Hormonal tests are an integral element in female fertility testing and assisted reproductive therapies. They are also an important part of the initial examination for couples who have been trying to get pregnant for at least one year, but to no avail. These tests are useful since they help determine causes of infertility, and whether infertility may be due to other health conditions.
Luteinizing hormone – produced by the pituitary gland, this hormone is responsible for regulating a woman’s menstrual cycle and ovulation. Normally it increases rapidly just before ovulation, midway through a menstrual cycle. Testing for luteinizing hormone is usually done to evaluate menstrual problems, such as irregular periods or amenorrhea, or determine the response of a woman’s body to medications prescribed to stimulate ovulation. It is also given to determine whether a woman has undergone menopause.
Follicle-stimulating hormone – also produced by the pituitary gland, follicle-stimulating hormone helps control the menstrual cycle as well as oocyte production by the ovaries. FSH levels vary according to a woman’s menstrual cycle, and peak just before ovulation. The test for FSH helps determine the cause of infertility by ruling out whether the ovaries are functioning properly, and to determine a woman’s supply of oocytes. Testing for this hormone may also be indicated to evaluate menstrual problems, as well as diagnose disorders of the pituitary gland. It can also be indicated to evaluate precocious or delayed puberty in teenage girls.
Estrogen – produced by the ovaries, this hormone actually exists as three types: estradiol, estriol and estrone. Estradiol is most commonly measured in women who are not pregnant, and it varies throughout the menstrual cycle. Estriol is only measured during pregnancy, and can be detected during as early as the first trimester. As such, it can be produced not only by the ovaries, but also the placenta. Estrone is measured in women who have gone through menopause. Indications for testing for estrone also include evaluating tumors of the adrenal glands or ovaries.
Progesterone – produced by the ovaries during ovulation, this hormone functions to prepare the endometrium lining of the uterus for implantation of a fertilized egg. During pregnancy, the placenta also produces progesterone, starting in the latter weeks of the first trimester. Levels of this hormone are tested to determine causes of infertility, to find out whether ovulation is occurring normally, as well as to monitor the function of ovaries and placenta in pregnant women.
Prolactin – produced by the pituitary gland, this hormone is responsible for milk production. Pregnant women can have prolactin levels 20 times as high as their non-pregnant counterparts, and these levels may remain high if they are breastfeeding. Testing for prolactin is indicated for women who suspect that they are infertile, or have abnormal nipple discharge, or to determine the presence of a pituitary gland tumor.
Free T3 – one of two hormones produced by the thyroid gland, T3 is responsible for regulating metabolism in every cell of the body. Low levels of free T3 coincide with low levels of progesterone, which may indicate problems with ovarian function. Testing for not only Free T3, but also the Free T3/Reverse T3 ratio is often recommended for women who have trouble getting pregnant.
DHEA – also known as serum dehydroepiandrostenedione sulfate, DHEA is produced by the adrenal glands, ovaries, as well as the brain. Abnormally high levels of this hormone can be seen in women and girls with polycystic ovarian syndrome, which can cause female infertility.
Androstenedione – produced by the ovaries and brain, levels of this hormone are also measured to determine whether female infertility can be due to polycystic ovarian syndrome.
Pregnancy Test – this test determines the presence of the hormone human chorionic gonadotropin, or hCG. Produced by the placenta, this hormone is present in the woman’s bloodstream as soon as a fertilized egg has implanted in the endometrium layer of the uterus. hCG is also found in the urine, and this explains why urine samples and blood samples can both be used to determine whether pregnancy has been achieved.