Progesterone and Pregnancy
Progesterone has long been called the "pregnancy hormone", and with good reason.
Progesterone is a hormone produced primarily by the corpus luteum of the ovaries and in larger amounts by the placenta when pregnant. It is highly fat-soluble and has been shown to benefit just about every part of the body.
Progesterone is produced most heavily when a woman is pregnant, and secondly, when she is menstruating. In the past, doctors believed that progesterone contributed to severe menstrual symptoms. This is unlikely since, when pregnant, a woman's progesterone levels are 10 to 20 times higher, and similar symptoms do not generally occur. It is much more likely that problems during menstrual cycles are caused by progesterone deficiency.

The understanding of progesterone and its role in the body has catapulted since then. Progesterone has shown indications that not only does it relieve a myriad of symptoms that has long eluded diagnosis, it would seem that it quite effectively aids in fertilization, and helps prevent pre-term deliveries in those women at risk.
There are several factors that can contribute to pre-term delivery, and it is extremely difficult to know if a woman is prone to pre-term delivery, until it happens. Pre-term delivery occurs when uterine contractions start before the 37th week. According to Dr. Carole Mendelson, as published in the July 18th issue of the National Academy of Sciences, progesterone prevents the uterus from contracting throughout most of the pregnancy.
In both women who want to be pregnant, and those that are pregnant, progesterone is your friend. In mid-cycle, after the egg is released, your body starts to produce progesterone that inhibits the effects of estrogen. If the egg is then fertilized, more progesterone is released, otherwise production stops, the uterine wall breaks down, and menstruation occurs. Healthier skin, hair, and muscle tone noticed during pregnancy is also attributed to progesterone.
In the June 12th issue of the New England Journal of Medicine, a published study found that progesterone significantly reduced the pre-term delivery rate of "at risk mothers". It was also noted that the infants were healthier as well. Intestinal necrosis, intraventricular hemorrhage (bleeding in the brain), and the need for oxygen in these infants were significantly reduced.
Natural progesterone is the closest thing to the progesterone produced by the body. In fact, natural progesterone, produced by a several step process involving the Mexican Wild Yam, is bio-identical to the hormone produced by the human body.
To recap, here are some of the reported benefits of natural progesterone related to pregnancy:
According to Dr. John R Lee, the international authority on natural progesterone, many side effects plague the synthetic versions created by the pharmaceutical companies. These synthetic versions are known as: Synthetic progesterone, progestins and Progesterone Acetate. There are no reports of any significant side effects when using natural progesterone.
All reports of natural progesterone causing significant ill side effects, upon further investigation, have been revealed as a synthetic progestin erroneously reported as natural progesterone.
Here is a quote from Dr. Lee about the effects of progesterone: "We know that transdermal progesterone is very affective, very convenient, and very safe. Overdoses do not hurt anybody. They might mess up somebody's period, it could cause the period to change as to when it comes in the month."