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Preconception Counseling

Editor: Brian W. Jack Updated: 6/26/2023 10:54:46 PM

Introduction

The primary goals of preconception counseling and care are to educate individuals and couples, assess risks, optimize medical care, and offer interventions before pregnancy to minimize the likelihood of poor pregnancy-related outcomes. Nearly half of all pregnancies that occur annually are unplanned. Therefore, any encounter with a nonpregnant individual of reproductive potential should be considered an opportunity to discuss healthy habits. The American College of Obstetricians and Gynecologists (ACOG) recommends screening these individuals by asking, "Would you like to become pregnant in the next year?"[1] If so, preconception counseling is recommended; otherwise, contraceptive counseling is recommended.[1][2] Additionally, specific visits dedicated to preconception counseling should be recommended to all individuals desiring a pregnancy.[1]

Function

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Function

Preconception counseling can significantly reduce maternal and infant morbidity and mortality by optimizing health before pregnancy. To best accomplish this, ACOG and the American Society for Reproductive Medicine (ASRM) recommend clinicians:

  • Optimize medical management of all chronic diseases before conception, especially the following conditions:
    • Chronic hypertension
    • Pregestational diabetes
    • Obesity 
    • Thyroid disorders, particularly untreated hypothyroidism
    • Psychiatric disorders, especially mood disorders
    • Human immunodeficiency virus (HIV) infection
    • Thrombophilias
    • Autoimmune disease
    • Cardiopulmonary disorders
  • Review medications for safety, efficacy, and possible dosing adjustments.
  • Take a careful family history, provide genetic counseling, and offer patients genetic screening.
  • Assess immunization status and offer patients appropriate vaccinations.
  • Ensure cervical cancer screening is up-to-date.
  • Assess the need for sexually transmitted infection (STI) screening; treat any identified infections.
  • Assess and provide appropriate counseling regarding nutritional status, current weight, and optimal weight gain during pregnancy.
  • Screen for substance use and exposure to intimate partner violence (IPV).
  • Screen for teratogenic environmental or occupational exposures.
  • Discuss safe interpregnancy intervals in patients with a recent delivery.
  • Review previous pregnancy complications; discuss the risk of recurrence and strategies to reduce this risk potentially.[1][2][3]

In addition, providing appropriate patient education on diet and nutrition, supplements, travel, and safety during pregnancy may reduce risks to the fetus, especially in early pregnancy before the first prenatal visit, thereby establishing a foundation for a healthier pregnancy.

Issues of Concern

Pregnancy Planning and Spacing

Age-appropriate sex education is recommended for all individuals of reproductive age, including adolescents. Contraceptive counseling and education on STI prevention are essential for all people younger than 25, regardless of gender. Ideally, every couple should be able to choose when they are ready to attempt conception, as conscious family planning is vital for overall health and well-being in young adults.[4] Unplanned and unintended pregnancies frequently lead to delayed initiation of prenatal care, which can contribute to adverse events during pregnancy and poorer perinatal outcomes.[1]

Patients with a recent delivery should be counseled on the safest time between pregnancies or interpregnancy interval (IPI). ACOG and the Society for Maternal-Fetal Medicine (SMFM) recommend patients wait at least 6 months after delivery before attempting conception again, with an ideal interval of 18 months.[1][5] Short IPIs, especially those less than 6 months, are associated with higher rates of pregnancy complications. Interdelivery intervals (ie, the time between deliveries) of less than 18 months are associated with higher rates of uterine rupture in patients attempting a trial of labor after cesarean (TOLAC).[1][5] Patients with a recent history of bariatric surgery should wait for 12 to 24 months (after which the period of rapid weight loss slows) before attempting to conceive to mitigate potential negative effects on fetal growth. 

Management of Chronic Disease and Medication Review

Any woman with a chronic disease should review her desire to become pregnant with the managing clinician; all chronic conditions should be medically optimized, ideally before conception. 

Preconception counseling should focus on improving primary and secondary preventative interventions, treatment compliance, and overall well-being before becoming pregnant. Clinicians should review disease history and status, current medications, and social determinants of health (eg, limited support systems or financial barriers) that can affect an individual's ability to manage their condition. Pregnancy can increase risks for both mother and child, requiring additional visits, changes to established treatment plans, and other interventions.

Patients with chronic conditions such as seizure disorders, diabetes, cardiac or renal disease, autoimmune disorders, and other long-term illnesses should be referred to a high-risk obstetrical specialist (eg, Maternal-Fetal-Medicine) to discuss possible changes in medical management during pregnancy.[2]

Providers need to consider both the effects of the patient's condition and treatments on her pregnancy and the effects of pregnancy on the disease. The following are key issues of concern for the most common chronic medical conditions encountered in pregnancy.

  • Chronic Hypertension
    • Transition patients to antihypertensives with better safety profiles during pregnancy as many agents, especially angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs), are contraindicated in pregnancy. Recommend antihypertensive medications that may include the following:
      • Labetalol: starting dose of 100 to 200 mg twice daily
      • Nifedipine: starting dose of 30 to 60 mg once daily, extended-release preparation
      • Methyldopa: starting dose of 250 mg 2 or 3 times daily [6]
    • Consider performing studies to assess for evidence of end-organ damage secondary to chronic or poorly controlled disease, including an ophthalmology exam (retinopathy), urine protein testing (renal disease), and electrocardiography (ventricular hypertrophy).
    • Advise patients to avoid smoking and excess sodium and caffeine intake.
    • Monitor patients for pregnancy risks associated with chronic hypertension, including:
      • Preeclampsia
      • Fetal growth restriction [1][6]
  • Pregestational Diabetes
    • Optimize glycemic control (goal HbA1c <6.5%).
    • Address weight management issues.
    • Consider studies to assess patients with long-standing or poorly controlled disease for evidence of end-organ damage (eg, ophthalmology exam, urine protein testing,  or electrocardiography).
    • Screen for thyroid dysfunction, a common comorbidity, if not previously performed.
    • Monitor patients for pregnancy complications associated with  diabetes, including:
      • Congenital anomalies, especially heart defects
      • Fetal growth restriction
      • Neonatal complications, including hypoglycemia, respiratory distress syndrome, and hyperbilirubinemia [1]
  • Hypothyroidism
    • Optimize treatment so thyroid-stimulating hormone (TSH) levels are within normal limits.
    • Monitor patients for pregnancy complications associated with uncontrolled hypothyroidism, including:
      • Early pregnancy loss (miscarriage/spontaneous abortion)
      • Preterm birth
      • Preeclampsia
      • Placental abruption
      • Fetal death [7]
  • HIV infection
    • Optimize antiretroviral therapy (goal of an undetectable viral load).
    • Comanage pregnancy with an HIV specialist.
    • Recommend interventions to reduce the risk of vertical transmission (eg, mode of delivery, compliance with antiretroviral therapy).[8]
  • Thrombophilias
    • Assess the need for thromboprophylaxis during pregnancy; see the table below for ACOG-recommended management guidelines.
      • Low risk for thrombophilia if testing is positive for any of the following: heterozygous factor V Leiden mutations, heterozygous prothrombin G20210A mutations, protein C deficiency, protein S deficiency 
      • High risk for thrombophilia if testing is positive for any of the following: homozygous factor V Leiden mutations, homozygous prothrombin G20210A mutations, heterozygosity for both factor V Leiden and prothrombin G20210A mutations, antithrombin deficiency
    • Consider initiating low molecular weight heparin (LMWH) or unfractionated heparin (UFH) if indicated (see table for indications and regimens). Except in cases of mechanical heart valves, warfarin is contraindicated in pregnancy.[9] 
    • Monitor patients for thromboembolic events due to increased risk during pregnancy.[1][10]

Table 1. Patient History and ACOG Recommended Management

Patient History ACOG Recommended Management[10]
  • Low-risk thrombophilia
  • No prior venous thromboembolism (VTE)
  • Surveillance
  • Low-risk thrombophilia
  • First-degree relative with VTE
  • Surveillance

OR

  • Prophylactic LMWH/UFH
  • Low-risk thrombophilia
  • Single prior VTE
  • No long-term anticoagulation
  • Prophylactic LMWH/UFH

OR

  • Intermediate-dose LMWH/UFH
  • High-risk thrombophilia
  • No prior VTE
  • Prophylactic LMWH/UFH

OR

  • Intermediate-dose LMWH/UFH
  • High-risk thrombophilia
  • Single prior VTE or affected first-degree relative
  • No long-term anticoagulation
  • Prophylactic LMWH/UFH

OR

  • Intermediate-dose LMWH/UFH

OR

  • Adjusted-dose (therapeutic) LMWH/UFH
  • Any thrombophilia with 2 or more VTE
  • On long-term anticoagulation
  • Adjusted-dose (therapeutic) LMWH/UFH

Table 2. Heparin Regimen Options

Regimen Low Molecular Weight Heparin (LMWH) Options Unfractionated Heparin (UFH)
  • Prophylactic dosing
  • Enoxaparin 40 mg SC once daily
  • Dalteparin 5,000 units SC once daily
  • Tinzaparin 4,500 units SC once daily
  • Nadroparin 2,850 units SC once daily
  • 1st trimester: 5,000-7,500 units SC every 12 hours
  • 2nd trimester: 7,500-10,000 units SC every 12 hours
  • 3rd trimester: 10,000 units SC every 12 hours (unless aPTT is elevated)
  • Intermediate-dosing
  • Enoxaparin 40 mg SC every 12 hours
  • Dalteparin 5,000 units SC every 12 hours
  • N/A
  • Adjusted-dose (therapeutic) dosing
  • Enoxaparin 1 mg/kg SC every 12 hours
  • Dalteparin 200 units/kg SC once daily OR 100 units/kg SC every 12 hours
  • Tinzaparin 175 units/kg SC once daily
  • Target anti-Xa levels: 0.6 to 1.0 units/mL 4 hours after the last dose
  • ≥10,000 units SC every 12 hrs to an aPTT target of 1.5 to 2.5 times the control, 6 hours after the last dose

Genetic Disorders and Carrier States

ACOG recommends counseling and offering to test for the following conditions in patients desiring pregnancy:

  • Cystic fibrosis (everyone)
  • Spinal muscular atrophy (everyone)
  • Hemoglobinopathies (everyone, per an ACOG Practice Advisory from August 2022)
  • Fragile X syndrome (anyone with a family history of fragile X-related disorders, including those with premature ovarian insufficiency younger than 40 years and those with intellectual disability suggestive of fragile X syndrome)
  • Canavan disease and Familial dysautonomia (Ashkenazi Jewish descent)
  • Tay-Sachs disease (Ashkenazi Jewish, French-Canadian, or Cajun descent or those with a family history)
  • Other known genetic disorders in the patient or her family (individualized)[1]

Families with histories of genetic disorders should be referred to a genetic counselor to discuss the risks of passing the condition on to their newborns. The genetic counselor can also educate the family on disorders that might impact fertility. 

Additionally, affected patients should be informed that reproductive technologies, such as preimplantation genetic diagnosis before in vitro fertilization, are available options that may reduce the risk of passing abnormal genes to offspring. Referral to a reproductive endocrinology and infertility (REI) specialist is often appropriate for interested couples in these cases.

Immunity and Immunizations

Immunity to rubella, varicella, and hepatitis B should be assessed. Additionally, ACOG recommends updating several other vaccinations before conception (if possible), including the following:

  • Tetanus-diphtheria-acellular pertussis (Tdap): Tdap should also be given at 27 to 36 weeks during each pregnancy.
  • Measles-Mumps-Rubella (MMR): rubella vaccines should be given at least 28 days before conception.
  • Varicella: vaccine should be given at least 28 days before conception. Because this is a 2-dose course, vaccination should begin 2 months before attempting conception.
  • Hepatitis B
  • Meningococcus
  • Pneumococcus (if appropriate)
  • Human papillomavirus (HPV): vaccine should not be delayed while attempting to conceive; if a person becomes pregnant during their HPV series, the series can be paused and resumed after pregnancy.
  • Annual influenza vaccination
  • COVID-19[1]

STI and Cervical Cancer Screening

Patients should be screened for STIs and cervical cancer according to standard guidelines. Based on patient age and other risk factors, consider screening patients for chlamydia, gonorrhea, syphilis, HIV, and hepatitis B and C.

Nutritional Assessment, Folic Acid Supplementation, and Safe Eating in Pregnancy

A healthy diet rich in fruits, vegetables, and whole grains should be encouraged. Additionally, a daily multivitamin is recommended. Patients should also be counseled to avoid excessive vitamin intake during pregnancy, especially with the fat-soluble vitamins A, D, E, and K, levels of which can build up in tissues and become toxic. Excess iodine is also associated with congenital goiter. ACOG has published the eBook "Guidelines for Perinatal Care," which lists specific levels of vitamins and minerals recommended during pregnancy and lactation, as well as guidance on healthy and safe eating during pregnancy.

Adequate folic acid supplementation at conception reduces the risk of a fetus having a neural tube defect (NTD). For individuals at average risk, 400 micrograms daily initiated at least 1 month before conception is recommended. Individuals at higher risk for having a fetus with an NTD include those with a medical history of seizure disorders or NTD, a previous pregnancy with an NTD, or a partner with either a medical history of an NTD or a previous pregnancy affected by an NTD. For pregnancies at higher risk of NTD, 4 mg of folic acid once daily starting 3 months before conception and continued through 12 weeks of gestation is recommended; some studies have shown high-dose supplementation to reduce the risk of NTD by as much as 70%.[11] 

Individuals should also be counseled about safe dietary consumption during pregnancy. Specifically, fish high in mercury content should be avoided. These include larger fish such as shark, king mackerel, marlin, bigeye tuna, swordfish, orange roughy, and tilefish.[12] No more than 2 to 3 servings of low-mercury fish each week is acceptable. Smaller fish with shorter lifespans, such as light canned tuna, tilapia, shrimp, and cod, are low in mercury. All seafood should be fully cooked. Listeria is also a risk during pregnancy, and pregnant women should be counseled to avoid unpasteurized or raw milk, meat spreads, eggs, and meat. Undercooked eggs and meat, which can also be contaminated, should be avoided.[12]

Weight: Obese and Underweight Individuals

Obesity is associated with multiple pregnancy-associated risks, including an increased risk for infertility, early pregnancy loss, gestational diabetes, hypertension, congenital birth defects, fetal macrosomia, cesarean delivery, delivery complications, endometritis, and venous thromboembolic events.[1][13] Additionally, people who are obese have higher risks for chronic diseases outside of pregnancy, such as hypertension, pregestational diabetes, heart disease, and stroke, all of which can lead to additional complications in pregnancy. Women with a BMI greater than 30 should be considered for referral to a dietician.[14]

Women with malnutrition and abnormally low BMIs may be at risk for nutrient deficiencies that increase the risk for low birth weight infants and preterm labor. They should be given dietary counseling and considered for referral to a dietician.

Exercise

Patients should be advised to exercise regularly to improve overall health, reduce cardiovascular risks, and help maintain a healthy weight. ACOG recommends moderate-intensity exercise, at least 30 minutes a day, 5 days per week, before, during, and after pregnancy.[1][15]  Competitive athletes should be counseled to ensure adequate hydration and caloric intake to avoid weight loss immediately before and during pregnancy, which can adversely affect fetal growth and development.[1]

Substance Use and Smoking Cessation

Tobacco use is associated with preterm labor, fetal growth restriction, low birth weight, and placental abruption. Smoking cessation can reduce perinatal mortality and low birth weight by at least 20%. Smoking cessation counseling should be offered to the woman and her partner before and during early pregnancy. Women should be counseled that secondhand smoke can also impact the child's health after birth, including increased risks for asthma and childhood obesity. Healthcare providers can provide structured counseling, for example, using the 5A's intervention, which includes:

  1. Asking about tobacco use
  2. Advising patients quit
  3. Assessing willingness to quit
  4. Assisting patients with quitting through appropriate medications, counseling, referrals, and support groups.
  5. Arrange follow-up and support[1]

Alcohol use in pregnancy is associated with fetal alcohol syndrome, adverse neuropsychological outcomes, and fertility problems.[2][16] Women should be advised to avoid alcohol if they are planning to become pregnant, as experts cannot recommend a safe level of alcohol use.[1] 

Using drugs during pregnancy is associated with neonatal abstinence syndrome, placental abruption (cocaine), low birth weight, maternal morbidities such as hemorrhage and fetal and infant mortality. Women should be advised to discontinue the use of substances and be offered appropriate counseling, support, and treatment to help them achieve their goals. Referral to an addiction specialist is recommended.

Toxin and Environmental Exposures

Preconception assessment of potential exposures in the home environment, community, and occupational hazards is also important to recognize and reduce potential risks during pregnancy, especially during organogenesis. Toxin and environmental exposures may be linked to birth defects, fetal loss, and low fertility. Couples should be encouraged to inquire about potential hazards in the workplace.

Women should be counseled to avoid toxic substances. Toxins with potential impact on reproductive health and neonatal outcomes include lead, arsenic, fluoride, toluene, flame retardants, plastics (eg, bisphenol A [BPA]), pesticides, industrial solvents, formaldehyde, ethylene oxide, phthalates, perfluorochemicals (PFAS), polychlorinated biphenyls (PCBs), and others.[12] Reported adverse associations and suggested counseling are listed below in the table.

Patients should be instructed to clean surfaces using a wet cloth or mop instead of a dry one, as a damp cloth can effectively trap toxic particles, allowing for subsequent removal, whereas a dry cloth may disperse the particles into the air.[12]

Table 3. Toxins, Associated Complications, and Patient Education

Exposure Associated Complications Patient Education[12]
  • Lead
  • Neurodevelopmental delay
  • Decreased cognitive ability
  • Attention deficits
  • Found in buildings built before 1978 (lead paint).
  • Use a wet cloth to clean surfaces.
  • Lead removal before pregnancy.
  • Flame retardants
  • Decrease in motor and cognitive function
  • Decreased cognitive ability
  • Found in foam furniture.
  • Choose products labeled "flame retardant free."
  • Use a wet cloth to clean.
  • Polycyclic aromatic hydrocarbons (PAHs)
  • Preterm birth
  • Low birth weight
  • Autism spectrum disorders
  • They are classified as air pollutants.
  • Follow local air quality alerts and water safety advisories.
  • Avoid outdoor exercise during times of peak air pollution.
  • Solvents
  • Miscarriage
  • Low birth weight
  • Use nontoxic products, which can include vinegar or baking soda.
  •  Phthalates
  • Neurodevelopmental disorders
  • Male reproductive issues
  • Found as a "fragrance" in personal care products and some processed or fast foods.
  • Choose products labeled "fragrance-free" or "phthalate-free."
  • Eat fresh rather than processed foods.
  •  Bisphenol A (BPA)
  • Miscarriage
  • Neurodevelopmental disorders
  • Found in plastics.
  • Choose non-plastic food containers like glass, stainless steel, or ceramic.
  • Per- and poly-fluorinated alkyl substances (PFAS)
  •  Low birth weight
  • Found in nonstick cookware; minimize use as much as possible.
  • Pesticides
  • Childhood cancers
  • Autism spectrum disorders
  • Decreased memory
  • Eat organic as much as possible.
  • Avoid pesticides used at home (eg, bug sprays, bug bombs, and flea baths).

Clinical Significance

During preconception counseling, the clinician should perform a risk assessment, which includes reviewing a thorough history of medical, surgical, psychosocial, genetic, nutritional, and behavioral risks (including screening for alcohol and drug use); appropriate risk-reducing interventions should then be advised. Additionally, education on environmental toxins can be provided, appropriate immunizations recommended, and genetic screening offered. The overall goal is preconception wellness and optimal management of chronic health conditions and behavioral issues. Early preconception counseling and intervention have the potential to significantly reduce perinatal morbidity and mortality, which is the fundamental goal of all obstetric care.[17]

Enhancing Healthcare Team Outcomes

Preconception counseling, risk identification, and intervention require an interprofessional approach and consistent documentation in the healthcare record. The healthcare team should have access to the complete plan of care from the services used by the patient within the system. To improve patient outcomes, every provider should address the potential impact health status can have on pregnancy with all people of reproductive age. In women seeing multiple providers for medical and behavioral care, an interprofessional approach to planning a pregnancy before its conception can be advantageous in identifying and addressing risks.

Nursing, Allied Health, and Interprofessional Team Interventions

Preconception counseling and care are optimized through the collaboration of the following healthcare team members:

Non-obstetric clinicians: Often, medical comorbidities are managed by specialists who do not primarily manage a patient's pregnancy (eg, a neurologist consulted by an obstetrician to manage a pregnant patient's epilepsy). Therefore, careful clinician coordination is essential to ensure optimal care during pregnancy.

Genetic counselors: Detailed advice and education regarding potential genetic risks, screening and testing options, and posttest counseling regarding results and next steps are best provided by genetic counselors who are specially trained in this area.  

Nursing: Nursing team members can provide patient education and prepregnancy counseling. It is, therefore, critical for nurses to know the key aspects of a preconception visit and be able to provide accurate counseling to patients about general health and safety during the preconception period and early pregnancy. 

Pharmacy staff: These team members can be instrumental in identifying medications that may be problematic during pregnancy. Pharmacy staff can encourage patients interested in pregnancy to speak with their providers to ensure they are on the safest (and still efficacious) medications during pregnancy.

Nutritionists/Registered dieticians: These health professionals provide essential care helping over- and under-weight patients achieve healthier weights before pregnancy. This is especially important in patients with other comorbidities, such as diabetes or hypertension.

Addiction specialists, substance use clinics, and tobacco cessation programs: Individuals and support programs such as these play a critical role in helping patients with substance use disorders eliminate or reduce their use. 

Public health/immunization clinic staff: helpful in reducing barriers to health and can provide easier access to appropriate immunizations.

References


[1]

. ACOG Committee Opinion No. 762: Prepregnancy Counseling. Obstetrics and gynecology. 2019 Jan:133(1):e78-e89. doi: 10.1097/AOG.0000000000003013. Epub     [PubMed PMID: 30575679]

Level 3 (low-level) evidence

[2]

Smith A, Barr WB, Bassett-Novoa E, LeFevre N. Maternity Care Update: Preconception Care. FP essentials. 2018 Apr:467():11-16     [PubMed PMID: 29683305]


[3]

Lengyel CS, Ehrlich S, Iams JD, Muglia LJ, DeFranco EA. Effect of Modifiable Risk Factors on Preterm Birth: A Population Based-Cohort. Maternal and child health journal. 2017 Apr:21(4):777-785. doi: 10.1007/s10995-016-2169-8. Epub     [PubMed PMID: 27485494]


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Țarnă M, Cima LN, Panaitescu AM, Martin CS, Sîrbu AE, Barbu CG, Pavel B, Șerbănică AN, Fica S. Preconception Counseling in Patients with Hypothyroidism and/or Thyroid Autoimmunity. Medicina (Kaunas, Lithuania). 2022 Aug 18:58(8):. doi: 10.3390/medicina58081122. Epub 2022 Aug 18     [PubMed PMID: 36013589]


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. Practice Bulletin No. 187: Neural Tube Defects. Obstetrics and gynecology. 2017 Dec:130(6):e279-e290. doi: 10.1097/AOG.0000000000002412. Epub     [PubMed PMID: 29189693]


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American College of Obstetricians and Gynecologists’ Committee on Obstetric Practice. Reducing Prenatal Exposure to Toxic Environmental Agents: ACOG Committee Opinion, Number 832. Obstetrics and gynecology. 2021 Jul 1:138(1):e40-e54. doi: 10.1097/AOG.0000000000004449. Epub     [PubMed PMID: 34259492]

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Sagi-Dain L. Obesity in Pregnancy: ACOG Practice Bulletin, Number 230. Obstetrics and gynecology. 2021 Sep 1:138(3):489. doi: 10.1097/AOG.0000000000004527. Epub     [PubMed PMID: 34412071]


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Martino J, Sebert S, Segura MT, García-Valdés L, Florido J, Padilla MC, Marcos A, Rueda R, McArdle HJ, Budge H, Symonds ME, Campoy C. Maternal Body Weight and Gestational Diabetes Differentially Influence Placental and Pregnancy Outcomes. The Journal of clinical endocrinology and metabolism. 2016 Jan:101(1):59-68. doi: 10.1210/jc.2015-2590. Epub 2015 Oct 29     [PubMed PMID: 26513002]


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Mota P, Bø K. ACOG Committee Opinion No. 804: Physical Activity and Exercise During Pregnancy and the Postpartum Period. Obstetrics and gynecology. 2021 Feb 1:137(2):376. doi: 10.1097/AOG.0000000000004267. Epub     [PubMed PMID: 33481514]

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[16]

Flak AL, Su S, Bertrand J, Denny CH, Kesmodel US, Cogswell ME. The association of mild, moderate, and binge prenatal alcohol exposure and child neuropsychological outcomes: a meta-analysis. Alcoholism, clinical and experimental research. 2014 Jan:38(1):214-26. doi: 10.1111/acer.12214. Epub 2013 Aug 1     [PubMed PMID: 23905882]

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Frayne DJ, Verbiest S, Chelmow D, Clarke H, Dunlop A, Hosmer J, Menard MK, Moos MK, Ramos D, Stuebe A, Zephyrin L. Health Care System Measures to Advance Preconception Wellness: Consensus Recommendations of the Clinical Workgroup of the National Preconception Health and Health Care Initiative. Obstetrics and gynecology. 2016 May:127(5):863-872. doi: 10.1097/AOG.0000000000001379. Epub     [PubMed PMID: 27054935]

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