So much great information on HA is available in the medical literature. it really is a shame that your average OB is not better educated.
My friend was recently told that she had less than a 50% chance of regaining cycles if she gained weight / cut exercise. Way to pull a stat out of where the sun doesn't shine doctor!
Here's an article where they followed women with FHA for an average of eight! years. The doctor counselled them on the advisability of gaining some weight and cutting exercise to help restore cycles and improve bone mass density. 70% of the women started cycling again.
Those 70% gained between 6.5 - 28 pounds. Cycles were regained for the most part between years 1 and 2 of changes. (Keep in mind that these were gradual changes and many of the women were on either HRT or birth control pills, with a break every 6 months or year to see if they were cycling).
Take a guess as to the weight change of the women who did not start cycling again. Surprise surprise, either no change or a decrease of a pound or two. Unfortunately they don't mention changes in exercise.
I also think that the cycles could have resumed more quickly had the weight gain / exercise changes been made in a shorter timeframe. Most of these women were not trying to conceive at the time the study started, so had less incentive to restore cycles in a short timeframe.
This is another interesting article where three menstrual cycles were examined in either sedentary women, or "moderate exercisers". (On average, running 20 miles per week plus 5 hours of other, nonspecified, exercise).
In the sedentary women, 91% of menstrual cycles were ovulatory, 9% (all in one woman) had a luteal phase defect. In the exercising women, 45% were ovulatory, 43% had a luteal phase defect, and 12% were anovulatory.
There was no significant difference in energy availability between the ovulatory and LPD cycles in the exercising women (although both were lower than the sedentary women). Again, though, I bet you can predict what the energy availability looked like in the anovulatory cycles... yup - MUCH lower. These women had an average energy balance of about -1000 calories per day, and also ate only about 50% as much fat as the others.
So even in recreational exercisers who are cycling, the energy deficit can cause cycle issues.
Speaking of luteal phase (LP) defects, I now have four postpartum periods to compare in my own life. In all three live birth cases, my first cycle was while still breastfeeding, but I weaned right around the time the second started.
After #1 was born my LPs were as follows (P = I used Prometrium 200mg 1x/day) (bmi 21.9):
4, 8, 7, 16P, BFP
After #2 (bmi 20.7):
6, 6, 7, 9, 9, 9, 10, 10, BFP [
After my mc (bmi 21):
7, 14P, 14P, 14P, 14P, 10, 12, 13P, 14P, 18P, 17P, 12
After #3 (bmi 20.3):
10, 10, 11, 12, 12, 12
Guess what the difference is after #3 when my LPs have been much better and gotten longer much more quickly - VERY LITTLE EXERCISE!
Now, I ride my bike maybe once a week and play ice hockey once a week. A fair bit of walking bc of chasing after the kids, and I lift weights once in a blue moon.
After #1 and 2 were born I was playing hockey 2-3x/week, biking to/from work, and lifting weights 2x/week.
More food for thought. Pun intended ;)