimization prior to pregnancy. Preconception care allows time to stabilize disease, review medications, and reduce the risk of vertical transmission.For additional information, see SOGC Guideline No. 409: Intrauterine Fetal Diagnostic Testing in Women with Chronic Viral Infections.

HIV

Advances in antiretroviral therapy have dramatically improved pregnancy outcomes for individuals living with HIV. With appropriate treatment and viral suppression, the risk of vertical transmission can be reduced to less than 1%. For more information, refer to the SOGC Guideline No354 - Canadian HIV Pregnancy Planning Guidelines.

Key preconception priorities:

  • Achieve and maintain viral suppression
  • Review antiretroviral therapy for pregnancy safety
  • Screen and treat co-infections (e.g., hepatitis, sexually transmitted infections)
  • Provide counselling on transmission prevention

Care should be coordinated with infectious disease specialists and maternal-fetal medicine. With effective treatment, the vertical transmission risk is less than 1%.

Hepatitis B

Hepatitis B infection can be transmitted from parent to infant during childbirth. Without prevention, transmission risk may be as high as 90% in individuals with high viral load. SOGC Guideline No. 342-Hepatitis B and Pregnancy provides more detailed information.

Preconception clinical considerations

  • Screen individuals with risk factors or from endemic regions
  • Assess liver function and viral load
  • Review antiviral therapy
  • Vaccinate non-immune partners

Appropriate maternal management and neonatal immunoprophylaxis greatly reduce transmission risk.

Hepatitis C

Hepatitis C is increasingly recognized among individuals of reproductive age. Direct-acting antiviral therapies now allow for curative treatment prior to pregnancy. Refer to SOGC Clinical Consensus Statement No. 458: Hepatitis C Virus inPregnancy for detailed information.

Direct-acting antivirals can cure hepatitis C and should be considered before pregnancy when feasible.

Preconception clinical considerations

  • Screen individuals with risk factors (e.g., injection drug use history)
  • Confirm active infection with HCV RNA testing
  • Offer curative antiviral treatment prior to pregnancy when feasible
  • Avoid teratogenic medications such as ribavirin

Treating infection prior to pregnancy eliminates the vertical transmission risk.

Chagas Disease

Chagas disease, caused by Trypanosoma cruzi, is endemic in Latin America but increasingly recognized globally due to migration.

Vertical transmission can occur in approximately 1–5% of pregnancies in infected individuals.

Screening should be considered for individuals born in or who have lived in endemic regions of Latin America.

Preconception clinical considerations

  • Screen individuals born in or who lived in endemic regions
  • Confirm infection with serologic testing
  • Offer treatment prior to pregnancy when possible
  • Arrange neonatal testing if maternal infection is present

Preconception treatment significantly reduces the risk of congenital infection.

Environmental and Exposure Risks

Some infections that affect pregnancy arise from environmental exposures that can be prevented through simple behavioural measures. Preconception counselling provides an opportunity to educate patients about these risks and strategies to reduce exposure.

Key preventive measures include:

  • Avoiding sharing utensils or saliva exposure with young children to reduce CMV risk
  • Avoiding raw or undercooked meat to prevent toxoplasmosis
  • Washing fruits and vegetables thoroughly
  • Wearing gloves when gardening
  • Avoiding contact with cat litter where possible
  • Practicing good hand hygiene

Preventive counselling should be incorporated into routine preconception care.

Cytomegalovirus (CMV)

CMV is a common viral infection and a leading cause of congenital infection. Many adults acquire CMV through contact with saliva or urine from young children.

Primary infection during pregnancy can lead to congenital CMV, which may cause hearing loss, developmental delay, and neurological impairment. SOGC Guideline No. 420: Cytomegalovirus Infection in Pregnancy provides additional information.

Prevention strategies

  • Wash hands after contact with young children
  • Avoid sharing utensils or drinks
  • Avoid contact with saliva

Routine screening is not recommended, making prevention education especially important.

Toxoplasmosis

Toxoplasma gondii infection can be transmitted through contaminated food, soil, or cat feces. Infection during pregnancy may result in congenital infection with neurologic and ocular complications (see SOGC Guideline No. 285-Toxoplasmosis in Pregnancy: Prevention, Screening, and Treatment).

Prevention strategies

  • Avoid undercooked meat
  • Wash fruits and vegetables thoroughly
  • Wear gloves when gardening
  • Avoid handling cat litter when possible

Routine screening is not recommended in most settings.

Global and Travel Health Risks

International travel can expose individuals to infectious diseases that may affect pregnancy outcomes. Preconception visits provide an opportunity to review travel plans and discuss potential risks. When possible, travel to high-risk areas should be avoided during pregnancy planning. 

Zika Virus

Zika virus infection during pregnancy is associated with severe fetal neurological abnormalities, including microcephaly and congenital Zika syndrome. The SOGC has FAQs on Zika Virus.

Preconception clinical considerations

  • Reviewing travel plans
  • Discussing mosquito-bite prevention
  • Advising delays in pregnancy following travel to high-risk regions

Because infection may be asymptomatic, travel history is important in risk assessment.

Tuberculosis

Tuberculosis remains common globally and may be encountered in individuals from endemic regions.

Active TB during pregnancy is associated with increased maternal morbidity and adverse pregnancy outcomes.

Preconception clinical considerations

  • Screen individuals from high-prevalence settings
  • Evaluate for latent TB infection
  • Consider treatment prior to pregnancy

Early detection prevents maternal complications and reduces transmission risk.

Referral Pathways

Some infectious conditions require specialized management before pregnancy.

Referral may be appropriate for:

  • HIV or chronic viral infections
  • Complex STI management
  • Hepatology care for viral hepatitis
  • Infectious disease consultation for complex cases

Multidisciplinary care may include:

  • Infectious disease specialists
  • Hepatology
  • Maternal-fetal medicine
  • Pharmacy support

Practical Clinical Actions

Public health prevention strategies can be incorporated into routine visits with patients of reproductive age.

At routine visits, consider:

  • Reviewing vaccination status
  • Screening for sexually transmitted infections
  • Assessing risk for chronic infections
  • Counselling about environmental exposures
  • Reviewing travel plans and infection risks
  • Coordinating specialist referral when appropriate

Early preventive care can significantly reduce infection-related pregnancy complications.

Who Should Be Screened for Infectious Diseases?

Incorporate routine, non-judgmental screening into care for all individuals of reproductive age.

Sexually Transmitted Infections (STIs)

  • Sexually active individuals under 30
  • New or multiple sexual partners
  • History of STIs
  • Inconsistent condom use
  • Individuals in high-prevalence communities

Chronic Infections

  • Individuals from regions with a higher prevalence of:
    • HIV
    • Hepatitis B or C
    • Tuberculosis
  • History of injection drug use
  • Prior blood product exposure or incarceration

Travel and Exposure Risks

  • Recent or planned travel to endemic regions (e.g., Zika, TB)
  • Exposure to infectious diseases through work or community

Other Risk Considerations

  • Previous pregnancy with congenital infection
  • Symptoms suggestive of infection
  • Limited prior access to screening or primary care

Clinical Tip: Use universal, trauma-informed screening rather than risk-based assumptions to improve equity, disclosure, and early intervention.

Resources for Health Care Providers

To support infectious disease prevention and immunization in preconception care, the following resources provide clinical guidance, education, and practical tools.

SOGC Resources

Infectious Disease Prevention in Preconception Care: Clinician Quick Reference Table
A quick table on infection risks, screening, vaccination, and prevention before pregnancy.

Preconception Vaccination Quick Reference Chart
A quick chart on vaccines to review, update, or time before and during pregnancy.

SOGC Clinical Guidance

No 357: Immunization in Pregnancy
A clinical practice guideline that outlines evidence-based recommendations on immunization before, during, and after pregnancy to support maternal and infant health.

No 450: Care of Pregnant Women Living with HIV and Interventions to Reduce Perinatal Transmission
A clinical practice guideline that outlines evidence-based recommendations for the care of pregnant women living with HIV and the prevention of perinatal HIV transmission.

No 285: Toxoplasmosis in Pregnancy: Prevention, Screening, and Treatment
A clinical practice guideline that outlines evidence-based recommendations for screening, counselling, and managing alcohol use before and during pregnancy.

No 420: Cytomegalovirus Infection in Pregnancy
A clinical practice guideline that outlines evidence-based recommendations for the prevention, diagnosis, and management of cytomegalovirus infection in pregnancy.

No 409: Intrauterine Fetal Diagnostic Testing in Women with Chronic Viral Infections
A clinical practice guideline that outlines evidence-based recommendations for intrauterine fetal diagnostic testing in women with chronic viral infections.

No 342-Hepatitis B and Pregnancy
A clinical practice guideline that outlines evidence-based recommendations for screening, monitoring, and managing hepatitis B infection in pregnancy.

No 354 Canadian HIV Pregnancy Planning Guidelines
A clinical practice guideline that outlines evidence-based recommendations on pregnancy planning and preconception care for women living with HIV.

Clinical Consensus Statement No 458: Hepatitis C Virus in Pregnancy
A clinical consensus document that outlines evidence-based recommendations for the prevention, screening, diagnosis, and management of toxoplasmosis in pregnancy.

Infectious Disease Committee Statement on Syphilis
A committee statement that highlights the rising rates of syphilis in Canada and emphasizes the importance of screening and treatment during pregnancy to help prevent congenital syphilis.

Position Statement COVID-19 Vaccination in Pregnancy
A statement that summarizes recommendations on COVID-19 vaccination in pregnancy and supports informed decision-making to protect maternal and infant health.

Position Statement: The Prevention and Management of Oropouche Viral Disease in Pregnancy
A position statement that outlines recommendations for the prevention and management of Oropouche virus in pregnancy, with a focus on travel-related risk, counselling, testing, and follow-up care.

SOGC Online Courses

Eliminating Cervical Cancer – Once and Forever
An online course that reviews HPV epidemiology, vaccine safety and effectiveness, and practical approaches to counselling on HPV vaccination.

Vaccination in Pregnancy
An online course that reviews the safety and effectiveness of vaccination during pregnancy, as well as key counselling, storage, and administration considerations across the preconception, pregnancy, and postpartum periods.

Websites

Public Health Agency of Canada: Infectious Diseases
A Government of Canada resource hub that provides information on infectious diseases, including prevention, surveillance, and public health guidance.

Canadian Immunization Guide
A Government of Canada resource that provides evidence-based recommendations on immunization practices, vaccine use, and special considerations across populations and clinical situations.

CATIE - (HIV and Hepatitis C Resources)
A Canadian resource hub that provides evidence-based information, education, and practical tools related to HIV, hepatitis C, sexual health, and substance use.

Committee to Advise on Tropical Medicine and Travel (CATMAT): Statements and Publications
A Government of Canada resource hub that provides expert guidance, statements, and publications on tropical medicine and travel health for travellers and health care professionals.

Patient Resources

Immunize Canada
A Canadian immunization resource hub that provides evidence-based information, educational tools, and provider resources to support vaccine confidence and informed decision-making.

SexandU.ca
An SOGC sexual and reproductive health resource hub that provides evidence-based information, tools, and resources on contraception, fertility, pregnancy, and sexual health.

HPVinfo.ca
An SOGC resource hub that provides evidence-based information on HPV, including prevention, symptoms, treatment, and related resources for the public.

Resources for Patients

Vaccinations Before and During Pregnancy
An SOGC and Canadian Pharmacists Association resource that outlines key immunization considerations before and during pregnancy to support informed preconception and prenatal care.

Immunization and Vaccines in the Preconception Period
An SOGC and Canadian Public Health Association resource that highlights key immunization considerations before pregnancy to support informed preconception care.

The Society of Obstetricians and Gynaecologists of Canada (SOGC)