Pregnancy planning: what tests are needed and why

The preconception period is the best time to identify and manage risk factors: treat infections, update vaccinations, correct chronic conditions and deficiencies, and, if necessary, discuss genetic risks. This reduces the risk of complications for both mother and fetus and increases the likelihood of a healthy pregnancy. [1]

International guidelines emphasize that some screenings should be performed for everyone, while others should be tailored based on individual risk factors, age, family history, and the epidemiological situation. The one-size-fits-all approach of "one set of tests for everyone" is outdated; the emphasis is on personalization. [2]

A separate section of preconception preparation includes testing for vaccine immunity to vaccine-preventable diseases and routine vaccinations before pregnancy, as some live vaccines are contraindicated after conception. Immunity verification and timely immunization before pregnancy reduce the risk of congenital infections. [3]

Finally, it is helpful to discuss genetic screening for common monogenic diseases and hemoglobinopathies before conception so that the couple understands their reproductive options in advance and can make informed decisions. [4]

What Most People Need to Check: Basic Preconception Screening

Most adults should be tested for HIV at least once, as universal age-specific screening is recommended by reputable prevention services; if your status is unknown, this is especially important before planning a pregnancy to protect your unborn child. [5]

A one-time screening for hepatitis C virus is recommended for all adults across a wide age range if they have not previously been tested; if risk factors are present, the physician may recommend repeat testing. Detection and treatment reduce risks to the mother and fetus. [6]

Screening for chlamydia and gonococcal infections is recommended for all sexually active women under 25 years of age, and for those 25 years and older if they have risk factors. These infections are often asymptomatic but are associated with pelvic inflammatory disease and adverse pregnancy outcomes. [7]

Weight and blood pressure monitoring are combined with screening for prediabetes and diabetes in adults aged 35 to 70 who are overweight or obese; if risk factors are present, the physician may recommend earlier screening. Preconceptional detection of carbohydrate metabolism disorders allows for safe pregnancy and reduces the risk of birth defects. [8]

Table 1. Basic tests when planning pregnancy

Direction	Who is it indicated for?	What are we handing over?	For what	Repeat
HIV	Once for everyone, more often in case of risks	Immunoassay test for HIV	Early diagnosis and prevention of vertical transmission	By risks
Hepatitis C	All adults 18-79 years old	HCV antibodies with RNA confirmation in case of positive screening	Treatment reduces risks for mother and fetus	By risks
Chlamydia, gonorrhea	Everyone under 25 years old; over 25 years old - at risk	Nucleic acid amplification test	Prevention of inflammatory complications and adverse outcomes	By risks
Prediabetes and diabetes	35-70 years old with overweight or obesity	Fasting glucose or HbA1c	Reducing the risk of developmental defects and complications	By risks
[9]

Immunity and vaccinations before conception

Before pregnancy, it is important to confirm immunity to rubella and chickenpox. If immunity is not present, vaccination is administered before conception, and then an interval of at least 28 days is observed before attempting to conceive. These measures prevent birth defects and severe neonatal infections. [10]

Live vaccines are contraindicated during pregnancy, so vaccinations against measles, mumps, rubella, and chickenpox are scheduled in advance. Routine pregnancy testing is not required before these vaccines; advice to delay conception for 28 days is sufficient. [11]

During the preconception visit, the doctor will also check the relevance of other vaccinations according to the age schedule and the epidemiological situation. If immunity is not present, vaccinations are administered before pregnancy, taking into account the type of vaccine, exposure risks, and regional recommendations. [12]

Some healthcare systems further emphasize the practice of checking laboratory status for rubella and chickenpox before planning a pregnancy, as serology interpretation may be less reliable during pregnancy. This is organizationally convenient and improves the safety of the expectant mother and child. [13]

Table 2. Immunity and vaccinations before pregnancy

Infection	What to check	If there is no immunity	Interval before conception
Rubella	IgG or proof of 2 doses of MMR	MMR vaccine	Not less than 28 days
Chicken pox	IgG or 2 doses document	Chickenpox vaccine, 2 doses	Not less than 28 days
Other vaccines	According to the calendar and risks	According to the readings	According to the instructions
[14]

Sexually transmitted infections: who needs what tests

Screening for chlamydia and gonorrhea is recommended for all sexually active women under 25, and for those older, if at risk. The method of choice is a nucleic acid amplification test on genitourinary tract or urine samples. Early diagnosis and treatment before conception reduce the risk of tubal factors and pregnancy complications. [15]

Syphilis screening is performed on people at increased risk. Determining status before conception is important, as timely treatment prevents severe adverse outcomes for the fetus. The physician determines the frequency of repeat testing based on epidemiological and individual risk factors. [16]

HIV testing is recommended for all adults at least once, and then based on risk. Detection and treatment before conception can achieve an undetectable viral load and dramatically reduce the risk of vertical transmission. [17]

Screening for hepatitis C virus is recommended for all adults, with subsequent confirmation of positive results and treatment as indicated. Detection before pregnancy helps minimize perinatal risks and plan follow-up. [18]

Table 3. STI screening when planning pregnancy

Test	To whom	Method	For what
Chlamydia	Everyone under 25; older - according to risk	Nucleic acid test	Prevention of complications and infertility
Gonorrhea	Likewise	Nucleic acid test	Prevention of complications
Syphilis	By risks	Serology	Prevention of congenital syphilis
HIV	Everyone at least once	Immunoassay	Prevention of vertical transmission
Hepatitis C	To all adults	Antibodies with RNA confirmation	Treatment and risk reduction
[19]

Genetic carrier screening: before conception is more convenient

Couples planning a pregnancy should be offered genetic carrier screening. Historically, testing was offered based on ethnicity or family history, but modern approaches recommend offering screening to everyone, regardless of background. This increases detection and equity of access. [20]

The minimum set includes cystic fibrosis and spinal muscular atrophy for all, as well as hemoglobinopathies. The need for universal testing for hemoglobinopathies in all women planning a pregnancy is emphasized due to the limitations of the ancestry approach. [21]

Expanded panels can cover dozens or hundreds of conditions, but panel selection and interpretation of results require consultation and, if necessary, genetic counseling. It is important to test in pairs: if one partner is a carrier, the other is offered testing. [22]

The advantage of preconception testing is that the couple has more time to make an informed decision: natural conception without additional interventions, IVF with preimplantation genetic diagnosis, using donor material, or adoption. [23]

Table 4. Genetic screening for carriage

Direction	To whom	What to discuss	Comments
Cystic fibrosis	To everyone	CFTR panel	Universal recommendation
Spinal muscular atrophy	To everyone	SMN1	Universal recommendation
Hemoglobinopathies	To everyone	Electrophoresis or molecular test	A universal approach instead of ancestry
Advanced panels	At the couple's request	Multigene panels	With gene counseling
[24]

Endocrine and metabolic tests

If risk factors are present, carbohydrate metabolism is monitored before conception. For individuals with established diabetes before pregnancy, a goal of HbA1c below 6.5% is set in the absence of severe hypoglycemia, and any associated complications are also assessed. This reduces the risk of birth defects and adverse outcomes. [25]

For women with known hypothyroidism or fertility problems, it is advisable to have their thyroid-stimulating hormone (TSH) assessed before conception and, if necessary, adjust levothyroxine therapy to ensure TSH is within the "target" range associated with better reproductive outcomes. For patients undergoing assisted reproductive technology (ART) programs, a TSH level of less than 2.5 mIU/L is often targeted. [26]

Routine universal thyroid function screening in everyone without symptoms or risk factors is controversial; guidelines recommend a balanced, selective approach based on history and symptoms. The decision to test is made by a physician after assessing the risk profile. [27]

All women planning a pregnancy are advised to take folate supplements in advance, but this is a matter of prevention, not laboratory testing. Folate dosage is adjusted based on risk, and laboratory tests for folate and vitamin B12 are performed as needed, such as when a deficiency is suspected. [28]

Table 5. Endocrine and metabolic tasks of the preconception stage

Direction	To whom	What are we doing?	Target
Carbohydrate metabolism	Risks include a history of diabetes	Glucose or HbA1c	HbA1c below 6.5% when planning
Thyroid gland	According to the readings	Thyroid-stimulating hormone, antibodies as indicated	Optimizing preconception function
Folates	For everyone as a preventative measure	Taking folic acid	Reducing the risk of neural tube defects
[29]

Blood and the Rh factor: what's useful to know before conception

During the first prenatal visit, all pregnant women undergo ABO blood typing and Rh determination, as well as antibody screening. Knowing your Rh status in advance helps you understand the need for Rh sensitization prevention and plan your care. [30]

If a woman is Rh-negative, anti-D immunoprophylaxis is administered throughout pregnancy according to standard protocols. It is important for a woman to know her status before conception and, if she has a history of transfusions, pregnancy losses, or invasive procedures, to inform her doctor. [31]

If antibodies are detected before conception, the strategy changes: the woman is referred for specialized monitoring to assess the risk of hemolytic disease of the fetus and newborn. These situations are rare, but preconception verification simplifies the process. [32]

Guidelines do not require a separate "universal" screening for iron deficiency outside of risk factors, but a complete blood count before conception may be useful for clinical reasons. The decision is made by the physician based on the patient's medical history, diet, and symptoms. [33]

Table 6. ABO, Rhesus, and antibodies: what to consider

What	When to know	Next steps
ABO and Rhesus	It is advisable to know before conception, and definitely during the first prenatal visit.	In case of Rh-negative status, immunoprophylaxis is planned.
Antibody screening	At the first prenatal visit; before conception - as indicated	If antibodies are detected, specialized monitoring is required.
[34]

Tests for men: partner's contribution

Preconception preparation involves both partners. For the man, it's important to discuss his vaccination status, undergo testing for sexually transmitted infections using the same risk criteria, and, if conception has been delayed for a long time, schedule a fertility assessment as indicated. This approach reduces the infectious risks for the woman and the unborn child. [35]

Genetic carrier screening is best organized at the couple level: if a woman is a carrier, her partner is tested for the same mutation to determine the risk to offspring and reproductive options. This is faster and more effective than sequential, separate tests. [36]

Screening for HIV, hepatitis C, and other infections in men should also be performed according to universal or individual indications, as with women. Early diagnosis and treatment before conception are important for the safety of the partner and the child. [37]

If a man has risk factors for carbohydrate metabolism disorders, it is also beneficial to be assessed for prediabetes and diabetes. Improving metabolic health in a couple has a positive impact on the chances of conception and pregnancy outcomes. [38]

Table 7. Preconception tasks for a man

Direction	What to discuss	When
Vaccinations	According to the calendar and contact risks	Before planning
STIs	HIV, hepatitis C, chlamydia, gonorrhea - according to criteria	Before planning
Genetics	Paired carrier screening	Before planning
Metabolic health	Screening for prediabetes and diabetes by risk	Before planning
[39]

What you usually shouldn't do: "TORCH panels" and controversial tests

Routine "TORCH screening" before or during pregnancy is not recommended. In particular, universal serological testing for cytomegalovirus has limited clinical value due to false-positive IgM and the lack of effective population-based preventive interventions. Hygienic measures to reduce exposure are far more beneficial. [40]

Routine screening for toxoplasmosis in countries with low seroconversion is also not recommended. Education on preventive measures and clinically indicated assessment are preferable to indiscriminate mass testing. [41]

Screening for parvovirus B19 and a number of other intrauterine infections is not performed "for everyone," but rather based on indications—based on exposure, symptoms, or ultrasound findings in the fetus. This reduces the number of false-positive results and unnecessary interventions. [42]

Screening for thrombophilia before conception without a personal or significant family history of venous thrombosis is generally not indicated. This selective approach is consistent with modern preventive medicine and helps avoid overdiagnosis. [43]

Table 8. Tests that are not routinely recommended

Test	Comment
TORCH panel	Not routinely indicated; selective approach
Cytomegalovirus, serology	Universal screening is not recommended.
Toxoplasmosis, serology	Universal screening is not recommended.
Parvovirus B19	Only in case of exposure or findings
Hereditary thrombophilias	Based on anamnesis, not everyone in a row
[44]

How to prepare for a visit and how often to retake the test

Gather information about vaccinations, past infections, family history, and chronic illnesses. This will allow your doctor to create a personalized screening plan: what's essential right now, and what can be postponed or avoided altogether. This plan takes into account age, lifestyle, contacts, travel, and regional risks. [45]

If HIV and hepatitis C testing has never been performed before, it's convenient to include them once before planning. Chlamydia and gonorrhea testing is repeated based on risk, age, and partner change. Prediabetes and diabetes screening is repeated at intervals agreed upon with the physician, taking into account body weight and other factors. [46]

Genetic carrier screening is usually performed once per lifetime; if a partner changes, repeat couple testing or a reconsideration of the strategy may be necessary. Vaccinations with live vaccines are administered in advance, with a minimum interval before conception. [47]

For patients with diabetes, thyroid disease, and other chronic conditions, it is helpful to agree on treatment goals before conception and a monitoring plan early in pregnancy. This reduces the risk of complications and increases the chances of a favorable outcome. [48]

A quick checklist for a couple

1. Confirm immunity to rubella and chickenpox, if necessary, get vaccinated and wait 28 days. [49]
2. Get screened once for HIV and hepatitis C if you haven't already. [50]
3. Get tested for chlamydia and gonorrhea: everyone under 25, older - according to risk. [51]
4. Discuss genetic carrier screening and universal testing for hemoglobinopathies. [52]
5. If indicated, check carbohydrate metabolism and thyroid function and adjust therapy before conception. [53]

Frequently asked questions

Should everyone undergo TORCH screening before pregnancy?
No. Universal TORCH screening is not recommended. A selective approach is used: risk assessment, prevention training, and testing for exposure or clinical findings. [54]

When to get vaccinated if you're not immune?
Before conception. Live vaccines, such as those against rubella and chickenpox, are contraindicated during pregnancy. After vaccination, wait at least 28 days before trying to conceive. [55]

Is genetic screening mandatory?
It's an option that should be offered to all couples. The minimum screening includes cystic fibrosis, spinal muscular atrophy, and hemoglobinopathies; further screening is optional and should be done after consultation. [56]

Why know your Rh status before pregnancy?
To understand the need for anti-D immunoprophylaxis and to inform your doctor in advance about factors that increase the risk of sensitization. In any case, ABO, Rh, and antibody screening will be performed during the first prenatal visit. [57]