When seeking help for infertility, diagnosis usually begins with a detailed medical history. By asking questions about your medical, surgical, gynecological, and obstetric history, doctors can discover relevant information that may explain or provide a clue as to why you aren’t getting pregnant.
This is followed by a pelvic ultrasound examination that can reveal abnormalities of the uterus, fallopian tubes, or ovaries. The number of resting follicles in the ovary can also be counted using ultrasound to give an indication of the potential response to ovarian stimulation during fertility treatment.
Most couples will have basic fertility testing done before being informed of their chance of success and treatment recommendations. Basic fertility testing usually includes:
- Measurement of the ovarian reserve by measuring follicle-stimulating hormone (FSH) and estradiol levels
- Resting follicle count and anti-mullerian hormone (AMH)
- Basic blood tests to measure hormone levels
- Hysterosalpingogram (HSG) to check the uterus and fallopian tubes
- Semen analysis
These basic tests can be started as soon as you visit a fertility doctor. It’s possible that following these tests, no further testing will be necessary. Pregnancy can be attempted during the diagnostic phase; for example, intrauterine insemination (IUI) can be done in conjunction with clomiphene and can be carried out in the same cycle as a hysterosalpingogram.
Blood Tests to Measure Ovarian Reserve
The body is a delicate balance of chemicals, and blood tests help identify whether there is an imbalance in the endocrine (hormone) system that could be contributing to your infertility. Here are some of the blood tests that may be done:
- Follicle-stimulating hormone (FSH)
- Luteinizing hormone
- Prolactin
- Estrogen
- Vitamin D levels
- Progesterone
- Testosterone
- Thyroxin
- Thyroid-stimulating hormone
Blood tests can be used to assess how many eggs are left in the ovary (also called ovarian reserve). The tests include anti-Müllerian hormone (AMH), Day 3 FSH and estradiol. These are strong predictors of how well your body will respond to fertility drugs. The results of these blood tests, along with the resting follicle count (also called the antral follicle count), are the most conclusive tests of ovarian reserve.
Follicle-Stimulating Hormone (FSH) Levels
A measure of the follicle-stimulating hormone (FSH) level shows how hard your body has to work to stimulate a follicle to grow each month. A high FSH level on Day 3 shows that the pituitary gland in the brain is trying to stimulate an ovary that has a diminished capacity to respond. This is a poor prognostic sign.
Although FSH levels mainly correlate with egg quantity, it should be taken as part of the bigger picture and used in conjunction with other diagnostic factors. The age of the woman is the most overwhelming predictor of success from fertility treatments. A young woman with a high FSH still has a better chance of becoming pregnant than an older woman with normal FSH has. The older woman could have many eggs, but they are more likely to be abnormal because of her age. In the end, quality is what really counts.
FSH levels can predict the chance of a cycle being canceled because of a low response or low egg yield, but age is a better predictor for pregnancy. Ovarian reserve, together with the female partner’s age, are the best predictors of a treatment’s success.
Anti-Müllerian Hormone (AMH) Test
Anti-Müllerian hormone (AMH) is a protein made by cells in small ovarian follicles. Production is highest in the early stages of follicular development when the follicles are smaller than 4 millimeters (less than 1/8 inch) in diameter and stops when the follicle gets bigger. Because only small follicles produce AMH, the circulating blood level can be used as a fairly accurate indicator of how many tiny microscopic follicles are left in the ovary. This is the ovarian reserve.
With increasing age, the ovarian reserve and the amount of AMH produced decline. On the other hand, women with many small follicles (such as those with polycystic ovaries) or a good supply of primary follicles, have a high level of AMH.
Remember, AMH level is not an indicator of egg quality. We do know, however, that the more eggs we retrieve in an IVF cycle, the greater the chance we have to create good quality embryos for transfer. AMH levels may give us an indirect prediction of a woman’s chance to conceive.
One advantage AMH testing has over FSH testing is that the levels are quite constant, and testing can be done on any day of the cycle. No test is perfect, so the results from both the FSH and AMH testing are used in conjunction with other factors when predicting success rates for fertility treatments.
It is important to remember that no test for ovarian reserve can predict your ability to spontaneously conceive. Additionally, a normal test tells you that your ovarian reserve is normal today, it cannot predict what your reserve will look like in one year or three years. The tests simply tell you egg quantity and how well you are likely to respond to fertility treatment.
Hysterosalpingogram for Infertility
A hysterosalpingogram (HSG) is a common test used to determine whether the tubes are (patent) open and if the uterine cavity is normal. A catheter is placed through the cervix into the uterus, and a contrasting dye is injected into the uterine cavity. X-rays are taken of the pelvic area to determine if the dye is traveling through the tubes and spilling into the pelvis, indicating that they are clear and whether there are any uterine abnormalities.
An HSG is part of the basic testing done in the early stages of diagnosis. It’s performed between Days 5 and 11 of the menstrual cycle, and a woman can attempt conception in the same month.
This test is typically performed either by your fertility doctor or by a radiologist in the X-ray department of a hospital or clinic and usually takes 15 to 30 minutes. You may feel some cramping similar to menstrual cramps during the test and for a short time after.
Sonohysterogram for Infertility
A sonohysterogram (also called hysterosonogram or saline-infused sonohysterogram) is similar to an HSG, except it uses ultrasound instead of an X-ray to visualize the uterine cavity. A catheter is used to insert saline into the uterine cavity. Then an ultrasound probe is placed in the vagina. The saline inside the uterus gives the doctor a good view of the inside of the uterus and can be used to diagnose certain types of fibroids and polyps, endometriosis, and other structural abnormalities.
A sonohysterogram is usually carried out at the doctor’s office and takes approximately 5-10 minutes.
Clomid Challenge Test (CCT)
For the clomiphene challenge test (CCT), blood is drawn on Day 3, Day 4, or Day 5 of the menstrual cycle, and the levels of estrogen and FSH are measured. The woman then takes clomiphene citrate tablets (brand name, Clomid) between Days 5 and 9 of the cycle. Blood is drawn around Day 10 of the cycle, and the FSH level is measured once again. The highest level of FSH, whether the Day 3 or the Day 10 level, is used as the test result.
The FSH level following Clomid indicates how well the woman will respond to fertility drugs and her likelihood of conception, depending on age. In general, an FSH level above 10 indicates a lower-than-average success rate. At a level between 12 and 14, the chances of pregnancy are further reduced. And with an FSH above 15, the patient may be advised to consider alternative treatments.
The clomiphene citrate challenge test is not routinely performed as part of the standard fertility workup.
Summary of Basic Fertility Testing
- Egg quality and quantity decline significantly as women age. Both quality and quantity can be average for her age, better than average, or poorer than average in an individual.
- Tests for FSH/AMH indicate ovarian reserve (egg quantity), not the quality of the eggs.
- Younger women are more likely to have a higher percentage of normal eggs, even with low ovarian reserve.
- Older women are more likely to have a higher percentage of abnormal eggs, even with normal ovarian reserve.
- The egg recruited by the ovary each month is random; good-quality eggs are not more likely to grow than poor-quality eggs are.
- The eggs retrieved for IVF are random; good-quality eggs are not more likely to develop than poor-quality eggs are.