What are the next steps for a female patient of childbearing age with a positive pregnancy test in the first trimester?

Initial Management After Positive First Trimester Pregnancy Test

Immediately confirm pregnancy with appropriate testing, perform initial risk assessment, initiate prenatal counseling, and arrange timely referral for ongoing prenatal care. 1

Immediate Confirmation and Assessment

• Confirm the positive pregnancy test and determine the date of last normal menstrual period to estimate gestational age 1
• Perform a focused medical history including reproductive life plan, coexisting medical conditions, current medications, and social support system 1
• If the patient is uncertain about her last menstrual period, a pelvic examination may be necessary to assess gestational age 1
• Rule out ectopic pregnancy in patients presenting with pain, bleeding, history of ectopic pregnancy, history of tubal ligation, or conception with an intrauterine device in place 2

Essential Counseling and Education

• Discuss all available options including continuing pregnancy, adoption, and termination in accordance with patient autonomy 1
• Provide information about normal signs and symptoms of early pregnancy and instruct the patient to report concerning symptoms that may suggest complications 1
• Respect patient confidentiality, especially if the patient chooses not to involve her partner 1

For Patients Continuing Pregnancy

Immediate Interventions

• Initiate prenatal vitamins with folic acid immediately - the usual therapeutic dose is up to 1 mg daily, with a maintenance level of 0.4 mg for adults and 0.8 mg for pregnant women 3
• Review current medications for safety in pregnancy 1
• Advise complete avoidance of alcohol and smoking 1
• Provide guidance to avoid fish with high levels of mercury 1

Critical Screening Tests

• HIV screening should be performed as early as possible during pregnancy to promote informed and timely therapeutic decisions 4
• For women at high risk for HIV (history of STDs, multiple sex partners, injection drug use, sex partners known to be HIV-positive), retest in the third trimester, preferably before 36 weeks' gestation 4
• Hepatitis B surface antigen (HBsAg) screening in the first trimester is strongly recommended 4
• Screen for asymptomatic bacteriuria with urine culture at 12-16 weeks' gestation or at the first prenatal visit if later 1

First Trimester Aneuploidy Screening Options

All women should have the option of invasive diagnostic testing (CVS or amniocentesis) or first trimester screening. 4

First Trimester Combined Screening (11-14 weeks)

• Nuchal translucency (NT) measurement, PAPP-A, and hCG is an acceptable, cost-effective approach for Down syndrome risk screening for women presenting before 14 weeks' gestation 4
• This approach has approximately 70% detection rate with 5% false-positive rate 4
• NT measurement of 3.5 mm or greater warrants detailed anatomic ultrasound and/or echocardiogram, even with low-risk screen result or normal fetal karyotype 4
• Sonographers must be appropriately trained and participate in ongoing quality assurance programs 4

Key Considerations

• Women should be informed of their adjusted risk for Down syndrome and allowed to make decisions based on this number, as individuals weigh risk/benefits differently 4
• Age is no longer used as a cutoff to offer invasive testing 4
• Women who elect first trimester screening and/or CVS should be offered MSAFP screening and/or anatomic survey between 16-20 weeks' gestation for neural tube defect detection 4

Referral and Follow-up

• Make appropriate referrals for prenatal care to an obstetrician or midwife 1
• Expedite and follow through on all referrals, providing a resource listing or directory of providers 1
• For adolescents, consider referral to home visiting and support programs to reduce rates of repeat teen pregnancy 1
• Discuss timing for prenatal care appointments and what to expect 1

Special Population Considerations

High-Risk Hepatitis B Patients

• Pregnant women with HBV DNA levels ≥200,000 IU/ml or HBeAg-positive status should start tenofovir disoproxil fumarate (TDF) at week 24-28 of gestation and continue up to 12 weeks after delivery 4
• Pregnant women with chronic HBV and advanced fibrosis or cirrhosis should receive TDF therapy 4
• Those already on other nucleoside analogues should be switched to TDF 4

Adolescents

• Provide services in a "youth-friendly" manner that is accessible, equitable, acceptable, and appropriate 1
• Encourage adolescents to talk to parents or guardians while maintaining confidentiality 1

Critical Pitfalls to Avoid

• Do not delay referral for prenatal care as this impacts maternal and fetal outcomes 1
• Do not rely solely on clinical examination or home pregnancy tests for diagnosis - laboratory confirmation is essential 5
• Most qualitative pregnancy tests require an additional 11 days past expected menses to detect 100% of pregnancies 1
• Do not overlook the possibility of ectopic pregnancy when symptoms suggest it, as this can lead to severe complications 1
• Do not fail to provide adequate information about all available options, as this compromises patient autonomy 1