What is the standard protocol for antenatal care?

Standard Antenatal Care Protocol

Standard antenatal care should include a minimum of 8 contacts throughout pregnancy, with the first visit occurring within the first trimester (before 12 weeks gestation), followed by risk-stratified monitoring schedules and comprehensive screening at specific gestational ages. 1, 2

Initial Visit and First Trimester Care (Before 12-16 Weeks)

Preconception and Early Pregnancy Optimization

• Initiate folic acid supplementation (400-800 mg daily) and potassium iodide (150 mg daily) prior to conception or as soon as pregnancy is confirmed 1, 3
• Screen for diabetes, thyroid disease, and sexually transmitted infections at the initial visit 1, 3
• Review all medications for teratogenicity, particularly discontinuing ACE inhibitors, ARBs, and statins (pregnancy category X) before conception 4, 1
• For women with preexisting diabetes, achieve A1C <6.5% before conception to reduce congenital malformations from the 1.4-10.9% range to 1.0-1.7% 4, 1, 3

Risk Stratification for Preeclampsia

Identify women requiring low-dose aspirin (81-150 mg daily) starting before 16 weeks gestation based on the following risk factors 4, 1:

• Major risk factors (any one qualifies): previous preeclampsia, chronic hypertension, pregestational diabetes, BMI ≥35, chronic kidney disease, antiphospholipid syndrome 1
• Minor risk factors (≥2 required): age ≥40 years, first pregnancy, ≥10 years since last pregnancy, family history of preeclampsia (mother/sister), booking diastolic BP ≥80 mmHg, multiple pregnancy 4

Initial Laboratory and Clinical Assessment

• Complete blood count, urinalysis, blood type and screen 3
• Screening for rubella, syphilis, hepatitis B, HIV, gonorrhea, and chlamydia 3
• Physical examination including periodontal, thyroid, heart, breast, and pelvic examinations 3
• Chromosomal/genetic screening based on family history, ethnicity, and maternal age 3

Second Trimester Care (14-28 Weeks)

Monitoring Schedule Based on Risk

For low-risk multiparous women with no preeclampsia risk factors: Follow local protocols per NICE guidelines for low-risk care 4

For women with one preeclampsia risk factor:

• 24-32 weeks: assessments at minimum every 3 weeks 4
• 32 weeks to delivery: assessments at minimum every 2 weeks 4

Essential Second Trimester Interventions

• Perform detailed fetal anatomy ultrasound 1, 2
• For women with pregestational diabetes, schedule fetal echocardiogram 1, 2
• Continue low-dose aspirin for those on preeclampsia prophylaxis 1, 2
• Conduct dilated eye examination for women with preexisting diabetes 1, 3

Third Trimester Care (28 Weeks to Delivery)

Intensified Monitoring After 28 Weeks

• Observe more stringent precautions as serious morbidity from preeclampsia increases, particularly before 32 weeks when placental abruption, HELLP syndrome, and renal failure are more common 4
• Begin antepartum fetal surveillance at 32-34 weeks for high-risk pregnancies, including those with pregestational diabetes 1, 2, 3

Assessment at Every Visit After 20 Weeks

Screen for the following signs and symptoms of preeclampsia 4:

• New hypertension
• New proteinuria (≥+ on more than one occasion or ≥300 mg/24h)
• Headache or visual disturbances
• Epigastric pain or vomiting
• Reduced fetal movements or small-for-gestational-age infant

Delivery Planning

For women with diabetes and good glycemic control without vascular complications: Deliver at 39 0/7 to 39 6/7 weeks 2, 3

For women with diabetes and poor glycemic control, vascular complications, or prior stillbirth: Deliver at 36 0/7 to 38 6/7 weeks 2, 3

Special Populations

Women with Pregestational Diabetes

• Establish multidisciplinary care including endocrinologist, maternal-fetal medicine specialist, registered dietitian, and diabetes educator 1, 3
• Monitor fasting glucose <95 mg/dL and either 1-hour postprandial <140 mg/dL or 2-hour postprandial <120 mg/dL 3
• Perform dilated eye examinations before pregnancy or in first trimester, then every trimester and for 1 year postpartum 1, 3
• Screen for diabetic complications including foot examination, thyroid function, urinary protein, and electrocardiogram 1

Women Requiring Early Specialist Referral

Refer immediately for specialist assessment if women have two or more preeclampsia risk factors, as data show increased risk requiring individualized obstetric planning 4

Critical Pitfalls to Avoid

• Failure to initiate aspirin prophylaxis before 16 weeks in high-risk women, missing the window for preeclampsia prevention 1, 2
• Inadequate preconception counseling for women with chronic conditions, particularly diabetes where preconception care reduces malformations from 1.4-10.9% to 1.0-1.7% 4, 1, 3
• Underestimating the rapid progression of preeclampsia, which can advance to life-threatening situations within 2 weeks of diagnosis, with some requiring delivery within 72 hours 4
• Insufficient patient education about preeclampsia symptoms between scheduled visits, as the condition can develop between assessments 4
• Late first antenatal visit (after 12 weeks), which is associated with eclampsia and fetal death 4

Lifestyle and Nutritional Counseling

• Promote balanced nutrition with "five-a-day" (2 servings fruit, 3 servings vegetables) 3
• Recommend regular moderate exercise appropriate for pregnancy 3
• Counsel on complete avoidance of alcohol, tobacco, and recreational drugs 3
• Provide calcium supplementation (1200 mg daily) if dietary intake is low 1
• Advise on safe food preparation and adequate sleep 3

Mental Health Screening

• Inquire about mental health at every consultation and connect women to relevant resources 2