Pregnancy test (beta-hCG)

Microbiology

Notes

 

  • The routine pregnancy test has a sensitivity of 25 IU/L
  • The test will become positive 7 - 10 days after conception and by the time of the first missed period levels frequently exceed 100 IU/L
  • A very early pregnancy with low levels of hCG can give a negative result. If pregnancy is suspected a first morning urine sample taken at least 48 hours from the date of this specimen may be of value.
  • hCG levels may remain detectable for several weeks after normal delivery, delivery by caesarian section, spontaneous abortion or therapeutic abortion.
  • A number of conditions other than pregnancy, including trophoblastic disease and certain non-trophoblastic neoplasms cause elevated levels of hCG. Therefore, false positive results are possible.

Sample requirements

Urine

The first urine specimen of the morning is ideal (more dilute urine samples may not contain representative levels of hCG)

30mL sterile Universal

Bottles with boric acid preservative are acceptable

30 mL sterile Universal

Required information

  • Date of LMP
  • History of ectopic pregnancy or loss of established pregnancy

Storage/transport

Store at fridge temperature

Transport as soon as possible at ambient temperature

Turnaround time

1 - 2 days


Page last reviewed: 17/07/2014