Question 19. What are Natural Cycle fertility treatments and am I a candidate for them?

Given the interest in organic food, environmentally friendly energy and "green" buildings, I guess it was only a matter of time until Natural Cycle fertility treatments became more attractive to all of us. Remember those Promise margarine commercials that would end with "It's not nice to fool Mother Nature!" Well, sometimes Mother Nature may in fact know best and that is the idea behind Natural Cycle fertility treatments.

I think that one has to be creative when considering the infertile couple and using Natural Cycles for fertility treatment may make a great deal of sense for a variety of patients. So without further delay, here is the Question of the Day for the upcoming 2nd Edition of 100 Questions and Answers about Infertility:


19. What are Natural Cycle fertility treatments and am I a candidate for them?

Natural Cycle Fertility treatments are based entirely on a woman’s normal natural menstrual cycle. In other words, no ovarian stimulating drugs are used. Rather, the doctor attempts to produce pregnancy using the woman’s naturally produced egg and/or hormones. In order to use any form of Natural Fertility treatment, the patient must have fairly regular menstrual cycles. Highly irregular cycles do not allow the use of natural fertility treatment. Three different types of Natural Fertility treatments currently exist and they are Natural Cycle IUI, Natural Cycle IVF, and Natural Cycle FET.


Natural Cycle IUI

Natural Cycle IUI is an extremely simple infertility treatment. Generally speaking, the patient is monitored during a menstrual cycle to determine the timing of ovulation using either urine LH, blood estradiol and progesterone or sonography. Once the egg has been determined to be mature ovulation can be induced by a single injection of human chorionic gonadotropin (hCG) followed by a well timed artificial insemination(IUI). Sometimes IUI is performed without the use of hCG if it appears that an LH surge has already begun based upon hormone testing. See Question xxx for more information about IUI.

Natural Cycle IVF (NC-IVF)

Natural Cycle IVF (NC-IVF) also requires that the patient have fairly regular normal menstrual cycles. NC-IVF is a very simple, patient friendly form of IVF. No ovarian stimulating drugs are used in NC-IVF. Instead , the patient’s naturally produced follicle and egg are monitored using estradiol, progesterone and ultrasound measurements. Once the egg is judged to be mature, a single injection of hCG is given and the egg easily collected in the office under transvaginal ultrasound using minimal or no sedation. It literally takes only a few minutes to collect the egg, similar to a simple in office blood draw. The egg is then fertilized usually by ICSI (as only one egg is obtained) and a single embryo is transferred 3 or 5 days later. Couples with proven previous fertility may use IVF without ICSI in many cases.

NC-IVF is extensively performed around the world in over 50 countries and the world’s very first successful IVF baby in 1978 was produced using NC-IVF. At that time, our knowledge and technology was rudimentary compared with today’s standards, so fertility drugs were used to obtain more eggs and embryos to improve the very low IVF pregnancy rates. With improved understanding and technology, many eggs and embryos are simply not necessary to produce a successful pregnancy for many couples using IVF. Also the costs for NC-IVF are about 20-25% of the cost of a single stimulated IVF cycle and NC-IVF avoids the risks associated with the use of ovarian stimulating hormones. Thus, patients who are planning on a single embryo transfer or who wish to avoid using fertility drugs often prefer NC-IVF. Other patients who fail stimulated IVF or who wish to try NC-IVF with their own egg prior to considering ova donor IVF may be candidates for NC-IVF.

Problems with NC-IVF include: premature LH surge, which occurs in 10-15% of patients, and less commonly failure to obtain an egg at the time of the follicle aspiration,. Occasionally fertilization may not occur (even with the use of ICSI) or embryo growth may suboptimal with failure of an embryo to develop to an appropriate stage prior to planned embryo transfer. When compared with stimulated IVF utilizing single embryo transfer, the pregnancy rates should be equivalent between NC-IVF and stimulated IVF. Studies comparing these 2 types of IVF are needed but our personal experience supports this notion.

Natural Cycle Frozen Embryo Transfer (NC-FET)

At Dominion Fertility, we only perform NC-FET in patients who have regular menstrual cycles. NC-FET is less expensive, simpler for the patient and the pregnancy rates are equal to medicated FET. In NC-FET, the menstrual cycle is monitored in the same fashion as described above. A single injection (hCG) is given to the patient for the entire treatment cycle. Seven days later, embryo transfer is performed. It’s just that simple! The entire treatment takes one menstrual cycle or about 4 weeks to complete.

We have been performing NC-FET for several years now and our data shows equal pregnancy rates in with NC-FET or medicated FET. In our opinion, the only draw back to NC-FET is that it requires the IVF center and patient to be flexible with respect to scheduling of the embryo transfer as this date can only be estimated. With a medicated FET, the exact date and time of the embryo transfer can be programmed before beginning the treatment.