How Do Pregnancy Tests Work?
Pregnancy tests detect a hormone called human chorionic gonadotropin (hCG).
Your body begins producing hCG shortly after a fertilized egg implants in the uterus. As early pregnancy progresses, hCG levels rise quickly, often doubling every 48 to 72 hours in the first few weeks.
When hCG reaches a detectable level, a pregnancy test will show a positive result. If levels are still too low, the result may be negative.
What Is hCG and Why Does It Matter?
hCG plays an essential role in early pregnancy. It helps thicken the uterine lining to support a growing embryo, signals the body to stop menstruation, and sustains the pregnancy in its earliest weeks.
The embryo produces hCG first, followed by the placenta, and levels climb steadily through the first trimester before gradually plateauing around week 10.
When Should You Take a Pregnancy Test?
For the most accurate result, it is recommended to test after the first day of a missed period.
Testing earlier can increase the chance of a false negative.
Using first-morning urine can also help, since hCG levels are more concentrated at that time. If you have already taken a test at home and are unsure of the result, coming in for a lab-quality pregnancy test can help you gain more confidence in your next step.
False negatives can happen if testing is done too early. False positives are less common but can happen, for example, after a recent pregnancy or miscarriage, or when certain medications are involved.
Pregnancy Tests at Her Choice Women’s Health
We offer confidential, self-administered pregnancy tests, with support from our nurses. Our team is here to walk you through your results and answer any questions you may have.
If your test is positive, you may be eligible for a limited ultrasound performed by trained medical staff. This can help identify:
- How far along you are and an estimated due date
- The location of the pregnancy
- Cardiac activity and pregnancy development
Reach out to schedule your confidential appointment today.
