Pregnancy Guide

Prenatal Blood Tests — Complete Pregnancy Testing Guide

A trimester-by-trimester guide to the blood tests typically recommended during pregnancy.

Why Prenatal Blood Tests Matter

Prenatal blood tests help monitor your health and your baby's development, screening for conditions that could affect the pregnancy if untreated.

First Trimester Tests

TestPurpose
Blood type & Rh factorIdentifies blood type and Rh compatibility risk
CBCChecks for anaemia and infection
Rubella & Varicella immunityConfirms immunity to these infections
Hepatitis B & C, HIV, SyphilisScreens for infections that can affect the baby
Thyroid (TSH)Untreated thyroid issues can affect pregnancy
First trimester screening (PAPP-A, hCG)Assesses risk of chromosomal conditions

Second Trimester Tests

TestPurpose
Glucose Challenge TestScreens for gestational diabetes (24–28 weeks)
Quad screenAssesses risk of chromosomal and neural tube conditions
CBC (repeat)Monitors for anaemia as pregnancy progresses

Third Trimester Tests

TestPurpose
Group B Strep cultureScreens for bacteria that can affect the baby during delivery (35–37 weeks)
CBCFinal check before delivery
Repeat infection screeningIf risk factors are present
Important: Your prenatal testing schedule may vary based on your individual risk factors and your doctor's recommendations.