Continuing Education Activity

Antepartum care is the health care provided during pregnancy to optimize outcomes for both the mother and the fetus. The primary objective of the initial antenatal care visit is to establish the estimated delivery date, identify high-risk pregnancies, and perform maternal and fetal screening. During the initial visit, which ideally occurs in the first trimester, prenatal care assessments involve taking a complete medical history, performing physical and gynecological exams, and conducting laboratory and imaging studies. High-risk pregnancies necessitate more frequent surveillance. In addition to initial medical history, the first antepartum visit involves complex clinical assessments, including potential exposures to infections or toxins, and psychosocial assessments to identify issues such as mental health concerns, barriers to care, and exposure to violence and monitoring for potential complications, including baseline metrics (eg, blood pressure, weight, and height), fetal heart activity, and screens for conditions (eg, anemia, infections, and sexually transmitted diseases). This activity for healthcare professionals reviews recommended prenatal screening, fetal surveillance, and patient education, ensuring early identification of high-risk pregnancies, timely antepartum interventions, and improved maternal and fetal outcomes.

Objectives:

• Identify the components of the initial antepartum care visit.
• Implement recommended screening tests during the initial antepartum visit.
• Differentiate low-risk pregnancies from high-risk pregnancies.
• Apply interprofessional team strategies to improve antepartum care coordination and patient outcomes.

Introduction

Antepartum care, or prenatal care, is the health care provided during pregnancy to optimize outcomes for both the mother and the fetus. The primary objective of the initial antenatal care visit is to establish the estimated delivery date, identify high-risk pregnancies, and perform maternal and fetal screening. During the initial visit, which ideally occurs in the first trimester, prenatal care assessments involve taking a complete medical history, performing physical and gynecological exams, and conducting laboratory and imaging studies. High-risk pregnancies necessitate more frequent surveillance. 

Prenatal care has become the most frequently utilized healthcare service within the United States (US), with 98% of women who give birth initiating regular care at some point in their pregnancy.[1] After the first positive pregnancy test, care is typically sought by patients and begins after a confirmed sonographic intrauterine pregnancy. In addition to initial medical history, the first antepartum visit involves complex clinical assessments, including potential exposures to infections or toxins, and psychosocial assessments to identify issues such as mental health concerns, barriers to care, and exposure to violence and monitoring for potential complications, including maternal metrics (eg, blood pressure, weight, and height), fetal heart activity, and screens for maternal-fetal conditions (eg, anemia, infections, and sexually transmitted diseases).[2][3][4]

Ultrasound examinations are essential for accurate gestational dating, detecting multiple pregnancies, and screening for congenital anomalies. Prenatal genetic screening for conditions like aneuploidies and carrier screenings for genetic disorders are also offered. Laboratory tests during prenatal visits confirm pregnancy and screen for conditions such as anemia, infections, and sexually transmitted diseases. Based on individual risk factors, targeted screenings for thyroid function, diabetes, and other conditions are performed. With the increasing focus beginning in the early 1990s on preventing maternal and fetal morbidity and mortality, great efforts have been made to improve access to quality antepartum care for low socioeconomic and minority populations. Although still prevalent despite efforts, the growing disparities between minority populations are rooted in lack of access and complex obstetric and medical risk factors leading to poor obstetric outcomes. Consequently, this approach to antepartum care ensures early identification of potential complications, enabling timely interventions, improved maternal and fetal outcomes, and an enhanced antepartum experience for the patient.[2][3][4]

Function

Initial Prenatal Visit

Ideally, a patient will initiate antepartum care in the first trimester as recommended to facilitate early identification of high-risk pregnancies and genetic screening if elected. However, a great number of women only begin receiving antepartum care after the first trimester for several reasons, including social and health barriers.[5][6] Several elements are involved in the initial antepartum visit, including establishing the baseline maternal-fetal medical condition, proper gestational age and dating, and shared decision-making concerning the intended course of obstetric care. Components of the initial prenatal visit should include a complete medical history, physical exam, pregnancy confirmation, initial prenatal screening tests, genetic screening or diagnostic studies, and anticipatory counseling. Additionally, an obstetrical ultrasound crown-rump length (CRL) assessment at ≤14 weeks gestation is beneficial in accurately calculating fetal gestational age and is recommended if a patient's last menstrual period is unreliable or unknown.[7][8] Most facilities use an electronic or paper obstetrical record to document a summary of these components from each antepartum visit together for easier review.

Clinical history 

Obtaining a complete medical history is critical to identify potential pregnancy complications and help determine the optimal management approach for individual patients.[9] The following should be obtained as part of the clinical history:

• Medical history, including demographic information (eg, occupation, race and ethnicity, marital status), religious or other restrictions (eg, receiving blood products and dietary restrictions), medications, and immunizations
• Obstetrical and gynecologic history, including if the current pregnancy was intended, menstrual regularity, and last menstrual period
• Family history, including genetic conditions and disorders in multiple family members
• Surgical history
• Social history, including recent travel, tobacco use, alcohol and drug use, and histories of sexual trauma or intimate partner violence
• Psychosocial assessments using established screening tools for intimate partner violence (eg, HARK or HITS) [10], substance abuse, depression (eg, Edinburgh Postnatal Depression Scale), and social determinants of health (eg, PRAPARE or THRIVE) [11][12] See StatPearls' companion references, "Postpartum Depression," "Domestic Violence," and "Substance Use in Pregnancy," for more information on these screening tests.

Physical examination

A complete physical examination should also be performed, including complete vital signs, maternal weight, pelvic examination, fundal height, and, depending on the gestational age at presentation, fetal heart rate.[9] The US Preventive Services Task Force (USPSTF) recommends obtaining a baseline blood pressure at the initial visit with reevaluation at each prenatal visit, as this is essential to identify hypertensive disorders in pregnancy. Furthermore, preexisting hypertensive disorders (eg, chronic hypertension) may only be discovered during a prenatal evaluation as the antepartum visit may be the only encounter a young female has had with a health professional. An appropriately sized sphygmomanometer should be used with a larger size cuff in patients with an arm circumference >33 cm. Obtaining an accurate blood pressure measurement is critical. Therefore, clinicians should ensure that patients are relaxed and in a seated position with back support and legs uncrossed while their blood pressure is measured with their arm at the level of the right atrium.[13] A positive screening result for hypertension during pregnancy is a systolic blood pressure of ≥140 mm Hg or diastolic blood pressure of ≥90 mm Hg measured twice at least 4 hours apart in a patient without chronic hypertension.[14] 

Furthermore, maternal body mass index (BMI) should be calculated at the initial prenatal visit as a BMI of ≥30 kg/m² is associated with a higher risk of several pregnancy complications, including fetal death, preeclampsia, gestational diabetes, and preterm birth than patients with a normal BMI.[15] During the pelvic examination, uterine size should be assessed to correlate with the estimated gestational age calculated by the last menstrual period; if an incongruity is noted, further evaluation with ultrasound is indicated.[9]

Pregnancy confirmation

Many women of reproductive age will present for evaluation of various complaints for which pregnancy is the differential diagnosis that should be excluded first, including amenorrhea, abdominal pain, and irregular menses. If pregnancy has not been confirmed by ultrasound imaging before the first visit, a urine or serum beta-human chorionic gonadotropin (β-hCG) should be performed. This hormone comprises dissimilar alpha and beta subunits required for biological activity. β-hCG levels between the serum and urine specimens correlate well but depend on urine-specific gravity. Ideally, a first void is preferred for urine specimens due to increased concentration.[16] However, an elevated β-hCG level is not definitive of a normal or viable pregnancy. Differential diagnoses that may result in elevated β-hCG levels must be considered, including ectopic and heterotopic pregnancy, miscarriage, and gestational trophoblastic disease. Confirmation of a viable intrauterine pregnancy requires ultrasound imaging. Typically, a normal intrauterine pregnancy is visible on transvaginal ultrasound at approximately 5 to 6 weeks gestation. However, in patients with an unknown or unreliable last menstrual period (LMP) or indications for an early ultrasound (eg, vaginal bleeding and pelvic pain), a quantitative serum β-hCG can be used to interpret ultrasound findings. The "discriminatory zone" refers to the quantitative β-hCG value at which a gestational sac should be seen within the endometrial cavity by transvaginal ultrasonography for an intrauterine pregnancy. The parameters for discriminatory zones vary depending on several factors; therefore, its use is debated, but the American College of Obstetricians and Gynecologists (ACOG) generally suggests using a high β-hCG threshold of approximately 3500 mIU/mL to prevent misdiagnosis of a viable intrauterine gestation. Furthermore, in patients with a serum quantitative β-hCG level under the discriminatory zone or clinical features of an abnormal pregnancy, a repeat β-hCG may be performed; an approximate doubling of β-hCG levels in 48 hours is reassuring of a viable pregnancy in the early first trimester. Usually, the β-hCG level will continue to increase in this fashion until 10 weeks gestation, plateauing at approximately 100,000 mIU/mL.[17]

Initial prenatal laboratory studies

ACOG recommends performing a standardized prenatal laboratory panel on every new obstetrical patient at the first visit, including complete blood count (CBC), ABO and RhD type, antibody screen, rubella serology, syphilis serology, hepatitis B serology, and HIV serology (see Table. Recommended Initial Prenatal Serum Laboratory Studies).[9] ACOG and the USPSTF recommend clinicians screen for asymptomatic bacteria with a urine culture to prevent pyelonephritis; USPSTF recommends performing the urine culture at 12 to 16 weeks gestation or at the first prenatal visit, while ACOG only states it should be done at an early visit. However, collecting these laboratory studies simultaneously during the initial prenatal visit is typically easier for the clinician and the patient.[18][19] 

ACOG also recommends targeted evaluation for some conditions in patients with risk factors, including diabetes and thyroid disease, because universal screening for these conditions has not been shown in studies to be as beneficial as those included in standardized prenatal testing. Early testing for type 2 diabetes with a 75-g or 50-g oral glucose tolerance test is recommended by ACOG at the initial prenatal visit in patients who have a BMI of ≥30 kg/m² and 1 of the following risk factors:

• History of gestational diabetes mellitus 
• Hemoglobin A1C ≥5.7% on previous testing
• Immediate family member with diabetes
• High-risk race (eg, African American, Latin American, Native American, Asian American, Pacific Islander)
• Cardiovascular disease history
• Hypertension 
• High-density lipoprotein (HDL) cholesterol level <35 mg/dL or a triglyceride level >250 mg/dL
• Polycystic ovary syndrome
• Physical inactivity [20]

However, recent studies have shown that early screening for gestational diabetes does not prevent adverse outcomes and may even lead to worse outcomes in select patients. Therefore, the effectiveness of the early gestational diabetes screening recommendation is debatable and requires additional studies.[21][22] Additionally, ACOG recommends targeted testing for thyroid disease in patients with the following risk factors:

• Residing in an area of moderate to severe iodine insufficiency
• Hypothyroidism symptoms
• Family of thyroid disease
• History of:

  • Thyroid peroxidase (TPO) antibodies
  • Goiter
  • Age >30 years
  • Type 1 diabetes
  • Head and neck radiation
  • Recurrent miscarriage or preterm delivery
  • Two or more previous pregnancies
  • BMI ≥40 kg/m²
  • Infertility
  • Thyroid surgery or disease
  • Recent administration of iodinated radiologic contrast agents, amiodarone, or lithium [23]

See StatPearls' companion reference, "Thyroid Disease and Pregnancy," for more information on the evaluation and management of thyroid disease during pregnancy. Targeted screening assessment should also be considered for patients with clinical risks of infection, including Zika virus, cytomegalovirus, and tuberculosis.[24][25] Furthermore, a Papanicolaou test, as recommended per current guidelines, and gonorrhea and chlamydia cultures should be obtained during the pelvic examination at the initial visit. Any abnormal results found on antepartum testing should be followed up promptly so as to begin necessary adjustments to prenatal care, repeat laboratory testing, or initiate appropriate referrals.[9] Clinicians should also offer all pregnant patients prenatal screening and diagnostic testing for genetic disorders at the first visit. Thorough counseling on available genetic screening and diagnostic testing options (eg, cell-free DNA, serum-integrated screening, nuchal translucency screening, and chorionic villus sampling) depending on gestational age is critical to ensure patients are able to make informed decisions regarding the pregnancy.[26][27] See StatPearls' companion reference, "Prenatal Genetic Screening," for more information. Depending on the patient's vaccination history, routine vaccinations considered safe during pregnancy, including COVID-19 and inactivated influenza, should be offered also.[28][29] See StatPearls' companion references, "Prevention, Evaluation, and Management of Coronavirus (COVID-19) in Pregnancy and Puerperium," and "Influenza Vaccine," for more detailed information on these vaccines.

Table

Table. Recommended Initial Prenatal Serum Laboratory Studies.

Estimated due date determination and first-trimester ultrasound

Determining an accurate estimated due date (EDD) is a critical component of antepartum care, as most obstetric management varies in relation to a patient's gestational age. According to ACOG, the American Institute of Ultrasound in Medicine, and the Society for Maternal-Fetal Medicine, a first-trimester ultrasound measurement (ie, no more than 13 6/7 weeks gestation) of the fetus is the most accurate modality to confirm an intrauterine pregnancy and determine the estimated gestational age (EGA).[35] The fetal EGA has historically been calculated according to the first day of a patient's LMP instead of a first-trimester ultrasound, which is not always widely available. Due to the limited availability of ultrasound in some regions, the WHO states that 1 ultrasound before 24 weeks is sufficient to assess for fetal abnormalities and confirm dating.[36] ACOG guidelines recommend that the EDD be determined at the initial visit by LMP in patients with a reliable LMP or early ultrasound; however, in pregnant patients with uncertain dating, including individuals with irregular cycles, an uncertain last menstrual period, or a uterine size-gestational age discrepancy, an early ultrasound, preferably in the first trimester, is indicated to determine a more accurate EDD and exclude a multiple gestation.[35][9] Other indications for first-trimester ultrasound include pelvic pain, suspected ectopic pregnancy, vaginal bleeding, suspected trophoblastic disease, nuchal translucency screening, evaluation of pelvic or uterine abnormalities, and chorionic villus sampling guidance.[37][38] See StatPearls' companion reference, "Sonography 1st Trimester Assessment, Protocols, and Interpretation," for more information. 

When ultrasound imaging, preferably transvaginally, is used, the estimated gestational age should be based on the crown-rump length (CRL) measurement, which is accurate within 5 to 7 days up to 13 6/7 weeks gestation. At 14 0/7 weeks gestation and beyond, a CRL measurement is less accurate, therefore, second-trimester fetal biometry should be used at that point to calculate the fetal EGA. See StatPearls' companion reference, "Sonography 2nd Trimester Assessment, Protocols, and Interpretation," for more information. ACOG recommends that 3 separate CRL measurements be obtained and the EDD and EGA be established based on the average CRL measurement. The measurement technique should use a straight line from the fetal cranium to the caudal rump in a midsagittal plane, with a view of the genital tubercle and a longitudinal fetal spine. A gestational sac diameter is not reliable for EDD calculation and is not recommended.[35] Moreover, the accuracy of ultrasound dating varies from 4 to 7 days in the first trimester, 10 to 14 days in the second trimester, and 21 days in the third trimester.[9] Therefore, if the calculated ultrasound EGA before 14 0/7 weeks gestation differs >7 days from the EGA calculated by the LMP, the final EDD should be changed to the dating determined by ultrasound. Additionally, pregnancies with an EDD unconfirmed by an ultrasound examination before 22 0/7 weeks gestational age are considered suboptimally dated, according to ACOG.[35] 

High-Risk Pregnancies

Pregnancies with conditions that increase the risk of antepartum fetal demise are classified as high-risk; in these patients, increased surveillance is indicated.[39] Conditions that determine a pregnancy is high-risk are not well-defined; however, obstetrical history or maternal, fetal, and placental factors can indicate an increased risk of stillbirth, including:

• Fetal indications

  • Fetal growth restriction
  • Multiple gestation
  • Fetal anomalies or aneuploidy
  • Decreased fetal movement
• Maternal indications

  • Diabetes (gestational or preexisting)
  • Systemic lupus erythematous
  • Thyroid disorders
  • Sickle cell disease
  • Renal or liver disease
  • Substance abuse
  • Hypertensive disorders
  • Maternal age older than 35 years
  • Obesity
• Obstetrical indications

  • History of preterm delivery, fetal demise, preeclampsia
  • Placental abruption
  • Postterm pregnancy
• Placental indications

  • Vasa previa
  • Single umbilical cord
  • Polyhydramnios [39]

Maternal-fetal medicine specialists should be consulted in high-risk pregnancies to help determine the best management course for a patient, including the timing and mode of delivery. Additionally, antepartum fetal surveillance, ultrasounds for fetal growth assessment, and optimization of underlying comorbid conditions are some strategies used to help mitigate adverse outcome risks in these patients.[40]

Antepartum Care in the Second and Third Trimester

Following the initial prenatal visit, pregnant patients typically are scheduled to see a clinician every 4 weeks in the second trimester (ie, from 14 to 28 weeks gestation) and more frequently in the third trimester (ie, from 28 weeks to delivery), increasing to every 2 weeks from 28 to 36 weeks gestation, then every week from 36 weeks until birth.[41] The frequency of visits and recommended monitoring increases as pregnancy progresses due to the increased risk of complications and onset of labor as the EDD approaches. Moreover, subsequent antepartum care in the second and third trimesters comprises ongoing assessments, supportive patient education with shared decision-making, and interventions that frequently involve various interprofessional team members. As delivery approaches, the antepartum care in these trimesters is characterized by continued discussions and preparation regarding labor and postpartum issues and delivery expectations. See StatPearls' companion reference, "Antepartum Care in the Second and Third Trimester," for more information.

Issues of Concern

Antepartum Anticipatory Counseling

Patient education and anticipatory counseling are essential components of antepartum care and often comprise a significant portion of each prenatal visit. Appropriate counseling can decrease patient anxiety, create a supportive maternal experience, and reduce adverse outcomes. Therefore, clinicians should thoroughly address general issues (eg, appropriate weight gain, nutrition, and physical activity) as well as individualized concerns that may arise.[42]

Weight gain

Clinicians should initiate discussions regarding weight gain during pregnancy with patients at the first prenatal visit and provide recommendations based on prepregnancy BMI and individual risk factors. Furthermore, continued monitoring of a patient's weight gain is an essential part of antepartum care, as both inadequate and excessive weight gain are associated with pregnancy complications. Poor maternal weight gain is associated with feeding difficulties and low infant birth weight; maternal obesity increases the risk of fetal macrosomia, gestational diabetes, gestational hypertension, preeclampsia, and cesarean section.[43] Furthermore, excessive weight gain has been associated with other adverse outcomes, including low 5-minute Apgar scores, seizures, hypoglycemia, and meconium aspiration syndrome, as well as chronic conditions (eg, childhood obesity, hypertension, and diabetes).[43] Obese pregnant women also have an increased risk of antepartum cardiac dysfunction, proteinuria, nonalcoholic fatty liver disease, and sleep apnea, as well as intrapartum complications, including endometritis, labor induction failure, venous thrombosis, and wound dehiscence. Macrosomia, which has a higher incidence in obese patients, is also associated with maternal complications (eg, protracted or arrest of labor, uterine rupture, genital tract lacerations, and postpartum hemorrhage). Additionally, macrosomic neonates have an increased risk of shoulder dystocia, clavicular fractures, brachial plexus injuries, and nerve palsies. A recent meta-analysis showed the highest risk of adverse outcomes occurred in women with a BMI of >40 and a high total gestational weight gain.[44] The same meta-analysis recommended the following range for gestational weight gain for each prepregnancy weight class:

• Underweight (BMI <18.5): 14 to <16 kg
• Normal weight (BMI 18.5 to 24.9): 10 to <18 kg
• Overweight (BMI 25 to 29.9): 2 to <16 kg
• Obesity grade 1 (BMI 30 to 34.9): 2 to <6 kg
• Obesity grade 2 (BMI 35 to 39.9): weight loss or gain of 0 to <4 kg
• Obesity grade 3 (BMI ≥40): 0 to <6 kg [44]

These gestational weight gain ranges for pregnant patients with obesity grades 1, 2, or 3 were lower than those recommended by the US National Academy of Medicine guidelines, which recommend 5 to 9 kg in this population.[43] Obese patients are more prevalent than underweight patients and continue to increase, with a reported prevalence in the US of approximately 34%.[45] Antepartum weight loss is not recommended due to an associated risk of small for gestational age infants. Therefore, in obese pregnant women, the primary management involves diet and behavioral modifications and increased exercise.[45] However, several studies have suggested that a patient's prepregnancy BMI has a more significant effect on adverse outcomes than the total gestational weight gain.[44] Clinicians performing preconceptual counseling should encourage patients to have a normal BMI before becoming pregnant. For obese patients, the most effective intervention is weight loss before conception.[45] See StatPearls' companion reference, "Preconception Counseling," for additional information. 

Dietary recommendations

In addition to general weight gain, adequate nutritional intake and avoidance of harmful dietary products are essential for a healthy pregnancy. Adequate consumption of calories and nutrients is not only critical for fetal development and maternal physiologic demand but also for the prevention of pregnancy complications and long-term adverse outcomes. Approximately 350 to 450 additional calories above the patient's average daily intake is recommended during pregnancy. Because most women have a diet with inadequate amounts of micronutrients, routine supplementation, and a healthy, balanced diet are recommended. Prenatal vitamins are recommended in all pregnant women to help achieve the recommended amount of micronutrients during pregnancy, including vitamin D, folic acid, iron, calcium, and omega-3 fatty acids (see Table. Recommended Micronutrients in Pregnancy).[62][46][42] However, patients should be counseled on the recommended amount of micronutrients as many prenatal vitamins do not contain the daily amount of recommended micronutrients, and ingestion of several micronutrient sources may lead to overdoses.[47]

Table

Table. Recommended Micronutrients in Pregnancy.

Increased amounts of these micronutrients are necessary to support fetal growth and development and replace subsequent maternal deficiencies secondary to gestational demands. For instance, iron deficiency resulting in first-trimester anemia is associated with preterm delivery and low birth weight, and choline supplementation may improve fetal neurodevelopment, particularly in women with a history of alcohol abuse. Moreover, several studies have demonstrated that certain micronutrients may help prevent preeclampsia.[48] Therefore, clinicians should encourage patients to consume foods that contain these essential nutrients, including fortified cereals, pasta, legumes, bread, cheese, yogurt, salmon, and eggs, ideally before conception.[42] Folic acid supplementation of 400 μg daily is recommended in all pregnant women to prevent neural tube defects; in patients with a high risk for neural tube defects, including those with a family history of neural tube defects, taking antiepileptic drugs, with pregestational diabetes, or with obesity, the optimal dosage for folic acid supplementation is less defined, ranging from 1,000 to 4,000 μg daily.[49] In patients with anemia, additional iron supplementation may be prescribed empirically. Several daily oral iron supplements are available, including ferrous sulfate and ferrous gluconate. Intravenous formulations may be used in select patients (eg, intolerant of oral therapy or severe anemia).[31] Vegetarian and vegan pregnant patients should be advised to supplement nutrients (eg, vitamins B₁₂ and D) primarily found in animal products.[50] Clinicians should also advise patients not to follow any weight-loss diet or fad diet that restricts the consumption of critical nutrients during pregnancy.[48]

Foods that should be avoided or restricted in pregnancy include soft cheeses made from unpasteurized milk, deli meats, sprouts, melons not eaten immediately after cutting, and raw or smoked fish due to potential Listeria monocytogenes contamination. The CDC recommends avoiding all unpasteurized foods during pregnancy to prevent listeriosis.[43] Additionally, fish with a high mercury content (eg, swordfish, shark, orange roughy) and all raw fish should be avoided. ACOG recommends that pregnant patients limit most seafood to 2 or 3 servings a week and consumption of some fish (eg, albacore tuna and Chilean sea bass) to 6 oz a week.[51] Drinks containing caffeine or artificial sweeteners should be limited during pregnancy. Ingestion of >350 mg of caffeine daily (ie, 3.5 cups of coffee) is associated with early pregnancy loss, preterm delivery, and low birth weight; therefore, caffeine should be limited to 200 mg per day during pregnancy. Furthermore, artificial sweeteners have been associated with large for gestational age infants, childhood obesity, and an increased risk of metabolic syndrome later in life.[43] Also, foods containing simple sugars, processed foods, and trans and saturated fats should be limited during pregnancy.[48]

Smoking, alcohol, and illicit drug use 

Although the overall prevalence of cigarette smoking during pregnancy has decreased significantly throughout the US, 7.2% of pregnant women continue to smoke cigarettes. Tobacco use during pregnancy is associated with miscarriage, congenital anomalies, fetal demise, fetal growth restriction, preterm birth, placental abruption, sudden infant death syndrome, and pulmonary dysfunction. Therefore, identifying patients during the course of antepartum care is essential to prevent adverse outcomes. counsel patients extensively regarding risk factors associated with cigarette use during pregnancy, and implement a quitting plan with the identification of foreseeable roadblocks and obstacles to doing so. Behavioral therapy is the preferred method to facilitate tobacco cessation in pregnant patients. Due to the lack of evidence supporting pharmacotherapy or nicotine replacement to assist with cessation attempts during pregnancy, the USPTF stated that the effectiveness in pregnant patients could not be determined.[52]

Like tobacco, alcohol use during pregnancy is associated with adverse effects, including neurological impairment and fetal alcohol spectrum disorder. Fetal alcohol spectrum disorder comprises several abnormalities and functional impairments with varying severity, including growth restriction, notable dysmorphic facial features (eg, short palpebral fissures, smooth philtrum, and thinned vermilion border), and other cardiac, skeletal, renal, auditory, and ophthalmologic dysfunctions. In the US, fetal alcohol spectrum disorder has a reported incidence of 1.1% to 5% but is underdiagnosed.[53] While the exact dose-effect correlation between alcohol use in pregnancy and fetal defects is unknown, several studies show an increased risk among those exposed to excessive binge-drinking behavior. Fetal alcohol spectrum disorder is a well-known complication of excessive fetal alcohol exposure, which is most frequently reported in infants of individuals who ingest >6 drinks a day. However, adverse effects (eg, reduced femur length, decreased birth weight, and colic) have also been reported in women with minimal amounts of alcohol use during pregnancy.[43] Therefore, clinicians should advise patients to completely abstain from alcohol use during pregnancy to prevent alcohol's teratogenic effects. 

Illicit drug use, including prescription opioids during pregnancy, is also of significant concern to both maternal and fetal outcomes. Up to 40% of pregnant women report having used an addictive drug. Adverse effects of substance abuse include teratogenic effects, neonatal abstinence syndrome, developmental impairment, and comorbid conditions such as depression, anxiety, and infectious diseases. Therefore, ACOG recommends universal screening in pregnant patients to decrease the risk of a missed diagnosis.[54] Though marijuana is legal in several states, patients should be advised against use during pregnancy due to increased risks that have been found, including low birth weight and preterm labor.[43] Management of pregnant patients with substance abuse disorders is multifocal, including referral to addiction specialists and rehabilitation programs, infectious disease testing, mental health screening, ultrasound assessment, and antenatal fetal surveillance.[55]

Physical activity

Exercise during pregnancy has several benefits, including decreasing the risk of gestational diabetes, hypertensive disorders, operative deliveries, excessive gestational and postpartum weight gain, and postpartum depression.[56] Patients may have specific concerns regarding exercise safety during pregnancy with an emphasis on promoting healthy lifestyles during antepartum care. ACOG recommends that after thorough clinical evaluation and with no contraindications, pregnant women should be encouraged to participate in regular, moderate-intensity physical activity in sessions of 30 to 45 minutes daily for approximately 150 minutes each week, depending on their starting fitness level. In sedentary patients, physical activity levels should begin with low-intensity exercise and increase gradually.[56] Clinicians should advise patients to gauge exercise intensity by perceived exertion instead of heart rate, which may be affected by pregnancy. Furthermore, patients should be instructed to accommodate exercise for pregnancy by avoiding the supine position since this will put pressure on the vena cava and compromise blood return to the heart, potentially compromising the blood flow to the fetus. Patients should avoid overexertion and dehydration by exercising in a temperature-controlled environment, wearing loose clothing, and remaining well-hydrated.[43]

Exercise activities considered safe in pregnancy include walking, stationary cycling, aerobic dancing, resistance exercises, stretching, swimming, and water aerobics. However, clinicians should counsel patients to be aware of warning signs or symptoms of a potential problem. These warning signs include regular painful contractions, vaginal bleeding, dyspnea on exertion, dizziness, headache, chest pain, or calf pain. If these symptoms should occur, the pregnant patient should stop exercising and consult with her clinician immediately.[56][43]

Relative contraindications to exercise during pregnancy include heavy smoking, poorly controlled disorders (eg, seizure disorder, hyperthyroidism, type 1 diabetes, or hypertension), morbid obesity, malnutrition, intrauterine growth restriction, chronic bronchitis, unevaluated maternal cardiac arrhythmia, history of a severely sedentary lifestyle, symptomatic or severe anemia, and heavy smoking. Absolute contraindications include incompetent cervix or cerclage, multifetal gestations with an increased risk of preterm delivery, persistent vaginal bleeding, preterm labor, placenta previa present after 26 weeks gestation, rupture of membranes, preeclampsia or pregnancy-induced hypertension, significant heart disease, or restrictive lung disease. Activities in which the risk of trauma to the abdomen or falls is increased should be avoided (e.g., skydiving, scuba diving, contact sports, horseback riding, hot yoga, and gymnastics). Heavy weightlifting and long-distance running are also discouraged due to overexertion and dehydration risks.[43]

Travel

ACOG states that pregnant women may safely travel until 36 weeks of gestation, provided there are no complications; however, patients should be advised that when obstetric emergencies occur during travel, they most commonly happen in the first and third trimesters. Modern, adequately pressurized aircraft pose no harm to pregnant patients or fetuses. Patients are advised to ambulate every hour on long flights to prevent thromboembolism and to wear seat belts throughout the flight. Seat belt safety regarding automobile travel should be discussed with all pregnant patients during antepartum care. Specifically, in 3-point restraint seatbelts, the shoulder portion of the strap should be firmly positioned between the breasts, and the lap belt should be safely positioned under the abdomen and across the upper portion of the thigh. Both should be positioned across the body tightly, and airbags should always be present in vehicles and utilized in the event of a high-impact accident.[57][58][59]

Clinical Significance

Antepartum care is the health care provided during pregnancy to optimize outcomes for both the mother and the fetus. The primary objectives are to identify high-risk pregnancies and to monitor the health of the mother and the development of the fetus. Prenatal visits are an intricate balance of maternal and fetal management aimed to prevent significant maternal and fetal morbidity and mortality and provide support throughout the prenatal course. Close follow-up with timely review of new complaints or issues, physical exam findings, sonography abnormalities, and laboratory results facilitate the necessary interventions. These may include escalation of care to more frequent antepartum care visits, close follow-up by maternal-fetal medicine specialists, antepartum fetal surveillance, and potential early delivery depending on the gestational age, clinical picture, and potential improvement of outcomes.

While many interventions can be performed with relative ease, multiple obstacles may prevent the implementation of these recommendations. Clinicians may have racial biases, insufficient knowledge of updated guidelines, or miss diagnoses that lead to suboptimal care. Furthermore, social determinants of health may frequently prevent patient compliance with visits or management recommendations, including reduced access to prenatal facilities, unreliable transportation, communication barriers, childcare needs, and medication costs, resulting in poor patient outcomes. Because of this, clinicians should strive to remain current on all obstetric guidelines, provide supportive, unbiased care, and identify any barriers to antepartum interventions to optimize maternal-fetal outcomes.[2][3][4]

Enhancing Healthcare Team Outcomes

During the antepartum period, obstetric management involves significant challenges due to the complexity of caring for both the patient and the fetus. The dual focus on maternal and fetal well-being necessitates a team-directed approach involving an interprofessional team to enhance patient-centered care, outcomes, patient safety, and team performance. In high-risk pregnancies increased surveillance and consultation with maternal-fetal medicine specialists are critical to managing risks and planning delivery. Antepartum care during the second and third trimesters involves ongoing assessments, supportive patient education with shared decision-making, and coordinated interventions from various interprofessional team members. These professionals conduct regular check-ups, laboratory studies, imaging, and antenatal fetal surveillance to monitor maternal and fetal health, addressing concerns such as fetal movement, maternal blood pressure, and weight gain.

Interprofessional communication is vital, ensuring seamless care coordination and timely response to pregnancy complications, involving collaboration between physicians, nurses, advanced practitioners, nutritionists, and pharmacists to monitor and adjust treatments. High-risk patients may require additional imaging and surveillance, with findings communicated promptly among the team to adjust care plans. Pharmacists play a crucial role in advising on medication safety during pregnancy, while nurses provide patient education and support, reinforcing the care plan and addressing patient concerns. Advanced practitioners often bridge gaps, offering specialized care and guidance on complex cases. By integrating the expertise of all team members and maintaining open lines of communication, clinicians can effectively manage the challenges of antepartum care, ensuring the safety and well-being of both mother and child throughout the pregnancy.

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Disclosure: Shahd Karrar declares no relevant financial relationships with ineligible companies.

Disclosure: Elsa Vadakekut declares no relevant financial relationships with ineligible companies.

Disclosure: Peter Hong declares no relevant financial relationships with ineligible companies.