What are other Names for this Test? (Equivalent Terms)
- Chorionic Somatomammotropin Blood Test
- hPL Blood Test
What is Human Placental Lactogen Blood Test? (Background Information)
- Human placental lactogen (hPL) is a hormone made by the placenta. If the hormone is not made in ample amounts, it may point to a problem with the developing baby
- The human placental lactogen is important in maintaining the nutritional status of the fetus. It helps regulate tissue growth and proper metabolism
- The levels of hPL are detectable 5 weeks into pregnancy. They increase slowly throughout the remainder of the term. A decrease in hPL levels, especially after the 28th week of pregnancy, may indicate a distressed fetus
- The Human Placental Lactogen Blood Test helps determine the levels of hPL in blood. It is used to diagnose fetal distress during pregnancy
What are the Clinical Indications for performing the Human Placental Lactogen Blood Test?
Following are the clinical indications for performing the Human Placental Lactogen Blood Test:
- Following up to an ultrasound or other test(s) indicating a problem with the developing fetus
- Decreased amount of amniotic fluid (oligohydraminos)
- High blood pressure
How is the Specimen Collected for Human Placental Lactogen Blood Test?
Following is the specimen collection process for Human Placental Lactogen Blood Test:
Sample required: Blood
Process of obtaining blood sample in adults:
- A band is wrapped around the arm, 3-4 inches above the collection site (superficial vein that lies within the elbow pit)
- The site is cleaned with 70% alcohol in an outward spiral, away from the zone of needle insertion
- The needle cap is removed and is held in line with the vein, pulling the skin tight
- With a small and quick thrust, the vein is penetrated using the needle
- The required amount of blood sample is collected by pulling the plunger of the syringe out slowly
- The wrap band is removed, gauze is placed on the collection site, and the needle is removed
- The blood is immediately transferred into the blood container, which has the appropriate preservative/clot activator/anti-coagulant
- The syringe and the needle are disposed into the appropriate “sharp container” for safe and hygienic disposal
Preparation required: No special preparation is needed prior to the test.
What is the Significance of the Human Placental Lactogen Blood Test Result?
The interpretation of the value for the Human Placental Lactogen Blood Test depends on the week of gestation.
A high value for the test is interpreted as follows:
- 5-7 weeks - greater than 1.0 mcg/mL
- 8-27 weeks - greater than 4.6 mcg/mL
- 28-31 weeks - greater than 6.0 mcg/mL
- 32-35 weeks - greater than 7.7 mcg/mL
- 36+ weeks - greater than 10.0 mcg/mL
A high level for the test may indicate:
- Diabetes mellitus
- Bronchogenic carcinoma
- Liver tumor
A low value for the test is interpreted as follows:
- 28-31 weeks - less than 2.4 mcg/mL
- 32-35 weeks - less than 33.7 mcg/mL
- 36+ weeks - less than 5.0 mcg/mL
A low value for the test may indicate:
- Fetal distress
- Toxemia of pregnancy
- Threatened abortion
- Trophoblastic neoplastic disease
The laboratory test results are NOT to be interpreted as results of a "stand-alone" test. The test results have to be interpreted after correlating with suitable clinical findings and additional supplemental tests/information. Your healthcare providers will explain the meaning of your tests results, based on the overall clinical scenario.
Additional and Relevant Useful Information:
- Certain factors, such as multiple-birth pregnancies, may interfere with the results of the Human Placental Lactogen Blood Test
Certain medications that you may be currently taking may influence the outcome of the test. Hence, it is important to inform your healthcare provider, the complete list of medications (including any herbal supplements) you are currently taking. This will help the healthcare provider interpret your test results more accurately and avoid unnecessary chances of a misdiagnosis.
The following DoveMed website link is a useful resource for additional information:
Please visit our Laboratory Procedures Center for more physician-approved health information: