Send us Fan Mail
Progesterone-in-oil shots, also known as PIO shots, are one of the most feared and hated parts of IVF. They are uncomfortable, intimidating, and often leave patients wondering: “Do I really need this, or is my fertility doctor just being cruel?”
In this episode of Taco Bout Fertility Tuesday, Dr. Mark Amols explains why progesterone matters for implantation, how estrogen and progesterone work together to prepare the uterine lining, and why the type of embryo transfer cycle changes everything.
The key question is not simply whether progesterone shots are better than vaginal progesterone. The real question is whether your body is making progesterone on its own.
Dr. Amols breaks down the difference between ovulatory or modified natural frozen embryo transfers and programmed frozen embryo transfers. In an ovulatory cycle, the body forms a corpus luteum and produces progesterone naturally. In a programmed cycle, there is no ovulation, no corpus luteum, and therefore no natural progesterone production — meaning all progesterone support must come from medication.
This episode also reviews the research comparing daily progesterone-in-oil shots, vaginal progesterone alone, and combination protocols using vaginal progesterone plus intermittent PIO injections. The data shows why vaginal progesterone alone may not be enough in programmed frozen embryo transfer cycles and why many clinics still rely on PIO for reliable progesterone support.
Dr. Amols also discusses progesterone blood levels, why levels can be hard to interpret with vaginal progesterone, why clinics may differ in their protocols, and how some patients may be candidates for fewer injections or modified natural cycles.
If you are preparing for an embryo transfer, taking progesterone, or wondering why your clinic recommends PIO shots, this episode will help you understand the science behind the shot — and hopefully hate your doctor a little less.
The bottom line: fertility doctors are not sadists. Progesterone-in-oil may be a literal pain in the butt, but in some embryo transfer cycles, it has an important purpose.
Thanks for tuning in to another episode of 'Taco Bout Fertility Tuesday' with Dr. Mark Amols. If you found this episode insightful, please share it with friends and family who might benefit from our discussion. Remember, your feedback is invaluable to us – leave us a review on Apple Podcasts, Spotify, or your preferred listening platform.
Stay connected with us for updates and fertility tips – follow us on Facebook. For more resources and information, visit our website at www.NewDirectionFertility.com.
Have a question or a topic you'd like us to cover? We'd love to hear from you! Reach out to us at [email protected].
Join us next Tuesday for more discussions on fertility, where we blend medical expertise with a touch of humor to make complex topics accessible and engaging. Until then, keep the conversation going and remember: understanding your fertility is a journey we're on together.