The preconception office visit

INTRODUCTION — Preconception care is a broad term that refers to the process of identifying behavioral, environmental, biomedical, and social risks to an individual's fertility and pregnancy outcome with the goal of reducing these risks through education, counseling, and appropriate intervention [1].

Barriers to providing preconception care at the office level include time constraints due to competing priorities within the practice setting, lack of resources to assist with conveying information, and lack of adequate reimbursement for screening tests and counseling [2]. Preconception care screening tools and online informational resources can help with some of these logistics.

At the patient level, it is important to recognize that most females do not schedule a preconception care visit. Factors that facilitate uptake of preconception care include adequate health insurance coverage, the availability of patient informational resources such as brochures and handouts, and waiting room posters outlining the benefits and availability of preconception care consultations. Preconception care may not be an option for patients in some resource-limited areas. In Malawi, for example, it is not a key component of maternal and child health policy. In a study of over 4000 pregnant individuals, nearly two-thirds took no actions to prepare for their pregnancies and among the one-third who did, eating more healthily (72 percent) and saving money (43 percent) were the most common forms of preparation [3].

This topic will discuss preconception care in cisgender women. Prenatal care is reviewed separately (see "Prenatal care: Initial assessment" and "Prenatal care: Second and third trimesters"). Reproductive planning in sexual minority women (eg, lesbian, gay, bisexual, transgender, queer, and other women, or LGBTQ+) is also reviewed separately. (See "Sexual and gender minority women (lesbian, gay, bisexual, transgender, plus): Medical and reproductive care", section on 'Reproductive health and parenting issues' and "Sexual and gender minority women (lesbian, gay, bisexual, transgender, plus): Medical and reproductive care", section on 'Prevention of unintended pregnancy'.)

TARGET POPULATION — Preconception care should be an essential part of primary and preventive care for all females of childbearing potential who present for a periodic health examination [1,4,5], whether or not they are currently interested in conceiving. In addition to the periodic health evaluation, potential opportunities for preconception care occur during many nonemergency health care encounters, including:

●Premarital office visit

●Contraception counseling and provision

●After a negative pregnancy test

●Evaluation for sexually transmitted disease or vaginal infection

●Postpartum office visit

●Office visit related to pregnancy termination

Routinely addressing preconception issues in all females of childbearing potential is important for several reasons:

●Although many females intend to obtain preconception evaluation and counseling before attempting pregnancy, almost 50 percent of pregnancies in the United States are unintended [6].

●For prevention of congenital anomalies, preconception intervention (eg, folic acid supplementation, avoidance of alcohol and some medications) is more important than prenatal intervention since as many as 30 percent of pregnant individuals begin traditional prenatal care in the second trimester (≥14 weeks 0 days of gestation), which is after the primary period of organogenesis (between 3 and 10 weeks of gestation) (figure 1).

●Some interventions can take months to achieve the desired result (eg, optimization of medical conditions, substantial weight loss).

Omission of preconception counseling and intervention in females of childbearing potential who state that they are not planning to become pregnant may explain, in part, why unintended pregnancies are associated with more adverse maternal and infant outcomes than intended pregnancies [7].

GENERAL APPROACH — Ideally, the patient and their clinician create a reproductive health plan, which will be reviewed and revised, as needed, at each visit. As part of that plan, they should be asked about their intention to become pregnant and offered contraception that meets their current contraceptive needs while taking into account the timing of a planned first or subsequent pregnancy ("Would you like to become pregnant in the next year?"). Contraception should continue to be addressed at all medical visits of reproductive-age individuals of childbearing potential.

Primary care teams should be able to perform a basic preconception assessment, provide basic preconception education, and offer appropriate recommendations for intervention, as described below [8-10]. Situations beyond the clinician's expertise should prompt consideration of referral to a genetic counselor and/or other specialty care. Coordination of care among these clinicians is an important component of effective intervention.

Resources — Informational resources on preconception care are available online at no cost from several sources, including:

●Centers for Disease Control and Prevention

●March of Dimes

●American College of Obstetricians and Gynecologists

●Perinatal Foundation

GOALS — The three major goals of preconception care are to:

●Identify potential risks to the mother, fetus, and pregnancy.

●Educate the individual about these risks, options for intervention and management to reduce risk, and reproductive alternatives.

●Initiate interventions to provide optimum maternal, fetal, and pregnancy outcomes. Interventions include motivational counseling, disease optimization, and specialist referral.

There is limited evidence as to the best means for achieving these goals [1,11-13].

RISK ASSESSMENT AT THE PRECONCEPTION OFFICE VISIT — The key task in risk assessment is to obtain a thorough history. Several paper and computerized questionnaires and record forms are commercially available for this purpose (see 'Resources' above). Patient education and medical interventions can be initiated based on this information.

Age — As maternal age increases, the risks for infertility, fetal aneuploidy, miscarriage, gestational diabetes, preeclampsia, and stillbirth also increase [14]. Individuals should be aware of these risks and the consequences of delaying conception until they are in their 30s or 40s, and consider this in their reproductive health plans. (See "Effects of advanced maternal age on pregnancy" and "Management of pregnancy in patients of advanced age".)

Advanced paternal age also has some risks for offspring. (See "Effect of advanced paternal age on fertility and pregnancy".)

History — A thorough medical history is a good starting point for discussing how pregnancy can affect maternal health and the effect of maternal health and behavior on the fetus and pregnancy.

Components — Guidelines generally target the following areas for preconception risk assessment [1]:

●Chronic medical problems (including obesity) – Although it makes intuitive sense that identifying and treating medical conditions, including obesity and mental health issues, prior to pregnancy is beneficial, few randomized trials have evaluated the efficacy of preconception health promotion interventions for improving pregnancy outcome.

●Medications known to be teratogens – A key component of medical assessment is to identify use of medications (including over-the-counter and prescription drugs) that are teratogenic and may be stopped (eg, warfarin), should be stopped (eg, isotretinoin), or can be changed to one that is safer for the pregnant individual or fetus (eg, extended-release nifedipine instead of lisinopril). It is especially important to elicit exposure to dietary supplements (eg, herbal supplements), as patients may not perceive them as medications that can be harmful to the fetus. Information on the pregnancy implications of drugs is available in the UpToDate drug database and from other resources. However, human teratogenic risk is undetermined for 98 percent of the drugs approved for human use and only approximately 30 drugs are considered to be proven as safe in pregnancy. Most of these are vitamins, minerals, electrolytes, and hormone replacement (eg, levothyroxine) at physiological doses. Therefore, the potential risk of medication use has to be considered on a case-by-case basis in terms of the harm of discontinuing the drug and the availability of alternative drugs. (See 'Resources for information on potential teratogens' below.)

Medications used by the biologic father may affect the number and quality of sperm and thus male fertility, but a causal relationship with congenital anomalies is unusual and poorly defined [15]. Males exposed to cytotoxic or mutagenic substances are generally advised to wait six months (at least two sperm cycles) before attempting conception, but the range varies and depends on the specific drug [16]. For example, males taking thalidomide can have the drug in their semen and are advised to use a latex or synthetic condom during any sexual contact with females of childbearing potential and for up to 28 days following discontinuation of therapy. Males taking cyclophosphamide can have damage to sperm through DNA alterations; therefore, this medication should be avoided for three months before conception in males attempting to father a child [17].

●Reproductive history (table 1) – The gynecologic and obstetric histories are important for identifying factors that may contribute to infertility or complications in a future pregnancy and initiating appropriate intervention to reduce or eliminate these risks, if possible [18]. Use of contraception should be discussed to help ensure that pregnancy occurs at an appropriate time with respect to both personal choice and medical optimization.

●Genetic risks and conditions and family history (eg, increasing maternal age is associated with increasing risk for aneuploidy in offspring) (see "Genetic counseling: Family history interpretation and risk assessment" and "Preconception and prenatal panethnic expanded carrier screening" and "Preconception and prenatal carrier screening for genetic disorders more common in people of Ashkenazi Jewish descent and others with a family history of these disorders").

●Substance use, including nicotine-containing products, tetrahydrocannabinol (THC), alcohol, opioids, and nonprescribed drugs (see "Substance use during pregnancy: Screening and prenatal care" and "Opioid use disorder: Overview of treatment during pregnancy" and "Tobacco and nicotine use in pregnancy: Cessation strategies and treatment options").

●Infectious diseases and vaccinations (see "Immunizations during pregnancy").

●Nutrition (type of diet and intake, vitamins, supplements) and weight management (see 'Diet and supplements' below)

●Physical activity, exercise routine (see "Exercise during pregnancy and the postpartum period").

●Environmental hazards and toxins (eg, nonuse of safety belts; exposure to firearms, occupational hazards, infection; travel; hobbies; pets) (see 'Environmental exposures' below).

●Social and mental health concerns (eg, depression, social support, intimate partner violence and other safety issues, unstable housing, food insecurity) (see 'Psychosocial issues' below).

●Major surgical procedures.

Environmental exposures — Questions about the individual's work, travel, hobbies, pets, and home environment can identify potentially toxic exposures (including endocrine disruptors), such mercury, lead, pesticides, air pollution, household cleaning products, unsafe sources of water, plastics used for food storage, and infection (eg, Zika, Chagas disease) [19]. In addition to occupational exposures, mercury may be found in fish and skin-lightening creams, and lead may be detected in paint (pre-1970), imported cosmetics/food additives/medicine, and clay [20]. Of note, there is no convincing evidence that exposure to common sources of electromagnetic field radiation, such as computer monitors, electric blankets, heated water beds, cell phones, and microwave ovens, is harmful [21].

In the United States, the Occupational Safety and Health Administration (OSHA) sets and enforces standards requiring employers to provide a workplace free from recognized hazards likely to cause serious physical harm. This information should be available at the patient's workplace. (See "Overview of occupational and environmental health" and "Overview of occupational and environmental risks to reproduction in females" and "Working during pregnancy".)

Cytomegalovirus, Zika, rubella, syphilis, toxoplasmosis, herpes simplex virus, and varicella are infections with teratogenic potential. Congenital Chagas disease can cause early or late morbidity in offspring. Modes of transmission are discussed in individual topic reviews on each infection. Clinicians and patients should be aware of the places where Zika is endemic and the ways that Zika virus is transmitted (eg, mosquito bite, sex) and take appropriate precautions to avoid Zika virus infection during pregnancy. While COVID-19 is a relatively new virus, it does not appear to be associated with congenital anomalies. (See "Zika virus infection: An overview" and "Zika virus infection: Evaluation and management of pregnant patients" and "Chagas disease: Acute and congenital Trypanosoma cruzi infection".)

Resources for information on potential teratogens

●National Library of Medicine (NLM)

Bethesda, MD

800-638-8480

●Reproductive Toxicology Center

REPROTOX

Columbia Hospital for Women Medical Center

Washington, DC

202-293-5137

●Teratogen Information System

TERIS and Shepard's Catalog of Teratogenic Agents

Seattle, WA

206-543-2465

●Pregnancy Exposure Registries

●The Teratology Society's MotherToBaby fact sheets

866-626-6847

●Pediatric Environmental Health Specialty Units (PEHSU)

Physical examination — In healthy females, a reasonable preconception physical examination includes assessment of the heart, breasts, lungs, thyroid, abdomen, mouth, and genital tract, as well as blood pressure and body mass index (BMI). This examination is a pragmatic approach to detection of the most common conditions that can affect maternal health and pregnancy outcome.

Laboratory assessment

●Human immunodeficiency virus (HIV) counseling and screening are recommended for all females planning pregnancy (patients may opt out) because treatment of maternal HIV infection can reduce the risk of congenital infection [1]. (See "Prenatal evaluation of women with HIV in resource-rich settings".)

●Screening for gonorrhea, chlamydia, syphilis (table 2); hepatitis B and C (table 3 and table 4); and other sexually transmitted infections is performed according to standard guidelines. Depending on the disease, untreated infections can cause subfertility/infertility, as well as congenital infection and medical and pregnancy complications [1]. (See "Screening for sexually transmitted infections" and "Prenatal care: Initial assessment", section on 'Hepatitis C'.)

●Document rubella immunity or lack of immunity, if not previously performed. Evidence of immunity consists of laboratory evidence of rubella immunity, laboratory confirmation of disease, documentation of vaccination with at least one dose of live rubella virus-containing vaccine at age ≥12 months [22]. Rubella infection in pregnancy can have serious adverse effects on the fetus and can be prevented by prepregnancy immunization (immunization with a live vaccine cannot be performed in pregnancy). (See "Immunizations during pregnancy", section on 'Preconception immunization'.)

●Document varicella immunity or lack of immunity, if not previously performed. Evidence of immunity consists of a clinician's diagnosis of varicella or verification of history of varicella disease, documented vaccination, or laboratory evidence of immunity. Varicella infection in pregnancy can have serious adverse effects on the fetus and can be prevented by prepregnancy immunization (immunization with a live vaccine cannot be performed in pregnancy). (See "Immunizations during pregnancy", section on 'Preconception immunization'.)

●Screen for Chagas disease in females of reproductive age in the United States who were born in or lived in a region of Mexico or South or Central America with endemic Chagas disease (table 5). Individuals with Chagas disease are often unaware of their infection and its potential seriousness, including maternal cardiovascular and gastrointestinal complications, transmission to the fetus, and hydrops fetalis. Prepregnancy diagnosis and treatment can improve maternal outcomes and prevent mother-to-child transmission. For these reasons, an expert working group now recommends screening for Chagas disease in females of reproductive age in the United States who were born in or lived in a region of Mexico or South or Central America with endemic Chagas disease [23]. Ideally, screening is performed before pregnancy because antitrypanosomal drugs are contraindicated during pregnancy. (See "Chagas disease: Epidemiology, screening, and prevention", section on 'Screening for chagas disease in nonendemic clinical and community settings'.)

●Genetic carrier screening may be based upon the patient's or the potential biologic father's medical history or family history of heritable disease, ethnic origin, or patient request. Ideally carrier screening is performed before pregnancy as it can take considerable time to perform the test, and if appropriate, test the partner and arrange genetic counseling. This information allows individuals planning pregnancy to make informed reproductive decisions about adoption, gestational carrier pregnancy, use of donor sperm, in vitro fertilization with preimplantation genetic testing, avoidance of pregnancy, and prenatal diagnosis [24].

•(See "Preconception and prenatal carrier screening for genetic disorders more common in people of Ashkenazi Jewish descent and others with a family history of these disorders".)

•(See "Hemoglobinopathy: Screening and counseling in the reproductive setting and fetal diagnosis".)

•(See "Cystic fibrosis: Carrier screening".)

•(See "Fragile X syndrome: Prenatal screening and diagnosis".)

•(See "Spinal muscular atrophy", section on 'Pregnancy'.)

•(See "Preconception and prenatal panethnic expanded carrier screening".)

The simplest (but not most sensitive) screening test for hemoglobinopathies is review of red cell indices, as mean corpuscular volume (MCV) <80 fL may indicate that the individual is a carrier. (See "Hemoglobinopathy: Screening and counseling in the reproductive setting and fetal diagnosis".)

●Check glycated hemoglobin (A1C) in individuals with pregestational diabetes. Good glucose control (A1C <6.5 percent) in early pregnancy reduces the risk of miscarriage and congenital anomalies, and can take time to achieve. (See "Pregestational (preexisting) diabetes: Preconception counseling, evaluation, and management".)

●Screen for type 2 diabetes in individuals with risk factors for diabetes (table 6). Screening consists of a fasting plasma glucose, A1C, or both (table 7). (See "Screening for type 2 diabetes mellitus".)

●Test for latent tuberculosis in high-risk populations to avoid exposing the fetus to treatment, if indicated, during pregnancy. A tuberculin skin test or an interferon-gamma release assay (eg, QuantiFERON test) on blood may be used (table 8). (See "Tuberculosis infection (latent tuberculosis) in adults: Approach to diagnosis (screening)" and "Use of the tuberculin skin test for diagnosis of tuberculosis infection (tuberculosis screening) in adults" and "Use of interferon-gamma release assays for diagnosis of tuberculosis infection (tuberculosis screening) in adults".)

Testing for and treatment of latent tuberculosis infection should be pursued in individuals at risk for new infection and individuals at risk for progression from latent to active tuberculosis because of underlying conditions (table 9). A decision to test implies a decision to treat if the test is positive.

●Check a serum phenylalanine level if maternal phenylketonuria is known or suspected. Phenylalanine embryopathy can be prevented by dietary restriction of phenylalanine before and during pregnancy. The National Institutes of Health (NIH) Consensus Development statement recommended that plasma phenylalanine levels should be reduced to levels <6 mg/dL (360 micromol/L) at least three months before conception and remain at 2 to 6 mg/dL (120 to 360 micromol/L) during pregnancy [25]. (See "Overview of phenylketonuria".)

●Check a lead level if the patient is at high risk of lead exposure or an increased lead level, given the potential for adverse effects on the mother and fetus. The case definition for an elevated blood lead level for an adult is now defined as ≥5 mcg/dL by the National Institute for Occupational Safety and Health (NIOSH)/CDC's Adult Blood Lead Epidemiology and Surveillance (ABLES) program [26]. (See "Lead exposure, toxicity, and poisoning in adults" and "Prenatal care: Initial assessment", section on 'Lead level'.)

●Toxoplasmosis screening is controversial. Although national societies in the United States, Canada, and the United Kingdom advise against routine universal screening for toxoplasmosis during pregnancy, a prepregnancy baseline titer can be useful if screening is performed in patients with occupational exposure, pet cats, or high-risk eating habits. Patients with a negative toxoplasmosis titer should be counseled to avoid changing the cat litter, forgo eating undercooked meat, wear gloves when gardening, and frequently wash food, hands, and food preparation areas. (See "Toxoplasmosis and pregnancy".)

●Cytomegalovirus infection screening is also controversial. Knowledge of a negative titer in individuals at high risk of exposure (eg, work in child care facilities or dialysis units or have children in day care) may increase their motivation to practice good hygiene and decrease their risk of seroconversion during pregnancy. The highest risk of seroconversion is in mothers who have recently placed a toddler in day care. (See "Cytomegalovirus infection in pregnancy".)

Standard laboratory and other screening recommendations for the healthy adult population regardless of pregnancy plans are reviewed elsewhere.

INTERVENTIONS — Preconception interventions include health promotion education and counseling related to reproductive health risks, optimizing the control of medical disorders, and referral for specialized care, when appropriate. If pregnancy avoidance is desired, then contraceptive options should be discussed and a contraceptive chosen in line with the planned timing of pregnancy. (See "Contraception: Counseling and selection" and "Interpregnancy interval: Optimizing time between pregnancies".)

Available evidence, which is primarily observational data, supports an association between preconceptional counseling and positive changes in maternal behavior before pregnancy, particularly with respect to folic acid intake, improved glycemic control, and reduction in alcohol intake and cigarettes smoked [27-40]. There is also evidence from randomized trials that the prevalence of congenital anomalies was reduced by preconception care of females with diabetes [41] or epilepsy [42], while a cohort study supported a reduction in embryopathy in females with phenylketonuria who were placed on a strict low phenylalanine diet prior to conception [43]. In a trial in low- and middle-income neighborhoods in India, a package of health, nutrition, water, sanitation and hygiene, and psychosocial care interventions during the preconception period reduced the incidence of low birth weight compared with usual care [44]. In the United States, a secondary analysis of prospectively collected data from females without chronic diseases found that a prepregnancy healthy lifestyle was associated with a substantially lower risk of adverse pregnancy outcomes [45]. However, many individuals are unable to adopt a healthy lifestyle while attempting pregnancy [46,47].

Core interventions — The following core interventions can reduce the occurrence of congenital anomalies, congenital disease, impaired or excessive fetal growth, and a variety of pregnancy complications (eg, preterm birth, placental abruption) [27,41,48,49]. The evidence for the efficacy of these interventions is discussed in topic reviews on each intervention. Some interventions are effective if begun any time before conception, while glycemic control may take weeks to months to achieve, and substantial weight loss may take years. A recent focus of preconception care is to optimize prepregnancy cardiovascular health (ie, sleep duration, diet, physical activity, smoking cessation, BMI, blood pressure, cholesterol and glucose levels, psychological health), which may reduce the risks of both adverse pregnancy outcome and cardiovascular disease in the individual and their offspring [50].

●Folic acid supplementation and intake of folate fortified foods – Supplementation (400 to 800 mcg daily) and intake of fortified foods is recommended to reduce the risk of neural tube defects, and possibly other anomalies. (See "Preconception and prenatal folic acid supplementation".)

●Glycemic control and screening for diabetes comorbidities in females with diabetes – The American Diabetes Association recommends aiming for an A1C <6.5 percent (48 mmol/mol) prior to conception, if safely possible [51]. Euglycemia during pregnancy reduces the risks of congenital anomalies, miscarriage, preeclampsia, macrosomia, preterm birth, and other complications.

In addition, females with diabetes who take angiotensin-converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), and statins should discontinue use and switch to alternatives (when available) with a better fetal safety profile (eg, methyldopa, labetalol, calcium channel blocker). Most females on oral anti-hyperglycemic drugs should be switched to insulin. If an oral anti-hyperglycemic drug is maintained, it should be glyburide or metformin. (See "Adverse effects of angiotensin converting enzyme inhibitors and receptor blockers in pregnancy" and "Treatment of hypertension in pregnant and postpartum patients" and "Statins: Actions, side effects, and administration", section on 'Risks in pregnancy and breastfeeding' and "Pregestational (preexisting) diabetes: Preconception counseling, evaluation, and management", section on 'Glycemic control'.)

Evaluation for proliferative retinopathy is also indicated and, if present, should be treated prior to attempts at conception. (See "Pregestational (preexisting) diabetes: Preconception counseling, evaluation, and management", section on 'Preconception evaluation and management'.)

Given the complexity of these issues, preconception care is ideally provided at a multidisciplinary clinic including an endocrinologist, maternal-fetal medicine specialist, registered dietitian nutritionist, and diabetes care and education specialist, when available.

●Control of phenylalanine levels in females with phenylketonuria – Goal is less than 6 mg/dL for at least three months before conception and maintained at 2 to 6 mg/dL (120 to 360 micromol/L) during pregnancy to reduce the risk of embryopathy [25,52]. (See "Overview of phenylketonuria", section on 'Phenylalanine embryopathy (maternal PKU)'.)

●Abstinence from alcohol and opioid misuse – A safe level of alcohol intake during pregnancy has not been determined. Individuals who use alcohol or misuse opioids can be referred to a program for alcohol cessation or methadone- or buprenorphine-assisted treatment. (See "Alcohol intake and pregnancy" and "Substance use during pregnancy: Screening and prenatal care" and "Opioid use disorder: Pharmacologic management" and "Opioid use disorder: Overview of treatment during pregnancy".)

●Nicotine and tetrahydrocannabinol (THC) cessation – Individuals who are planning pregnancy may be more motivated to stop smoking and/or vaping and to utilize smoking cessation resources. Both nicotine and THC have known negative impacts on pregnancy, but data are limited. (See "Cigarette and tobacco products in pregnancy: Impact on pregnancy and the neonate" and "Tobacco and nicotine use in pregnancy: Cessation strategies and treatment options" and "Overview of smoking cessation management in adults" and "E-cigarette or vaping product use-associated lung injury (EVALI)".)

●Up-to-date vaccinations (figure 2 and figure 3 and table 10) – Vaccination protects against maternal and, in turn, congenital infection and provides passive protection to the newborn.

•Live vaccines (varicella; measle, mumps, rubella) should be administered at least one month prior to pregnancy. (See "Immunizations during pregnancy", section on 'Preconception immunization'.)

•All individuals who are pregnant or might be pregnant during the influenza season should receive the inactivated influenza virus vaccine as soon as it becomes available and before onset of influenza activity in the community, regardless of their stage of pregnancy. Pregnant individuals with influenza are more likely to develop severe illness and to die than the general population. (See "Seasonal influenza and pregnancy".)

•Ideally, the acellular pertussis vaccine is administered during pregnancy, rather than before conception to protect the infant from pertussis before it is eligible for vaccination. Maternal antibody levels wane quickly; vaccination between 27 and 36 weeks of gestation and at least one week before birth maximizes passive antibody transfer to the infant. (See "Immunizations during pregnancy", section on 'Tetanus, diphtheria, and pertussis vaccination'.)

•COVID-19 vaccination is recommended. Pregnancy itself is associated with an increased risk of severe infection and vaccine safety and efficacy have been established. (See "COVID-19: Vaccines" and "COVID-19: Overview of pregnancy issues", section on 'Vaccination in people planning pregnancy and pregnant or recently pregnant people'.)

●Weight reduction (or gain) to achieve a normal body mass index (BMI) – Obesity is associated with infertility; several adverse pregnancy outcomes, including congenital anomalies; and an increased risk of maternal health consequences. (See "Obesity in pregnancy: Complications and maternal management", section on 'Potential issues in pregnancy' and "Obesity in pregnancy: Complications and maternal management", section on 'Preconception counseling, evaluation, and care'.)

Underweight females (especially those with eating disorders) are at increased risk for anovulatory infertility and pregnancy complications. In one large cohort study, females with a suboptimal BMI had a 20 percent increase in risk for preterm birth and a 40 percent increase in risk of having a small for gestational age infant [53]. (See "Eating disorders in pregnancy".)

●Medication changes or discontinuation to avoid use of teratogens (table 11). (See 'Resources' above.)

●Avoidance of environmental teratogens (table 11). (See 'Resources' above.)

●Disease optimization (refer to individual topic reviews on each disease).

●Behavioral changes (eg, hand washing and other hygienic measures; avoiding consumption of undercooked meats and unpasteurized foods) can reduce the risk of acquiring infections, such as toxoplasmosis, cytomegalovirus, and listeriosis. (See "Toxoplasmosis and pregnancy" and "Cytomegalovirus infection in pregnancy" and "Treatment and prevention of Listeria monocytogenes infection".)

Mosquito avoidance measures (eg, clothing, repellants) are recommended to avoid arthropod-borne infections. (See "Prevention of arthropod and insect bites: Repellents and other measures", section on 'Pregnant women'.)

Exercise has many health benefits. Most patients should continue to exercise during pregnancy, with some modifications. (See "Exercise during pregnancy and the postpartum period".)

A healthy diet has life-long benefits. (See "Healthy diet in adults" and "Nutrition in pregnancy: Assessment and counseling".)

Interventions for selected risks

Maternal medical problems — Optimal management of maternal medical conditions, including changes in medications to those known to be safer in pregnancy, is important. Another key component is close follow-up and communication with specialist clinicians who are also involved in caring for the patient.

Some common or serious medical conditions other than diabetes (discussed above) that impact or are impacted by pregnancy are discussed briefly below; additional disorders are reviewed separately. (Refer to individual topic reviews on medical disorders, section on pregnancy.)

●Hypertension should be controlled prior to conception. Treatment is initiated at a blood pressure threshold of 140/90 mmHg using the fewest medications at the lowest effective dose to maintain blood pressure below this level. Individuals Certain agents, such as ACE inhibitors and ARBs, should be avoided in pregnancy, as their use at any stage of pregnancy is associated with adverse effects on the fetus. Patients who are on any of these agents should be advised to switch to agents whose safety in pregnancy is established. (See "Chronic hypertension in pregnancy: Prenatal and postpartum care" and "Adverse effects of angiotensin converting enzyme inhibitors and receptor blockers in pregnancy".)

Individuals who have long-standing or poorly controlled hypertension should be evaluated for end-organ effects (eg, ventricular hypertrophy, retinopathy, renal insufficiency) [54]. (See "Overview of hypertension in adults", section on 'Evaluation'.)

●Asthma should be under good control prior to attempting conception. If necessary, the use of steroids (inhaled and systemic) in pregnancy is generally safe, particularly when compared with the risk of maternal acid base disturbance and fetal hypoxemia in the event of bronchospasm. (See "Asthma in pregnancy: Clinical course and physiologic changes" and "Management of asthma during pregnancy".)

●Thyroid disease requires close monitoring of thyroid function as both hyper- and hypothyroidism can affect fertility and pregnancy outcome. Females who receive radioiodine should defer pregnancy for at least six months. (See "Overview of thyroid disease and pregnancy".)

●Females with a history of seizures and those taking antiseizure medications should receive thorough information about the risks of pregnancy for mother and fetus, adjustments in their drug regimen (if appropriate), and folic acid supplementation to reduce the risk of neural tube defects (dose depends on antiseizure medication regimen). In particular, valproate should be discontinued if seizures can be adequately controlled with an alternative drug, since valproate appears to be a more potent teratogen than other antiseizure medications (figure 4). (See "Management of epilepsy during preconception, pregnancy, and the postpartum period".)

●Pregnancy can pose additional risks to females with cardiovascular disease (congenital or acquired) that should be addressed before conception. Cardiovascular disease is the most common cause of indirect maternal mortality and is responsible for over one-third of pregnancy-related maternal deaths [55]. For females with some cardiac conditions, pregnancy can be life-threatening and should be avoided. Patients taking statins are advised to discontinue them. Patients taking warfarin are switched to heparin. (See "Acquired heart disease and pregnancy" and "Pregnancy in women with congenital heart disease: General principles".)

Maternal cardiovascular health also has implications for offspring. In a multinational cohort study, poor maternal cardiovascular health metrics (as defined by BMI, blood pressure, total cholesterol level, glucose level, and smoking) at approximately 28 weeks of gestation was associated with poor cardiovascular health metrics in offspring examined at 10 to 14 years of age [56]. No single maternal metric drove the association, which may be related to epigenetic modifications in utero, as well as genetic susceptibility and household lifestyle. Improving maternal cardiovascular health metrics is beneficial for the mother and, if achieved before and maintained throughout pregnancy, may improve offspring cardiovascular health metrics as well.

●For females with systemic lupus erythematosus, the prognosis is best when the disease has been quiescent for at least six months prior to pregnancy and the patient's underlying renal function is stable and normal or near normal. Maternal medications may need to be changed because of potential fetal risks. For example, mycophenolate increases the risk of first-trimester pregnancy loss and congenital malformations, including cleft lip and palate, as well as anomalies of the distal limbs, heart, esophagus, and kidneys. This medication should be avoided during pregnancy. (See "Pregnancy in women with systemic lupus erythematosus" and "Safety of rheumatic disease medication use during pregnancy and lactation".)

●Females with inherited thrombophilias are at higher risk of thromboembolic complications during pregnancy because of pregnancy-associated changes in several coagulation factors; in some cases, they are at increased risk of adverse pregnancy outcome, as well. Indications for, and management of, anticoagulation should be addressed with a thrombosis specialist. (See "Inherited thrombophilias in pregnancy".)

●Ideally, any female with a history of anaphylaxis should be referred to an allergy specialist for evaluation prior to pregnancy. This is particularly important for those who experienced anaphylaxis in association with a previous medical or surgical procedure, as similar medications may be needed during labor and delivery. (See "Anaphylaxis during pregnancy and delivery".)

●Dental caries and other oral diseases (eg, periodontal disease) are common and may be associated with pregnancy complications, such as preterm delivery; thus, referral to a dentist is appropriate. (See "Spontaneous preterm birth: Overview of risk factors and prognosis".)

Heritable diseases — For couples at increased risk of offspring with a heritable disease, referral to a specialist in genetics is usually warranted to discuss the results of screening tests, risk of the disease in the fetus, the natural course of the disease, options regarding preimplantation and prenatal diagnosis and intervention, and reproductive alternatives. As options for prenatal diagnosis and reproductive alternatives are rapidly changing, a timely referral may be indicated even if the patient has had previous counseling. (See 'Laboratory assessment' above and "Preimplantation genetic testing".)

Psychosocial issues — Psychosocial stress, mental health, and financial issues should be identified and appropriate interventions taken with the help of a community resource specialist. It is particularly important to screen for the presence of intimate partner violence, lack of social support, and barriers to prenatal care [57]. (See "Intimate partner violence: Diagnosis and screening".)

Maternal psychiatric illness should be identified and treated, as appropriate, because untreated or inadequately treated disease will result in maternal suffering and could lead to a variety of consequences, such as poor compliance with prenatal care, poor nutrition, substance abuse, or disturbed relationships between the mother and infant [58]. Ideally, the patient should wait until they have become euthymic, which may take 6 to 12 months, before attempting to conceive [59].

Drugs used to treat psychiatric disease can affect the fetus and neonate. Females who have been on medication and have mild or no symptoms for six or more months may be considered for medication taper and discontinuation (eg, decrease medication by 25 percent every one to two weeks) [59]. Some individuals may benefit from psychotherapy. Discontinuation of pharmacotherapy is generally not advised for individuals with a history of severe recurrent depressive disorders, psychosis, bipolar illness, psychiatric comorbidity requiring pharmacotherapy, or a history of suicidal ideation. (See "Antenatal use of antidepressants and the potential risk of teratogenicity and adverse pregnancy outcomes: Selective serotonin reuptake inhibitors" and "Teratogenicity, pregnancy complications, and postnatal risks of antipsychotics, benzodiazepines, lithium, and electroconvulsive therapy".)

Diet and supplements

●Vitamins, supplements – As discussed above (see 'Core interventions' above), all females planning pregnancy or capable of becoming pregnant should be counseled to take supplemental folic acid to reduce the risk of having an infant with a neural tube defect [60,61], and possibly other congenital anomalies [62] and abruption [63,64]. The neural tube closes between 24 and 26 days after conception so folic acid supplementation after the diagnosis of pregnancy is usually too late to reduce the risk of neural tube defects. The most convenient method of folic acid supplementation is daily intake of a multivitamin containing 400 to 800 mcg of folic acid. (See "Preconception and prenatal folic acid supplementation".)

Megavitamins, nonessential dietary supplements, and herbal preparations should be discontinued, given that the risk to the fetus from such substances has generally not been evaluated. Megadoses of vitamin A taken during early pregnancy have been associated with congenital anomalies [65,66]. Multivitamin preparations containing more than 5000 international units of vitamin A should be avoided (increased risk of teratogenesis at >10,000 international units/day). (See "Nutrition in pregnancy: Dietary requirements and supplements".)

Many prenatal vitamins contain no iodine. Females planning pregnancy have been advised to supplement their diet with a daily oral multivitamin supplement that contains 150 to 250 mcg of iodine in the form of potassium iodide, although there is insufficient evidence of the benefits and harms of routine iodine supplementation. Using iodized salt (contains 95 mcg iodine per one-quarter teaspoon) and consuming seafood that is naturally rich in iodine are alternatives. (See "Nutrition in pregnancy: Dietary requirements and supplements", section on 'Iodine'.)

●Healthy diet – A healthy diet is generally the same whether or not an individual is planning pregnancy, with some exceptions. (See "Nutrition in pregnancy: Assessment and counseling", section on 'General principles of a healthy diet during pregnancy'.)

High caffeine intake should probably be avoided; experts suggest that females who are attempting to conceive (or who are pregnant) limit caffeine consumption to less than 200 to 300 mg per day. (See "Caffeine: Effects on reproductive outcomes in females".)

●Fish – The quantity and type of fish consumed should also be regulated and certain types of fish should be avoided during pregnancy and the preconception period due to concerns about possible teratogenic effects from environmental toxins, particularly mercury. Only cooked fish should be eaten. There is no clear evidence that n-3 (also known as omega-3) long chain polyunsaturated fatty acids (docosahexaenoic acid [DHA] and eicosapentaenoic acid [EPA]) supplements during pregnancy improve offspring neurodevelopment or other outcomes. (See "Fish consumption and marine omega-3 fatty acid supplementation in pregnancy" and "Nutrition in pregnancy: Assessment and counseling", section on 'Guidelines for safe seafood consumption'.)

Infertility, recurrent miscarriage, and adverse pregnancy outcome — The general consensus among infertility experts is that infertility evaluation should be undertaken for couples who have not been able to conceive after 12 months of unprotected and frequent intercourse, but earlier evaluation should be undertaken based on medical history and physical findings and in females over 35 years of age (table 12). (See "Overview of infertility".)

Ideally, the work-up for potential causes of adverse pregnancy outcome should be performed by the obstetrician-gynecologist as part of the antepartum or postpartum management of the affected pregnancy. Subsequent management depends on the cause. (Refer to individual topic reviews on miscarriage, recurrent pregnancy loss, preterm birth, preeclampsia, stillbirth, congenital anomalies, and other pregnancy complications.)

MEASURES OF SUCCESSFUL PRECONCEPTION CARE — A clinical workgroup of the National Preconception Health and Health Care Initiative proposed that achievement of the following nine targets at the first prenatal visit is indicative of quality preconception care [67]:

●Absence of tobacco use

●Absence of uncontrolled depression

●Absence of sexually transmitted infections

●Teratogen avoidance

●Healthy weight (body mass index [BMI] >18 and <30 kg/m²)

●Folic acid use beginning at least three months before conception

●Optimal glycemic control

●Planned pregnancy

●First prenatal visit before 12 weeks of gestation

Other groups have included other targets, such as reduction in low birth weight, small for gestational age, and preterm newborns [44] and postpartum use of a most or moderately effective method of contraception before planning another pregnancy. In a Pregnancy Risk Assessment Monitoring System (PRAMS) survey, older females (35 to 44 years), non-Hispanic Black females, and uninsured females were least likely to achieve one or more preconception health indicators [68]. Systemic efforts to improve preconception care may help these vulnerable populations as well.

PREGNANCY — Individuals should be counseled to make an appointment with an obstetric clinician as soon as they believe they are pregnant to accurately estimate the gestational age/delivery date and to initiate prenatal care. (See "Prenatal care: Initial assessment" and "Prenatal care: Patient education, health promotion, and safety of commonly used drugs".)

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Immunizations in adults".)

SUMMARY AND RECOMMENDATIONS

●Reproductive health planning – Cisgender women of childbearing age should develop a reproductive health plan. As part of routine health maintenance, they should be asked about their intention to become pregnant and offered contraception that meets their contraceptive needs. They should be made aware of fertility and pregnancy problems that increase with advancing age (table 12). (See 'Target population' above and 'Age' above.)

●Goals – The goals of preconception care are to (see 'Risk assessment at the preconception office visit' above):

•Identify potential risks to the mother, fetus, and pregnancy.

•Educate the individual about these risks, options for intervention and management for risk reduction, and reproductive alternatives.

•Initiate interventions to provide optimum maternal, fetal, and pregnancy outcomes. Interventions include motivational counseling, disease optimization, and specialist referral.

●Preconception history – Any one of several commercially available paper and computerized questionnaires and record forms designed for obtaining a thorough preconception history will help in identifying risks to the pregnant individual and their pregnancy. A preconception history includes review of (see 'History' above):

•Chronic diseases (eg, diabetes, hypertension, oral health)

•Medications known to be teratogens

•Reproductive history (table 1)

•Genetic conditions and family history

•Substance use, including tobacco, alcohol, and nonprescribed drugs

•Infectious diseases and vaccinations (table 2 and table 4 and table 9 and table 5)

•Nutrition, folic acid intake, and weight management

•Environmental hazards and toxins (table 11)

•Family planning

•Social and mental health concerns

●Medical assessment – A key component of medical assessment is to identify use of medications (including over-the-counter and prescription drugs) that are teratogenic and may be stopped, should be stopped, or can be changed to one that is safer for the pregnant individual or fetus (table 11). (See 'History' above.)

●Laboratory evaluation (See 'Laboratory assessment' above.)

•Screening for HIV, gonorrhea, chlamydia, syphilis (table 2); hepatitis B and C (table 3 and table 4); and other sexually transmitted infections is performed according to standard guidelines

•Document rubella immunity or lack of immunity

•Document varicella immunity or lack of immunity

•Screen for Chagas disease in females of reproductive age who were born in or lived in a region of Mexico or South or Central America with endemic Chagas disease (table 5)

•Genetic carrier screening may be based upon the patient's or the potential biologic father's medical history or family history of heritable disease, ethnic origin, or patient request

•Screen for pregestational diabetes in individuals with risk factors for diabetes (table 6) and check glycated hemoglobin (A1C) in individuals with pregestational diabetes

•Check a serum phenylalanine level if maternal phenylketonuria is known or suspected

•Test for latent tuberculosis in high-risk populations

•Check a lead level if the patient is at high risk of lead exposure or an increased lead level

●Core interventions – Core preconception interventions that can reduce the occurrence of congenital disorders, fetal growth abnormalities, and pregnancy complications include (see 'Core interventions' above):

•Folic acid supplementation and intake of fortified foods

•Glycemic control in females with diabetes; screening for diabetes in females with risk factors; evaluation for and treatment of proliferative retinopathy

•Control of phenylalanine levels in females with phenylketonuria

•Abstinence from alcohol and illicit drugs; nicotine and tetrahydrocannabinol (THC) cessation

•Achieve or maintain a healthy body mass index (BMI; 18.5 to 24.9 kg/m²)

•Medication changes to avoid use of teratogens

•Avoidance of environmental teratogens

•Disease optimization (see 'Maternal medical problems' above)

•Up-to-date vaccinations (figure 2 and table 10)

•Behavioral changes to reduce the risk of acquiring infections, such as toxoplasmosis, cytomegalovirus, and listeriosis; to achieve 150 min/week or more of moderate-to-vigorous physical activity; and consume a healthy diet.

●Assessing risk of heritable disorders – For females with a positive history for a heritable disease, referral to a specialist in genetic counseling is usually required to discuss carrier testing, the risk of genetic disease in the fetus, options regarding prenatal diagnosis and intervention, the natural course of the disease, and reproductive alternatives. (See 'Heritable diseases' above.)