Could you tell me how I could find out more about the risks of not
making enough progesterone?  This is said to cause miscarriages.  If
one takes synthetic progesterone, can the problem be solved?

Hi! Thanks for the question.

Before we start, please read the disclaimer below. Take note that the
answer that will be provided here is general information and is not a
substitute for professional medical advice. Please consult a medical
professional before taking any drugs or pursuing any action.

There are two schools of thought as regards to this issue. Some say
that progesterone deficiency does contribute to miscarriages and that
progesterone supplements will be of help. While the other side says
there is still no strong scientific proof for both claims.

The About.com website provides a point of view favorable to
progesterone supplements.

"Progesterone is an important hormone in preventing miscarriage.
Without adequate progesterone, the uterine lining will remain rigid,
thereby, making pregnancy difficult to achieve. The lack of normal
progesterone production by the ovaries in the second half of the
menstrual cycle is called luteal phase defect. Women who have this
defect either are unable to have their fertilized eggs implant in
their uterine lining or, if the egg is implanted, it is so weak that
miscarriage is a certain outcome."

"To lessen the possibility of miscarriage, women who have a luteal
phase defect use progesterone supplements after ovulation to help
maximize the chance of carrying a pregnancy to full term. Progesterone
supplements are also prescribed to women who are undergoing in-vitro
fertilization (IVF) and other methods of assisted reproductive
technology (ART). Progesterone supplements are given to women
following an egg transfer in certain types of fertilization methods.
Treatment for all women using progesterone supplements continues for
at least fourteen days following ovulation."

"Progesterone Supplements"
http://infertility.about.com/library/weekly/aa112898.htm

Our next link meanwhile says that progesterone doesn't cause
miscarriages.

"Progesterone doesn't prevent miscarriages. Miscarriages happen for
many reasons, but lack of progesterone as a cause for miscarriage is
not proven. The low progesterone levels found in pregnancies which go
on to become miscarriages is a sign that the pregnancy is already
failing."

"Inadequate secretion of progesterone during the luteal phase of the
menstrual cycle and in the early weeks of pregnancy has been presumed
to be a causative factor in many cases of recurrent miscarriage."

"A review of pregnancy rates following hormonal treatments for luteal
phase deficiency concluded that the benefits are uncertain, and a
meta-analysis of six trials has reported that exogenous progesterone
supplementation after conception does not improve pregnancy outcome."

"Progesterone for miscarriage"
http://www.womens-health.co.uk/prog.htm

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Easterangel-ga            
Google Answers Researcher

Ob/Gyn's specializing in fertility commonly use Bioidentical
progesterone to prevent 1st trimester miscarriage.  Recent evidence
shows xenoestrogens may prevent the corpus luteum from producing
enough progesterone to maintain the pregnancy.

READ  www.geocities.com/happypregnant

A repeat first trimester miscarriage is almost always a progesterone deficiency.

Synthetic Progestins such as Megestrol and Provera are NEVER USED to
prevent first trimester miscarriage since they cause birth defects.

In a city with a population of 1 million, there may be only 2-4 MD's
that specialize in fertility amoung the OB/GYN's.