Progesterone, an indispensable hormone before and during pregnancy, is produced by the corpus luteum in the ovaries until the eighth week of pregnancy. Later in the pregnancy, the placenta takes over the development of the hormone. Progesterone levels increase rapidly at the time of ovulation and keep on growing until the end of pregnancy. This hormone is essential for the proper development of the uterus and the fetus. Low progesterone levels can cause serious complications and even miscarriage. Some symptoms of low progesterone include bleeding, stomach cramps, back pain, vaginal dryness, insomnia and fatigue.
Implantation
Progesterone prepares the endometrium for implantation and controls endometrial development. In some women, the corpus luteum does not produce enough progesterone, causing the menstrual cycle to be shorter and preventing implantation. Drs. Julia Szekeres-Bartho and Juan Balasch, in their study published in “Human Reproduction," were among the first scientists who showed that luteal phase deficiency might at least partly explain the infertility of some patient groups, such as those with endometriosis. When fertilization occurs among these patient groups, the implantation of the embryo does not happen, because not enough progesterone is in the blood to prepare the uterus lining for the implantation
Abnormal Fetus Development
Adequate progesterone levels ensure proper circulation of blood in the uterus and stimulate the glands of the endometrial wall to secrete uterine fluid that nourishes the embryo. If progesterone levels are low, the blood flow to the fetus drops, causing the fetus to receive insufficient amounts of nourishment. This can even hamper prenatal development.
Contractions and Miscarriage
One of the many ways in which progesterone protects pregnancy is that it prevents the uterine from contracting. If the progesterone levels drop too low, the uterine can start contracting, leading to premature labor and sometimes even miscarriage. Progesterone supplementation has been widely used to prevent miscarriage in patients with insufficient progesterone production, according to Szekeres-Bartho and Balasch.
References
- Colorado State University: Placental Hormones
- National Center for Biotechnology Information: Evaluation of Fetal and Maternal Genetic Variation in the Progesterone Receptor Gene for Contributions to Preterm Birth
- Oxford Journals: Progestagen Therapy for Recurrent Miscarriage
- Human Reproduction: Corpus Luteum Insufficiency and Fertility
