What is Placental Lactogen?

The hormone, human placental lactogen, is that is created by the placenta during pregnancy, and is also often referred to as HPL, or human chorionic somatomammotropin. Its main role appears to be converting fat from the mother's diet into energy for the unborn baby. It can cause insulin resistance in the mother, raising the blood sugar levels while ensuring that the unborn baby gets sufficient nutrients. In fact, this type of hormone allows the baby to get the necessary nutrition even when the mother is malnourished.

Human placental lactogen shares some similarities with the human growth hormone since it promotes growth by helping protein tissues form, but it is generally much weaker than the growth hormone. While it often acts similarly to prolactin, which stimulates lactation, it is not known whether placental lactogen has any part in breastfeeding. It is known, however, that its main function is to break down the fat that the mother eats so that the unborn baby always has nutrients available. This process is essential for proper growth, which is why the level of this hormone is supposed to rise as the pregnancy continues, reaching its peak near the end of the third trimester.

The health of a pregnancy may be determined by measuring the amount of placental lactogen present, as the doctor needs to ensure that it is rising gradually so that the unborn baby can grow. This is often figured out by a simple blood test, in which blood is taken from a vein on the hand or elbow. Most women do not need to prepare for this test, though they should be aware that they will likely feel a small pinprick and a slight ache at the site of the blood draw. It should be noted that this test is not considered common, and those uncomfortable with it may talk to their doctor about another method to ensure proper growth.

The level of placental lactogen rises slowly in a normal pregnancy, but there are some valid reasons for a level that is higher than average. For example, women who are pregnant with multiple babies often have a higher level of HPL. Of course, a high level may also indicate medical issues, such as diabetes, Rh incompatibility, a molar pregnancy, or a tumor on the placenta. Pregnant women with low levels of HPL might be experiencing a type of uterine cancer, toxemia, an insufficient placenta, or a molar pregnancy that is aborting itself. While testing for placental lactogen can let the doctor know how the pregnancy is progressing, HCG blood tests and ultrasounds are typically more common methods of making this determination.