What does all the bloodwork mean?

Blood tests are done to measure the hormones that play a major role in the woman’s cycle. The following hormones are being measured:

Estradiol (E2)is the estrogen produced by the ovaries in the cells that surround the developing egg. Its main function is to stimulate growth of the endometruim. E2 levels are typically low during menstruation when the endometrium is being shed. They gradually rise during the first 14 days of the menstrual cycle and will peak in the mid-cycle just before ovulation occurs. If no implantation occurs, it will fall eventually to very low levels which contributes to the initiation of the menstrual bleeding.

To assess ovarian reserve, E2 is tested on cycle day 3 together with FSH and LH. An abnormally high E2 levels indicate poor ovarian reserve. E2 is also done to evaluate the development of the egg(s) in the follicle(s). An approximately rising E2 level indicates good progress and agood follicle.  Anti Mullerian Hormone (AMH) is a New Test that can be done anytime in the cycle.

Follicle Stimulation Hormone (FSH) is the hormone released by the pituitary gland, located at the base of the brain. Transported in the bloodstream to the ovaries, FSH stimulates growth and development of eggs. In the normal cycle, just enough FSH is released to stimulate the growth of one egg. In response to FSH, the ovaries produce E2 and other hormones that are released into the bloodstream and are carried back to the pituitary gland where they signal the brain to diminish the release of FSH. This is known as “negative feedback”. In the women with decreased or poor ovarian reserve, the FSH is high and this occurs in menopause.

Luteinizing Hormone (LH) is another hormone that is carried in the bloodstream to the ovaries. There are two main functions of LH in reproduction. The first is the mid-cycle LH surge, the signal to the ovaries to release the developing egg(s). The LH surge is initiated by rapidly rising E2 level, which indicates that the egg is mature and ready for ovulation. The second function of LH is to stimulate the ovaries to produce Progesterone (P4) after ovulation. Mid-cycle testing of LH helps predict when ovulation is imminent.

Progesterone (P4) is an ovarian hormone produced after ovulation. It’s primary function is to mature the endometrium. If no implantation occurs, P4 can also cause the proliferation of the endometrial lining and when the lining gets thick enough menstruation occurs.

Thyriod Stimulating Hormone (TSH), another pituitary hormone, stimulates the thyroid gland to produce thyroid hormones which are essential in normal cell metabolism. If the thyroid gland’s hormone production is insufficient, the pituitary gland releases even more TSH in an effort to stimulate the gland. Therefore, an elevated TSH indicates that insufficient hormone is being produced and the condition is known as ‘Hypothyroidism’. When excess thyroid hormone is being produced, the pituitary gland diminishes the release of TSH. An abnormally low TSH indicates too much hormone is being produced, and the condition is known as ‘Hyperthyroidism’. Either of these two conditions may disrupt reproductive function, resulting in problems with ovulation or spontaneous miscarriage.

Prolactin (PRL), another pituitary hormone, is normally secreted in high amounts following childbirth, as it is necessary to stimulate production and release of breast milk. PRL is also known to interfere with normal ovulation, and because of this effect, it has been referred to as “nature’s contraception.” This is why most women do not ovulate normally while they are breast-feeding. In some women who are not breastfeeding, abnormally high PRL levels are due to the presence of prolactin-secreting pituitary tumor. The tumor is usually benign. In a lot of cases, PRL is also elevated in women who are in a lot of stress (physical or mental). The main effect of an abnormally high PRL is the interference with normal ovulatory function. Therefore, a PRL test is included in the routine testing of the infertility.

Human Chorionic Gonadotropin (hCG) is a hormone produced by the placenta during pregnancy. This is tested to determine whether or not a woman is pregnant. When the blood test is positive, pregnancy is diagnosed. The progress of early pregnancy is often followed by testing hCG after two days for two to three times and weekly until a heartbeat is detected in the ultrasound. A slow rising level may suggest an abnormal pregnancy, such as impending miscarriage or tubal pregnancy. A rapidly rising level is suggestive of multiple pregnancy. Or rare occasions, an extremely high hCG level early in pregnancy is abnormal and is known as ‘molar pregnancy’.