Measuring early pregnancy loss: laboratory and field methods.

Area of Science:

• Reproductive Endocrinology
• Biochemistry

Background:

• Early pregnancy loss is a significant concern for women attempting conception.
• Detecting very early pregnancy loss requires highly sensitive diagnostic tools.

Purpose of the Study:

• To evaluate the sensitivity and specificity of an immunoradiometric assay (IRMA) for detecting human chorionic gonadotropin (hCG).
• To identify very early pregnancy losses in women actively trying to conceive.

Main Methods:

• 30 women attempting pregnancy collected daily first morning urine samples for up to 6 months.
• Urine samples were tested using an hCG-specific immunoradiometric assay (IRMA) and two radioimmunoassays (RIAs).
• A control group of 5 women with tubal ligations was included.

Main Results:

• The IRMA demonstrated higher sensitivity and specificity compared to RIAs.
• Four cases of early pregnancy loss were identified via hCG rise and fall patterns using the IRMA.
• Three of these four losses were undetectable by RIAs due to low hCG levels.
• No detectable hCG was observed in the control group using the IRMA.

Conclusions:

• The IRMA's enhanced sensitivity and specificity enable the detection of previously undetectable very early pregnancy losses.
• This assay is suitable for epidemiologic studies due to its effectiveness with small urine volumes.