Can blood tests be wrong?

Blood tests are extremely accurate but they can be wrong; the test may give an inaccurate result if the test is done too early, as the levels of HCG in the blood may be too low to register on the test. The test may also be wrong if the woman has already suffered a miscarriage, had an ectopic pregnancy or had an abortion as HCG will still be present in the blood even though the woman is not still pregnant.

Higher levels of HCG than normal may indicate:

• A tumour in the placenta
• A multiple pregnancy (twins or triplets)
• Traces of blood or protein in the urine
• Use of medication to ease symptoms of Parkinson’s disease
• Some types of cancer, including ovarian cancer

It may also be possible for the levels to be slightly higher than usual during a normal pregnancy.

Lower levels of HCG than normal may indicate:

• An ectopic pregnancy
• A miscarriage
• A termination

FAQ:

Pregnancy Testing FAQs

• Q1. How soon can I get an accurate result?
• Q2. What happens if the urine test is positive but the blood test is negative?
• Q3. Can blood tests be wrong?
• Q4. What are the common signs of pregnancy?
• Q5. How common are false positive results?
• Q6. When can I do a pregnancy test if I’ve had fertility treatment?
• Q7. How do home pregnancy tests work?
• Q8. Is a blood test more reliable than a home urine test?
• Q9. What does a faint line mean?
• Q10. Why is my period late if I’m not pregnant?

• Q11. Will using contraception alter the result of a fertility test?
• Q12. How do I do a home pregnancy test?
• Q13. How common are false negative results?
• Q14. How soon can I take a pregnancy test after a positive result from an ovulation test?
• Q15. Can I do a pregnancy test before my period is due?
• Q16. What should I do if my test is positive?
• Q17. Do drugs and medication affect pregnancy test results?
• Q18. What should I do if I have pregnancy symptoms but my test was negative?