Because we do a lot of talking about conception, hormones, cycles, etc I thought it might be a good idea to review what a normal menstrual cycle should look like.  Let’s be real – most of us haven’t likely reviewed this since high school.  SO many of us have irregularities and imbalanced that we may have forgotten how things are supposed to work so let’s review!

Day 1 equals the first day you get your period.  Both estrogen and progesterone (your two main sex hormones) are low – this causes the uterine lining to shed and the beginning of your cycle.

A typical cycle runs between 2-7 days (typically longer when you are younger, and shorter in your older years).  During this time the lining sheds when no pregnancy is detected.  Afterwards, estrogen levels begin to rise.  Estrogen is responsible for building the uterine lining, making it thick and cosy for a potential fertilized egg to implant in.  Estrogen is also responsible for other things in the body such as helping your bones to grow strong and continue that way throughout the aging process, buffers mood (adjusts levels of serotonin) and gets you obsessing over babies.  During this time your body will select at least one egg to begin it’s maturation.

In a textbook style cycle – day 14 come around – your uterine lining is at a good thickness and your egg is mature enough to be released.  At this time two of your other hormones – LH (luteinizing hormone) and FSH (follicle stimulating hormone) come into play.  If you have ever taken a ovulation test, these are the hormones it is watching for.  The spike of these hormones will release the mature egg (if more than one egg is released and fertilized – this is where the potential for non-identical twins comes into play) After the rapid increase, these hormones will fall just as quickly as their job is completed.  The release of the egg will then put you into the second phase of your cycle – triggering progesterone levels to increase and estrogen to decrease.  Progesterone then takes over work with the uterine lining.  Estrogen has build it up (ie stacked one brick on top of each other) and now progesterone will come in and stabilize that wall to ensure it’s ready for either pregnancy or your next cycle (adds in the cement to hold everything stably in place)

Good progesterone levels are essential for getting pregnant and maintaining a pregnancy. If you have had multiple miscarriages (especially early on) low progesterone levels is something worth investigating.

One of the key things throughout a healthy menstrual cycle is that the main sex hormones – estrogen and progesterone – stay in a good balance of one another.  Having levels that are two high or low of either hormone may result in symptoms such as PMS and difficulties conceiving.

Once the egg reaches the uterus – if no fertilization has taken place, progesterone levels drop, your uterus sheds it’s lining and the cycle starts all over again.

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