What is a Luteal Phase Defect?

Defining LPD and what you can do about it…

Related Article: Learn about Progesterone

Any medical terminology or phrase with the word “defect” attached to it certainly exudes a frightening tone. However, a luteal phase defect might be better translated as a simple “shortcoming” in the ability of the body to produce sufficient amounts of progesterone during the luteal phase of the menstrual cycle. Moreover, this shortcoming is in most cases treatable through either medical, dietary, and/or naturopathic means.To understand what a luteal phase defect is, we must first define the luteal phase and the role of progesterone in regulating the menstrual cycle and maintaining a pregnancy. The luteal phase is simply the second half of the menstrual cycle – the two-week period spanning from ovulation to menstruation. It’s called the luteal phase due to the fact that, following ovulation, the corpus luteum begins producing the hormone progesterone. (While estrogen is dominant during the first half the cycle, progesterone governs the second half, or luteal phase.) The corpus luteum only comes into being after the egg is released. In fact, a corpus luteum is nothing other than the ovarian follicle – but transformed into another role following ovulation.

Progesterone performs a number of reproductive functions: Among, these, it warms the body. It builds the uterine lining for implantation of a fertilized egg. In the case of pregnancy, it prevents menstruation – thus you experience a missed period. When a woman becomes pregnant, progesterone levels should remain high and the menstrual cycle will be placed on “hold”.

BBT Chart Example
In this image, the luteal phase corresponds with the increase in body temperature associated with ovulation and the production of progesterone by the corpus luteum. This image represents and idealized 28-day cycle with normal luteal/progesterone functioning. BBT Charting can help you identify a luteal phase defect. Also see: What Can BBT Charting Tell Me?

For most women, the luteal phase will last about fourteen days, though it can span anywhere from ten to seventeen days and still be considered “normal”. A luteal phase defect is typically associated with a shortened luteal phase of around ten days or less (though there is some debate as to what defines a luteal problem or shortened phase). In most cases, a luteal phase defect is attributable to low progesterone levels or insufficient/unsustained progesterone production by the corpus luteum.

With the decrease of progesterone, the uterine lining begins to break down (or will not develop properly in the first place) and menstruation takes place. For women who exhibit symptoms of luteal phase defect, menstruation simply takes place sooner than it should (and the cycle phases will not be in balance). Also, the uterine lining may not “build” to a healthy point where implantation of a fertilized egg can take place. However, in the event a pregnancy is achieved, LPD may also initiate menstrual bleeding and cause an early miscarriage.

The causes of luteal phase defect can be traced to a few principle factors. First off, a luteal phase problem may have its root in the first half of the cycle. That is to say, for the corpus luteum to function properly, it must develop and fully mature in its earlier incarnation as an “ovarian follicle”. Maturation of the ovarian follicle requires adequate follicular development brought about by another reproductive hormone – follicle stimulating hormone, or FSH. Low levels of FSH (or stress on the ovarian follicle) can prevent its full maturation; thus, during the luteal phase, this may lead to a corpus luteum that is unable to perform its proper function in producing progesterone at adequate or sustained levels. However, failure of the corpus luteum may also occur even in the case of a healthy, fully-developed follicle. In either situation, the corpus luteum prematurely falters or fails to deliver adequate levels of progesterone.

Here’s where bbt charting comes in. If you are bbt charting, you’ll be able to identify a short luteal phase (as well as cycle irregularity or ovulation problems). If you suspect that you have a luteal phase defect, you can then discuss your chart with your doctor and s/he can suggest treatments or pursue further testing.

As luteal phase defect may be the result of hormonal imbalances, your doctor or naturopath may suggest any number of remedies, from vitamin and fertility supplements (containing the herb, vitex agnus castus) to acupuncture. Supplements like FertilAid contain vitex and are designed to help support cycle balance and regularity. Also, natural progesterone creams may also prove beneficial in supporting the luteal phase of your cycle. Your doctor may also suggest prescription medications as well. In any case, the important thing to remember is that luteal phase defect can be corrected in most situations. And if you are trying-to-conceive, consider fertility charting as not just a means to predict ovulation, but as a general tactic for learning about your body’s stages and phases.

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