Progesterone in Oil Intramuscular Injections at Hopeful Beginnings IVF
Every fertility journey has its delicate moments — the ones where science meets patience and hope meets precision. At Hopeful Beginnings IVF, one of those moments often arrives with a small vial and a deep breath: the progesterone in oil intramuscular injection, sometimes called the “PIO shot.”
This part of treatment can feel intimidating at first. You’re tired, juggling medications, and suddenly handed a syringe that’s supposed to help your body hold on to something precious. But you’re not doing this alone. Our nurses guide every patient through the process — when to inject, how to make it easier, and what to expect in the hours that follow.
These injections play a quiet yet powerful role. They help your uterine lining stay receptive and strong while your body prepares for or supports early pregnancy after an embryo transfer.
What Exactly Is Progesterone in Oil?
Progesterone is one of those behind-the-scenes hormones that holds everything together in early pregnancy. It helps thicken the uterine lining and prevents it from shedding too soon — almost like keeping the soil rich enough for a seed to take root.
Under normal circumstances, the corpus luteum — a structure that forms in the ovary after ovulation — produces progesterone naturally. However, during IVF treatment, the medications that stimulate the ovaries can interrupt or reduce this natural rhythm. That’s why most patients need supplemental progesterone.
The intramuscular form, known as progesterone in oil (PIO), is simply progesterone suspended in a sterile oil — usually sesame, peanut, or cottonseed oil. Once injected, the oil releases the hormone slowly over about 24 hours, helping maintain a steady and consistent hormonal balance. (Healthline, 2023)
Compared with pills or vaginal gels, this injectable form provides more consistent absorption and stronger hormone levels, which can make a measurable difference in implantation success and early pregnancy outcomes. (GoodRx, 2024)
