Question about natural FET

[kristin]

Hi Dr. Wisot,

Thank you so much for taking the time to answer our questions! I have a question about natural FET that I'm confused about and hoping you can answer.

If the reason for doing a natural FET rather than a traditional medicated one is only to avoid taking supplemental estrogen, is it necessary or advantageous to wait for ovulation to time the transfer, or would it be possible to start progesterone when the lining got thick enough and then time the transfer based on when progesterone was started, basically ignoring the follicle that would have been developing? In your opinion, would either way have better outcomes than the other?

Thank you!

Kristin

[Dr. Wisot]

In a natural FET cycle (not y=using estrogen) you can start progesterone before ovulation when the endometrium is thick enough.

Either that or timing it by ovulation should give equivalent results. The only problem would be starting it too late.

Arthur L. Wisot, M. D.
Reproductive Partners Medical Group
Redondo Beach, California

[kristin]

Thanks for responding so quickly! I have a couple other questions...

What happens to the follicle that was developing if progesterone is started before ovulation? Will it eventually ovulate, or will starting the progesterone prevent ovulation from occurring?

Also, if ovulation doesn't occur, what provides the estrogen that the corpus luteum normally creates? Is it then necessary to supplement with estrogen after the transfer?

Thanks again!

Kristin

[Dr. Wisot]

The follicle should still ovulate. The only effect of the progesterone should be on the endometrium.

Even if it does not ovulate the granulosa cells should still continue to produce estrogen. If you get pregnant then the hCG will keep the corpus luteum producing estrogen and progesterone.

Arthur L. Wisot, M. D.
Reproductive Partners Medical Group
Redondo Beach, California

[kristin]

Thank you!