progesterone pregnancy infertility miscarriage

The Importance of progesterone in pregnancy

Of all female hormones, progesterone (pro-gestation) is the one most essential for conception, and to the survival of the fertilized egg and the fetus throughout gestation.

The levels of progesterone in a woman’s body rise and fall dramatically with her monthly cycles. At ovulation, the production of progesterone rapidly rises from 2-3mg per day to an average of 22mg per day, peaking as high as 30mg per day a week or so after ovulation.

After ten or twelve days, if fertilisation does not occur, ovarian production of progesterone falls significantly. It is this sudden decline in progesterone levels (as well as estrogen levels) that triggers a period, and another menstrual cycle will begin.

If pregnancy occurs, progesterone production increases and the shedding of the lining of the uterus is prevented, preserving the developing embryo.

As pregnancy progresses, progesterone production is taken over by the placenta, and its secretion increases gradually to levels of 300-400mg per day during the third trimester.

During pregnancy, rising progesterone levels prevent the premature shedding of the uterine lining. If progesterone levels drop due to inadequate progesterone production, then a premature delivery could result, or bring about a miscarriage in the early trimesters.

Progesterone also influences the development of the breasts during pregnancy in preparation for producing milk after the birth. It has an impact on ligaments and muscles throughout the body as well, essentially to allow the suppleness and expansion necessary for giving birth. This also accounts for some of the problems which may be experienced during pregnancy – backache, constipation, and low-blood-pressure, for example.

Although the data are not entirely clear, it appears that progesterone may also have an effect on transport time of the ovum in the fallopian tube, and it may make the ovum more susceptible to sperm penetration.

A series of studies conducted more than three decades ago demonstrated that progesterone secretion by the corpus luteum is absolutely required for the success of early pregnancy.


Luteal phase deficiency

Progesterone therapy is recommended for women who have infertility (or habitual miscarriages) secondary to a problem called luteal phase deficiency.

Luteal phase deficiency is a result of inadequate production of progesterone by the ovaries during the second half of the menstrual cycle.

If there is insufficient progesterone during early pregnancy, the embryo may not survive. After this 8-10 week interval, the placenta becomes a major source of progesterone and the ovarian hormones are no longer needed.

It is assumed that if the ovaries cannot make sufficient progesterone during the latter (luteal) phase of the menstrual cycle, then the ovaries would not produce the required levels of progesterone to sustain early pregnancy, resulting in repeat miscarriage.

In women with luteal phase deficiency, it has been customary to extend progesterone treatment into the early weeks of pregnancy to supplement ovarian production of progesterone.

If a woman has had four or five miscarriages in the first six or eight weeks of a pregnancy, this is almost always due to luteal phase failure.

Women can develop luteal phase deficiency after receiving the ovulation medications for In Vitro Fertilization (IVF). Progesterone is therefore prescribed to insure against luteal phase deficiency.


Low progesterone levels linked to ectopic pregnancy

Ectopic means “out of place.” In an ectopic pregnancy, a fertilized egg has implanted outside the uterus. The egg settles in the fallopian tubes in more than 95% of ectopic pregnancies. This is why ectopic pregnancies are commonly called “tubal pregnancies.” The egg can also implant in the ovary, abdomen, or the cervix, so you may see these referred to as cervical or abdominal pregnancies.

None of these areas has as much space or nurturing tissue as a uterus for a pregnancy to develop. As the fetus grows, it will eventually burst the organ that contains it. This can cause severe bleeding and endanger the mother’s life.

A classical ectopic pregnancy does not develop into a live birth.

Low progeserone levels may put you at risk of an ectopic pregnancy.

Low progesterone values are associated with miscarriages and ectopic pregnancies, both considered non-viable pregnancies, and high progesterone concentrations with viable pregnancies.


Here’s what progesterone does

  • Helps to regulate the menstrual cycle
  • Prepares the lining of the uterus for implantation
  • Keeps the lining of the uterus thick which is necessary for a successful pregnancy
  • Produces a rise in temperature after ovulation, which remains until menstruation occurs
  • Creates a nutrient rich environment for the baby by increasing glycogen and arterial blood to the lining of the uterus
  • Keeps the uterus from having contractions
  • Causes the cervix to thicken and create a mucous plug which prevents bacteria from entering the uterus

Therefore, since bioidnetical progesterone has been found to reduce the incidence of birth defects and complications in pregnancy, it would seem reasonable to be sure that your own progesterone has returned to normal before getting pregnant. Then, once you have confirmed you are pregnant, consider adding supplemental progesterone (cream/lotion) to top up your own levels until at least mid-way through your pregnancy when, during the second and third trimesters of pregnancy, the placenta takes over the production of progesterone.


Symptoms of low progesterone levels

Though there are many symptoms that can help you identify whether or not the progesterone levels in your body are low, however, the most common symptoms include:

  • Depression
  • Appetite Changes
  • Anxiety
  • Weight Changes
  • Irritability
  • Headaches
  • Low Libido drive
  • Painful intercourse
  • Lack of concentration
  • Insomnia
  • POCS
  • Thyroid dysfunction
  • Breast tenderness
  • Fibrocystic breasts
  • Irregular menstruation


Will over-the-counter progesterone cream work?

Absolutely, yes yes yes!

The GOOD NEWS is that the usage of clinical strength bioidentical progesterone cream can help elevate progesterone levels in the body to normal and facilitate the preparation of the uterine lining for pregnancy.

As I write this article, I’m coaching a young trained Midwifery Nurse through her second pregnancy. ‘Sarah’ had just about given up all hope of being a mother again following repeat miscarriages coupled with a profound sense of loss and frustration given the field she works in. The missing piece to the puzzle was to get her progesterone levels back to ‘normal’ before trying for another baby, and to support her ovarian production of progesterone in those first 7-12 weeks of pregnancy by dabbing on a quality, organic progesterone cream twice a day.

Sarah used, as her guide, my self-help ebook ‘Progesterone & Pregnancy’ to step her through how to use progesterone supplementation to trigger ovulation and, once conception is confirmed, continue daily usage until at least half-way through the second trimester. I’m thrilled to report Sarah looks amazing, now well into her pregnancy, and so ready to be a mum again!

Fifteen years supporting & advocating for women’s choice of bioidentical hormones while guiding my two daughters and women like Sarah and Kimberley through successful pregnancies using bioidentical progesterone, I feel it’s so vital we capture our success and share the knowledge of what we are learning on this journey. Because progesterone is not talked about in medical circles (outside of IVF) and is thus “hidden” from the very women who are screaming out for more knowledge on this very PERSONAL subject.

Mums-To-Be, just make sure you select a premium progesterone cream that is all natural, and is free of harmful chemical additives or artificial preservatives.


Where to get guidance and support

For guiance around choosing a premium cream that’s right for you, Click HERE.

To learn using our Articles Library how supplemental bio-identical progesterone can help improve fertility and protect both mother and child against complications during pregnancy, Click HERE.

For women struggling with infertility or repeat miscarriages, my e-Book ‘PROGESTERONE & PREGNANCY: A Guide to Using Bioidentical Progesterone to Facilitate Fertility and Support Pregnancy’ is a MUST READ! This e-Book is a comprehensive guide covering all that you need to know to understand the vital connection between progesterone and pregnancy. I have compiled this e-Book on tried and tested suggestions reported by women who’ve successfully incorporated supplements of bio-identical progesterone to increase their chances of pregnancy and protect the mother and child against complications during pregnancy. Click HERE to download your ebook

In love & gratitude,

Catherine P. Rollins
Founder & CEO
Ethically Supporting Women’s Choice of BHRT Since 2001


Further Reading

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