One of the most important hormones during the early stages of fetal development is human chorionic gonadotropin (HCG). It is primarily produced by the placental cells and its actions are most appreciated during the early weeks of gestation. To know more about hormones visit 1hcgdrops.
Effects on other tissues
The effects of HCG are not limited to the embryo and the uterus. It also affects some of the tissues in the body, such as those that are part of the immune system.
Promotes production of progesterone by the corpus luteum
The corpus luteum is a structure that forms after the mature ovum is released from the ovary. It produces progesterone that helps in preparing the uterus for implantation of the embryo. Progesterone from corpus luteum is crucial in making sure that the embryo continues its normal development while other supportive structures (e.g., placenta, etc) are still in the process of forming.
Fundamentally, the immune system sees any rapidly dividing cell as potentially pathogenic. Rapid cellular division is characteristic of bacteria, yeast and viruses. Trophoblastic cells are rapidly dividing cells that can potentially trigger an immune response. As the trophoblast cells develop, there is a tendency that the immune system would launch an attack against it. An attack would mean a negative effect on pregnancy, which could lead to miscarriage. To prevent this, HCG acts as an immunosuppressant to prevent any damage to the developing embryo.
Promote development of the umbilical cord
The umbilical cord is the vital connection between the fetus and the mother; it is where wastes and nutrients are exchanged, as well as oxygen and carbon dioxide. Without this link, the fetus will likely die. HCG plays a role in the formation of this vital structure.
Effects on the uterus
HCG promotes a supportive environment within the uterus to ensure the proper progression of pregnancy.
Angiogenesis of the uterine vasculature
This refers to the formation of blood vessels within the uterine wall. These new blood vessels are crucial in providing the needed nutrients, oxygen, and other vital substances that will support fetal development.
This is a very important part of pregnancy. The uterus should also expand to accommodate the growing fetus. HCG acts on the uterine muscles to achieve this requirement.
Temporarily inhibits uterine contractions
Uterine contractions are reduced in order to reduce the stress on the developing fetus. As the date of delivery nears, HCG levels also decline, which leads to more frequent uterine contractions. These contractions are important in the latter stages of pregnancy, especially during delivery. Prior to this stage, the uterus should have infrequent contractions because these can cause undue stress to the developing fetus.
Effects on the embryo
HCG also influences the developing embryo. Some of its known effects on embryonic development include:
• Differentiation of the cytotrophoblast
• Promotes growth and differentiation of the different fetal organs
• Helps the blastocyst in sending signals to the endometrium (muscular layer of the uterus) to be prepared for imminent implantation
• Stimulates the enzyme metalloproteinases within the cytotrophoblast cell, which is necessary for successful implantation
Some studies also suggest that HCG also plays an important role in preparing the reproductive tract and the reproductive cells prior to fertilization.
• HCG found in the sperm and in the receptors within the fallopian tubes suggests that there is already communication between these structures that play important roles in fertilization
• HCG receptors are found in the hippocampus, brain stem, and hypothalamus of an adult brain, suggesting a link between vomiting and nausea (common pregnancy symptoms)
A lot of pregnancy tests depend on the detection of this hormone in the blood and in the urine. Aside from acting as a pregnancy indicator, HCG also stimulates and initiates steroidogenesis in the fetal gonads. High levels of this hormone have also been linked to the development of teratogenic effects on the fetus’ gonads.
All in all, HCG is not merely something that indicates pregnancy – it is a hormone that serves a myriad of important roles and could actually determine the outcome of pregnancy.