By Dr. Sherry LaBeck, ZRT Laboratory
In 2008 ZRT Laboratory introduced the Fertility Profile to assist women in identifying possible hormonal causes of infertility. More recently ZRT launched the Menstrual Cycle Mapping(MCM) test that allows women to map time points throughout their menstrual cycle, measuring levels of estrogen, progesterone and luteinizing hormone (LH).
Since the MCM test was introduced there has been some confusion as to which test is best to evaluate fertility/infertility. The aim of this blog is to clarify the differences between the two tests and when best to use each.
Menstrual Cycle Mapping
The MCM profile measures estrone-3-glucuronide (E1G), pregnanediol-3-glucuronide (PDG) and luteinizing hormone (LH). E1G and PDG are the primary metabolites of estradiol and progesterone excreted in urine. ZRT employs dried urine samples, collected on filter paper, as a more convenient way of measuring these metabolites over several days in a menstrual cycle.
For those women wanting to get pregnant, the MCM profile can provide useful fertility information - answering questions such as:
- Does estrogen rise enough to proliferate a uterine lining for implantation?
- Did ovulation occur during the cycle?
- Is ovulation delayed or different from what is anticipated?
- Did progesterone rise adequately after ovulation?
- Did progesterone drop too early after its peak in the luteal phase?
- Is there a wide LH peak, suggestive of diminished ovarian reserve?
While the MCM profile may provide information about fertility, there are other reasons for selecting this test.
Mapping the rise and fall of menstrual hormones at specific time points within the cycle can assist in solving the mysteries of cyclic symptoms, both physical and mental/emotional. Tracking imbalances of estrogen and progesterone can provide insight for cyclic headaches (migraines), fatigue, bloating, breast tenderness, heart palpitations and hair loss, just to name a few. Being aware of certain hormone changes during the cycle may also explain symptoms of moodiness, irritability, difficulty concentrating, anxiety and depression.
Contraceptive medications suppress natural production of hormones. When the decision is made to discontinue these medications hormones can be imbalanced, attempting to return to a natural cycle. Mapping a menstrual cycle may be helpful in pinpointing where help is needed to get back on track.
Many women are just curious about their menstrual cycles and want to know more about their individual hormonal patterns. MCM can offer a glimpse of their personal physiology.
The Fertility Profile
In contrast, ZRT’s Fertility Profile, provides information about all the sex steroids including estradiol, progesterone and testosterone, but additionally tests markers for other fertility-associated body systems: adrenal, thyroid and pituitary, to identify the myriad of imbalances that can contribute to infertility. This profile tests cortisol’s diurnal rhythm, luteal phase estradiol (E2), progesterone (Pg), testosterone (T), sex hormone binding globulin (SHBG), DHEAS (DS), free T3 (fT3), free T4 (fT4), TSH, TPOab, and early follicular FSH and LH.
Aside from adrenal health, DHEA levels can play a part in improving ovarian reserve (capacity for production of egg cells).
The stress hormone, cortisol is tested via saliva, collected at the traditional times: morning, noon, evening and night, yielding a circadian pattern. Other tests are through dried blood spot with one sample card collected on day 3 of the menstrual cycle for testing FSH and LH and a second card collected in the luteal phase of the cycle, usually day 19, 20, or 21 of a 28 day cycle.
The adrenal hormones, cortisol and DHEA(S), are useful indicators of the hypothalamic-pituitary-adrenal axis (HPA). How a person is affected by stress is often reflected in cortisol and DHEA(S) levels. High, low or fluctuating cortisol levels due to stress can have a direct negative impact on the ovary's production of E2 and Pg and the thyroid’s production of thyroid hormones. Aside from adrenal health, DHEA levels can play a part in improving ovarian reserve (capacity for production of egg cells).
Obviously, estradiol and progesterone levels are important for preparing the uterine lining for implantation and the continued growth of the fertilized egg. Deficiencies of either of these hormones can be problematic. Differing from the MCM Profile, the Fertility Profile looks at only 1 time in the month for these hormones, mid luteal phase. For some, a single E2 & Pg level at the right time of the month can provide important data for ovarian insufficiency and/or luteal phase deficiency. For others, that single time point could miss the bigger picture.
Androgen levels, DHEA(S) and testosterone, can indicate possible problems with insulin resistance or polycystic ovarian syndrome (PCOS) which can result in anovulatory cycles. Since the sex hormones are tested in dried blood spot, the test measures both free and protein-bound hormone levels; SHBG is tested so that free (bioavailable) testosterone levels can also be calculated.
Collected on day 3 of the menstrual cycle, when estradiol is lowest, an FSH and LH level will show if there are enough eggs in reserve and adequate stimulation of those ovarian follicles for optimal fertility. In addition, an imbalance of these pituitary hormones, higher LH than FSH levels, may also indicate a PCOS condition. Elevated FSH values on day 3 will likely be a result of a lower quantity of viable eggs or possible transition to menopause.
Too much or too little thyroid hormone can impact fertility leading to anovulatory cycles, but also problems during pregnancy including miscarriage, poor fetal growth and premature births. Elevated TPO antibodies indicate an autoimmune thyroid disease affecting the ability to conceive and to carry the pregnancy to term.
Which to test?
To conclude, the MCM Profile is more straightforward in the information gathered. Although the data can be useful in helping to assess some causes of infertility, it is also ideal for assessing cyclic symptoms like migraines or bloating. In comparison, the Fertility Profile generates a more diverse and comprehensive interpretation of the fertility picture with which to develop a treatment strategy for women with unexplained infertility.