For many couples who pursue fertility treatments, especially for intrauterine insemination (IUI) or in vitro fertilization (IVF), a common ritual becomes visits for morning monitoring during your treatment cycle. The goals of these sometimes frequent appointments are to make necessary mid-course adjustments to your treatment protocol and to determine the best timing for ovulation or egg retrieval by monitoring estrogen levels and follicle size. This helps us achieve the best possible outcome for you while avoiding potential complications.
Monitoring Prior Starting Your Cycle
There are common initial steps in your fertility journey with Shady Grove Fertility - initial consultation with a physician, meeting with the nurse clinician nurse, initial Day 3 blood work, ultrasound, HSG, and semen analysis. Some of these tests may have been done prior to coming to see a Shady Grove Fertility physician and can be incorporated without repeating.
Once a treatment plan has then been decided upon by your physician, the new protocol begins. This visit is very important because it provides your physician with baseline readings of hormone levels as well as an opportunity to view the uterus and ovaries via ultrasound.
“The ultrasound provides us with a view of the shape and musculature of the uterus, ability to see if there are any cysts present, and a visualization of the uterine lining,” explains Dr. Lorna Timmreck of Shady Grove Fertility’s Columbia office. “Additionally, egg cells should be 'immature' and the follicles at a ‘resting state’.”
Typical baseline blood hormone levels prior to the start of medication for IUI & IVF should be:
- Estrogen – < 50pg/ml
- HCG – < 1 mIu/ml
- Progesterone – < 1ng/ml
Once your physician has reviewed the results of your blood work and ultrasound, you will receive a phone call from your nurse, typically in the afternoon, to confirm your medication protocol and to make an appointment for your next monitoring appointment.
How Much Monitoring Is Needed?
This is a question that is commonly asked by patients when they start their treatment protocol. Since each patient’s treatment cycle is tailored individually for them, so is the amount of monitoring necessary. A patient who is using oral ovulation stimulation medication such as clomiphene citrate (Clomid or Serophene) with an IUI cycle may require only 2 to 3 monitoring sessions, whereas women using injectable medications in conjunction with either an IUI or IVF may need to be seen up to seven times in a two-week period.
“The number of times we bring a patient in for monitoring is correlated by the strength of the medication in their treatment protocol,” said Dr. Robert Stillman. “Patients who are on lower strength stimulation drugs such as Clomid may need to be monitored less frequently. In contrast, patients on stronger, injectable medications need to be watched much closer in order to make adjustments in the amount of medication being given for safety and effectiveness.”
What Does All This Monitoring Mean?
As a treatment cycle progresses, many patients wonder what the ideal follicle size and proper uterine lining thickness needs to be before triggering for IUI or egg retrieval. At each visit, our physicians look for a balance between hormone levels and ovarian response. And since the hormone estrogen is the prime factor in both increasing follicle size and building up the uterine lining, making sure that levels continue to rise throughout the cycle is a key factor.
“I always tell patients ‘you don’t want too much of a good thing’,” explains Dr. Stillman. “We look for the follicles and uterine lining to grow at an appropriate rate. So if we see a patient with too high a response to the medication, then we will adjust it to slow them down some, while we will increase the medication for a patient who may be responding at a slower rate.”
At that first monitoring, the patient’s ovaries should be non-active or “resting” meaning that none of the follicles have begun maturing. As medication is introduced, the follicles will begin to grow, roughly an average of 2 mm per day during the later stages of stimulation. The increase of estrogen levels within the blood provides hormonal evidence that the follicles within the ovaries are maturing.
“The rate of follicular growth is dependant on the phase of the stimulation cycle,” explained Dr. Timmreck. “Early on, follicular growth may be minimal, but once the follicle(s) have committed to ‘active’ growth, then they may grow 1-3 mm per day.”
The number of follicles produced is also dependent on the treatment option. For women who are utilizing an IUI cycle, physicians will look to keep the number of follicles lower to avoid the risks of multiple pregnancy, while in a more controlled IVF cycle a woman may produce a greater number of follicles because we can limit the number of embryos transferred later on “the back end.”
“The expected number of follicles is dependent on many factors, primarily age and overall ovarian reserve,” said Dr. Timmreck. “The definition of a ‘good’ number of follicles varies from patient to patient and is based on their individual treatment protocol and type of stimulation they are undergoing.”
As the follicle grows, the egg within begins maturing. Many patients ask “what is the ideal follicle size” to be able to trigger ovulation.
Dr. Timmreck offers, “The maturity of an egg in the follicle is in part reflected by the follicular size; on average, the ideal follicular size is 18 to 20 millimeters or larger, depending on the type of medications used.”
The increasing estrogen level is also responsible for building the uterine lining. An optimal measurement of thickness for the implantation of a fertilized egg is greater than 7 mm and preferably greater than 8 mm, regardless of the type of treatment one undergoes.
“Besides the thickness, we look for what's called a 'triple-line pattern',” Dr. Timmreck says. “It should look like a pretty feather. That's how we refer to a nice mid-cycle lining that appropriately primed by estrogen.”
When the lead follicle(s) reach about 20mm in size, the estrogen is rising and the uterine lining is a thickened ‘feather pattern’ in a medicated cycle, it is time to administer HCG, or, for some patients undergoing IVF, Lupron. The HCG (or Lupron) brings about the final important phases of maturation of the egg in the follicle, as well as ovulation for an IUI cycle or to plan the proper timing for the egg retrieval in an IVF cycle. It is at this time that the follicle, the estrogen it's producing, and the responding uterine lining should all be working together to create the best environment for the introduction of a fertilized egg.
“By frequently checking the important variables in a fertility treatment cycle through these monitoring visits, we are able to provide the patient with the best chances of achieving their goals of successfully conceiving a healthy pregnancy and ultimately delivering a healthy baby, whether through IUI or IVF” explains Dr. Stillman.