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Biology Behind Marquette Method NFP

Updated: May 4, 2023

What’s the low down of the Marquette Method? What makes Marquette different from other methods of Natural Family Planning? How many days can we expect to abstain if we are avoiding a pregnancy?

Before I get into the Marquette Method, here’s a helpful overview of a woman’s naturally occurring fertility if she’s in normal cycles (as opposed to returning fertility after recent pregnancy). The first several days of a woman’s cycle are called menstruation. It’s when her uterus contracts, causing cramping, and then sheds the unused fertile uterine lining. This bleeding indicates that in the previous cycle, an egg was released (ovulation occurred) but no fertilization took place and the egg died. This process is a normal one and indicates a woman’s health that she has regular menstruation between every 24-42 days.

Once her uterine lining has been shed bleeding stops. For some women there is a period of vaginal dryness that can last a few days. Other women notice mucus changes soon after menses stops. When the change in mucus does occur, this is an indication that the hormone estrogen is on the rise. Estrogen rises for several reasons I won’t get into in this post. Estrogen has several actions, one of which is to change the color and consistency of mucus at the cervical opening. Estrogen also tells a woman’s ovaries to nourish and mature an egg in preparation for ovulation. This rise continues over several days to a week during the first half of the cycle, called the follicular phase.

When an egg has reached maturity and is ready to be released, luteinizing hormone, or LH, is rapidly sent out from the woman’s brain. This is referred to as the Peak or LH surge. This surge in LH precedes ovulation, or release of an egg, by 12-24 hours. This is associated with a slight dip in estrogen, which can cause estrogen withdrawal bleeding or spotting mid-cycle. When a woman ovulates in her cycle varies from cycle to cycle. This is dependent on many factors including sleep, stress levels, diet and exercise levels.

The follicle from which the egg was released changes from a follicle to a corpus luteum upon ovulation. The corpus luteum is responsible for secreting estrogen and progesterone. The rise in progesterone after ovulation is often observed by a shift in basal body temperature. These hormones remain elevated for about 2 weeks. If fertilization occurs, these hormones initially support the pregnancy. If no fertilization occurs, the egg dies, the corpus luteum eventually shrivels up and also dies. When the corpus luteum dies, estrogen and progesterone quickly drop and menstruation is triggered, thus beginning a new cycle.

Rising and falling estrogen and LH looks something like this:

In some forms of NFP, the signs of fertility observed by the woman primarily are the result of estrogen rising, mainly cervical mucus and even changes to the cervix itself. Other forms of NFP also monitor for the basal body temperature shift caused by rising progesterone. However, mucus is a very early change and temperature rise or shift is a late change. What if there was a way to tighten up that window of time and know with 98% certainty the exact day that ovulation occurred? This would result in more usable days for intercourse (i.e. less abstinence) for couples intending to avoid a pregnancy. For couples trying to conceive, the fertile window is tightened to allow for focused intercourse when the couple is most fertile. Research indicates that focused intercourse helps couples acheive a pregnancy sooner than those who are not focusing intercourse.

Marquette Method NFP utilizes technology to monitor in real time a woman’s hormonal status. The Clear Blue Fertility Monitor checks for metabolites of estrogen and LH in a woman’s urine. The presence of these hormones gives couples a very accurate and objective picture of their fertility status. When using the Marquette Method, a woman will test her urine every day beginning on Cycle Day 6. Her monitor will tell her if her estrogen has risen and then when an LH surge is detected. She then can apply an evidence based algorithm to this information to tighten up the fertile window allowing a couple to successfully avoid a pregnancy while reclaiming as many days as possible for sexual intimacy. Interested in learning more? Book a Marquette Method Lite class today to fully learn the method! The booking also includes 3 cycles of charting support with a licensed Registered Nurse who can help with any questions you might have. Get started today!

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