Pregnancy risk assessment

🤰 Pregnancy Risk Assessment is the systematic evaluation of maternal and fetal factors that may increase the risk of complications. ✅ It aims to identify modifiable risks, anticipate problems, and ensure early interventions to optimise outcomes for both mother and baby. ⚠️ High-risk pregnancies require closer surveillance, multidisciplinary input, and sometimes delivery in specialist centres.

🧬 Introduction & Physiology

• Pregnancy involves profound physiological changes — ↑ plasma volume, ↑ cardiac output, hypercoagulability, ↓ functional residual lung capacity.
• These adaptations mean underlying disease may worsen (e.g., cardiac failure, diabetes, asthma).
• Fetal development depends on maternal health, placental function, and uteroplacental circulation. Any disruption can compromise growth or survival.
• Risk assessment balances maternal safety with fetal wellbeing, ideally beginning pre-conception and continuing throughout pregnancy.

1️⃣ Maternal Medical History

• Pre-existing conditions 🫀: Hypertension, diabetes, thyroid disease, renal disease, epilepsy, autoimmune disorders — may worsen or complicate pregnancy.
• Previous pregnancy history 📜: Miscarriage, stillbirth, preterm delivery, preeclampsia, gestational diabetes = ↑ recurrence risk.
• Age ⏳: Teenage pregnancies → ↑ risk of preterm birth & anaemia; maternal age >35 → ↑ risk of aneuploidy, miscarriage, hypertension, GDM.

2️⃣ Lifestyle Factors

• 🚬 Smoking: Associated with placental abruption, IUGR, preterm birth, stillbirth.
• 🍷 Alcohol: Any intake ↑ risk of fetal alcohol spectrum disorder (growth restriction, neurocognitive delay, dysmorphic features).
• 💊 Substance misuse: Cocaine → placental abruption, opioids → neonatal withdrawal, cannabis → low birth weight.
• 🏃 Physical activity: Sedentary lifestyle ↑ risk of GDM; excessive exercise can cause growth restriction if maternal nutrition poor.

3️⃣ Maternal Weight & Nutrition

• ⚖️ Obesity (BMI >30): ↑ risk of GDM, macrosomia, preeclampsia, C-section, thromboembolism.
• 🍽️ Underweight (BMI <18.5): ↑ risk of low birth weight, preterm birth.
• 🥗 Nutritional deficiencies:
  • Folic acid → neural tube defects.
  • Iron → maternal anaemia, preterm delivery.
  • Vitamin D → neonatal hypocalcaemia, rickets.

4️⃣ Obstetric & Gynaecological Factors

• 👶 Multiple pregnancy: Twin/triplet pregnancies → ↑ risk of preterm labour, fetal growth restriction, preeclampsia.
• 🩸 Placental problems: Placenta praevia, accreta, abruption → risk of bleeding, preterm delivery, perinatal mortality.
• ⚠️ Cervical insufficiency: Painless cervical dilatation → miscarriage or preterm labour.
• ⚕️ Uterine anomalies/fibroids: May distort cavity, causing malpresentation or obstructed labour.

5️⃣ Genetic & Family History

• 🧬 Inherited conditions: e.g., cystic fibrosis, thalassaemia, sickle cell, Down syndrome.
• 🧪 Screening:
  • Combined first-trimester screening (nuchal translucency + bloods).
  • Non-invasive prenatal testing (NIPT) for aneuploidy.
  • Carrier screening based on ethnicity/family history.

6️⃣ Infections

• 🧫 TORCH infections: Toxoplasmosis, Rubella, CMV, Herpes → congenital infection risk.
• 💉 HIV, Hepatitis B/C, Syphilis: Universal antenatal screening; vertical transmission preventable with treatment.
• 🦠 Group B Streptococcus: Screen late pregnancy → intrapartum antibiotics prevent neonatal sepsis.

7️⃣ Psychosocial & Environmental Factors

• 🧠 Mental health: Depression, anxiety, bipolar disorder → risk of poor bonding, suicide (leading cause of maternal death in UK).
• 🏠 Support network: Domestic abuse, social isolation, financial hardship → adverse pregnancy outcomes.
• ☢️ Environment: Radiation, toxic chemicals, unsafe work conditions → teratogenic risk.

📊 Summary Table – Pregnancy Risks & Interventions

🔍 Approach to Risk Assessment

• First antenatal booking visit (by 12 weeks): Detailed history, baseline bloods (FBC, group & screen, infections), urine dip, BP, BMI.
• Ongoing monitoring: Growth scans, BP checks, urine protein, glucose tolerance test (if indicated).
• Specialised investigations: Fetal echo (if maternal diabetes/CHD), Dopplers (IUGR risk), amniocentesis (genetic testing).
• Multidisciplinary input: Involvement of obstetric physicians, cardiologists, endocrinologists, mental health teams for high-risk women.

💊 Management Principles

• 🩺 Optimise maternal health: Control BP, optimise diabetes, adjust teratogenic meds (e.g., ACE inhibitors → switch to labetalol).
• 💉 Preventive care: Aspirin in women at high risk of preeclampsia; LMWH in women at high risk of VTE.
• 🍼 Fetal surveillance: Growth scans, cardiotocography (CTG), biophysical profiles in high-risk pregnancies.
• 🏥 Delivery planning: Consider timing, mode, and location of delivery based on maternal/fetal risks (e.g., placenta praevia → C-section in tertiary centre).

📚 Summary

Pregnancy risk assessment is a cornerstone of antenatal care. 👉 It spans medical, obstetric, genetic, lifestyle, and psychosocial domains. 👉 Early identification + tailored management improves survival, reduces complications, and supports maternal wellbeing. 👉 Always think “two patients” – mother and fetus.