The luteal phase is the second half of the menstrual cycle following ovulation. A strong 14-day luteal phase is necessary for successful implantation. Problems with the luteal phase concern not just the egg itself and its production and journey from the ovary through the fallopian tube to the uterus. Luteal phase issues affect the body's "incubator", the production of the endometrial lining of the uterus where a fertilized egg is implanted.


There are several symptomatic indications that may indicate luteal phase defect. If the luteal phase of a woman's cycle is less than twelve days in length, it may indicate a problem. Spotting before menstruation can be another sign of luteal phase defect. Women who are approaching menopause have lower levels of progesterone, thus shortening the luteal phase.

Basal body temperature can also be used as a diagnostic indication. It is generally agreed that progesterone has a hyperthermal effect and raises the basal body temperature at least four-tenths of a degree to one full degree after ovulation. A slow or low rise in body temperature after ovulation might indicate a lack of progesterone production.

Progesterone levels and thus basal temperatures should remain elevated for fourteen days after ovulation. Progesterone levels peak during the middle of the luteal phase, about a week after ovulation. If the corpus luteum is not producing adequate quantities of progesterone, or if the uterine lining is not properly prepared for the role of progesterone, spotting may occur, the basal body temperature may drop, or the period may come early.


Luteal phase defect is termed an ovulatory disorder by Western medicine. Most infertility specialists consider a luteal phase defect an insufficiency of progesterone production. This is certainly a major aspect of this dysfunction-however, if this were the only element to consider, then the administration of exogenous progesterone would cure it. Some studies have demonstrated that there is impaired folliculogenesis (follicle development) in women with luteal phase defect. Other studies have implicated impairment of the levels of FSH or LH as causative. All these factors may play roles in this condition. 


Prior to ovulation, the pituitary gland manufactures and releases luteinizing hormone (LH) which, along with follicle-stimulating hormone (FSH), stimulates the ovaries to produce estrogen and allow the dominant follicle to release a mature egg. Once the egg is released, the dominant follicle collapses. The collapsed follicle becomes a yellow body called a corpus luteum.

The ovary contains two types of cells, granulosa and thecal cells. The luteal phase derives its name from the fact that the luteinized cells from the collapsed follicle undergo a structural transformation, a process known as luteinization. For the luteal phase of the reproductive cycle, the granulosa and thecal cells produce progesterone (the luteinized granulosa cells independent of LH, and the luteinized theca cells in response to LH stimulation). Progesterone prepares the endometrium, or uterine lining, for implantation of the egg after ovulation and fertilization.

Meanwhile, the ovary secretes hormones (inhibin, relaxin, and 17-hydroxyprogesterone) that affect pregnancy, as well as additional hormones that have various reproductive and other functions. During the proliferative phase-the phase of the reproductive cycle preceding ovulation-estrogen levels rise to promote development of the egg within the dominant follicle. At the same time, these higher levels of estrogen cause the endometrium to thicken, ideally to a depth of at least 8 millimeters, and develop progesterone receptors. Progesterone production triggered by the corpus luteum then causes sticky, mucinous substances to be secreted by glands within the uterine lining. Certain proteins appear on the surface of the now-receptive endometrium. These proteins will allow the fertilized egg to adhere to and embed within the uterine lining.

The luteal phase of the reproductive cycle spans from ovulation at mid-cycle until menstruation. The luteal phase should last for at least twelve-to-fourteen days. A luteal phase of less than ten days rarely produces an environment favorable for implantation. If there is a problem with progesterone production-if there is too little, or if it is released too early or too late in the reproductive cycle-or if pregnancy does not occur, LH stimulation decreases, progesterone levels decrease and uterine prostaglandins are released, causing the corpus luteum to shrivel. Because of the lack of progesterone stimulation, the uterine lining is shed and menstruation occurs.

The most important aspect of the luteal phase is the window of implantation. The proteins that appear on the epithelial (surface) cells of the endometrial lining disappear after a certain amount of time. If these factors are not present, or if they pass before the fertilized egg reaches the uterus, implantation will not occur. If implantation does occur, the developing blastocyst burrows into the uterine lining. The embryo will secrete human chorionic gonadotropin which stimulates the ovary to produce more progesterone. This process is called luteal rescue. The corpus luteum must continue to produce progesterone through week 8 or 10 of the pregnancy-otherwise, a woman will miscarry. After week 8 or 10, the placenta is developed enough to take over the primary responsibility for providing progesterone.

Luteal phase defect can also mean that the events signaling endometrial development are out of sync with the rest of the hormonal cycle. For pregnancy to occur, the endometrium must be ready to receive the fertilized egg between four and eight days after ovulation. Any earlier or later than that and even if an egg is fertilized, the blastocyst finds the endometrium unreceptive for implantation and it passes through undetected. If the embryo finds the endometrium receptive to initial implantation, then the mucinous glands, which are necessary for the embryo's continued progress in the uterus, must continue to develop in response to progesterone stimulation. When this process does not precede smoothly, the body's own immune system may be to blame for not allowing the pregnancy to continue.

On the left you can see an endometrium that is not prepared for implantation. The proteins required to accept an embryo are simply not present. On the right you can see a plush uterine lining, ready to accept an embryo in its new home. Even if adequate progesterone has been given to a woman with a luteal phase defect, if her uterine lining is out of sync, the endometrium cannot transform from the A and C states, which show a micrograph and histograph of an unreceptive endometrium, to the B and D states, which show a micrograph and histograph of a receptive endometrium, ready for implantation.


Chinese medicine diagnoses the reason behind the luteal phase insufficiency, not merely the presence of low progesterone, which is a symptom of the problem. Explanations for low progesterone include deficiency in the Kidney energies or Spleen Qi, Blood stasis, Blood or Yin or Essence deficiency, and a condition known as Cold Uterus.


Each of the Chinese medicine diagnoses that correlate to luteal phase defect requires a different kind of treatment to balance the body's energies. This is where correct pattern discrimination can make the difference in treatment outcome. For example, we might recommend that you use natural U.S.P. progesterone cream applied to the skin twice per day after ovulation as recommended by the manufacturer. This doesn't cure the luteal phase defect, though, only addresses its manifestation.

Ultimately, luteal phase defect is a manifestation of an underlying imbalance deep within your reproductive system. When you can identify the root cause, you can apply the appropriate natural treatment and alleviate its manifestation.

When the soil is well prepared, the garden will grow.


This is an actual basal body temperature chart belonging to a patient who had gone through nine years of unsuccessful infertility treatments with a diagnosis of Unexplained Infertility. She wasn't diagnosed with luteal phase defect because her progesterone levels were within normal limits on day 21 of her cycle. However, her period came about two days later. 

Clearly imbalanced, she had a lot of digestive issues which she was told were unrelated to her reproductive problems. Her diet was very poor and she was diagnosed with irritable bowel syndrome. Her TCM diagnosis was a severe Spleen Qi deficiency-she simply was unable to provide enough energy to her reproductive system to support a pregnancy. She began to clean up her diet a little bit, just by eliminating junk foods and coke. She took herbs to improve the Spleen energies and received acupuncture every two weeks. She also did some practice of Qi Gong and meditation. Within three months, she was pregnant naturally. She has had two children since. She also does not have irritable bowel syndrome anymore.