Human Placental Lactogen

What is human placental lactogen?

Human placental lactogen is a hormone released by the placenta when a person is pregnant.

The placenta is a temporary organ that develops in your uterus during pregnancy. It attaches to the wall of your uterus and provides the fetus with oxygen and nutrients. It also removes waste from fetal blood.

Healthcare providers may measure human placental lactogen with a blood test. The results can help determine whether the placenta works well and the fetus is healthy.

What is another term for human placental lactogen?

Human placental lactogen is also called human chorionic somatomammotropin (HCS).

What is human placental lactogen’s function?

Scientists don’t fully understand all of the roles of human placental lactogen. They believe it stimulates the milk glands to prepare your body for breastfeeding.

They also believe it regulates metabolism, so your blood has more nutrients for the fetus. Human placental lactogen also may help your body be less sensitive to insulin. Insulin is a hormone that moves glucose (sugar) from your bloodstream into your cells. Decreased insulin sensitivity helps more glucose stay in your bloodstream for use by the developing fetus.

What’s a normal human placental lactogen level?

Throughout fetal development, human placental lactogen levels increase:

• In a person who’s not pregnant, the level is 0.00-0.10 mcg/mL (micrograms per milliliter).
• In the first trimester, the level reaches 0.20-2.10 mcg/mL.
• In the second trimester, the level reaches 0.50-6.70 mcg/mL.
• In the third trimester, the level reaches 4.50-12.80 mcg/mL.
• After pregnancy, the levels return to normal.

A blood test can detect human placental lactogen around the sixth week of pregnancy. Levels are usually higher in people expecting twins or triplets.

How do you measure human chorionic somatomammotropin?

A healthcare provider may want to test this hormone if:

• The level of amniotic fluid (liquid surrounding the fetus) is low.
• They detected something unusual during a prenatal ultrasound.
• You have high blood pressure (hypertension) during pregnancy.
• You’re at risk for gestational diabetes.

A simple blood test measures human placental lactogen. A healthcare provider inserts a needle into a vein in your arm and collects a small tube of blood for testing.

What does a high human placental lactogen level mean?

If you have an unexpected level of human placental lactogen, your healthcare provider will explain the results. They’ll take into account many other factors and may order additional tests. A high level could be an indication of diabetes or multiple fetuses.

What does a low level mean?

A low level of human placental lactogen might mean:

• Miscarriage.
• Preeclampsia.
• Problems with the placenta or fetal growth.

What can I do to have a normal human placental lactogen level?

You can’t control your hormone levels during pregnancy. But certain strategies before and during pregnancy can help you prevent gestational diabetes and high blood pressure.

• Avoid junk foods and foods and drinks that are high in sugar.
• Choose healthy proteins, carbohydrates and fats (for example, olive oil rather than fried foods).
• Eat plenty of fruits and vegetables.
• Exercise regularly.
• Maintain a healthy weight.

What else can I ask my doctor about human placental lactogen?

If your healthcare provider orders a human placental lactogen blood test, consider asking the following questions:

• Why did you order this test?
• Do I need to prepare for the test, such as fasting beforehand?
• When will I get the results?
• If my human placental lactogen levels are low, why?
• If my human placental lactogen levels are high, why?
• Am I at risk for gestational diabetes or high blood pressure?
• What other hormones did the blood test measure, and what do those results mean?
• Should I have any other tests, such as an ultrasound?

A note from Cleveland Clinic

Human placental lactogen is a hormone released by the placenta when a person is pregnant. A simple blood test can measure the hormone. Results can help determine the health of the placenta, fetus and pregnant person. If your healthcare provider orders a hormone test, ask why and what the results mean for you.