A surrogate will frequently be prescribed intramuscular injections of progesterone. These are the injections your surrogate is most likely least looking forward to taking, and, if she mentions her injections, these are the medications she is most likely talking with you about.
The hormone is used to help aid in sustaining a pregnancy achieved through IVF and is typically given daily for the first ten to twelve weeks. The progesterone is mixed with an oil to create an injectable compound. There are several different types of oils that can be used for this process. Here’s a breakdown of the most commonly used oils for this purpose.
Ethyl Oleate- This is a type of oil you may not be familiar with. It is created from a human fatty acid created by the body when ethanol and oleic acid combine. It is, by far, the thinnest of the oil compounds for intramuscular injection. This allows for a smaller gauge injection needle. It is also the most often prescribed oil compound.
Olive Oil– Olive oil is also commonly compounded with progesterone. While it is thicker than ethyl oleate, thus requiring a thicker needle, many women report that this blend offers some of the easiest absorption into the muscle.
Sesame Oil. This is oil tends to be a thinner compound than the olive oil blend. Typically, the thinner the oil the easier the absorption of the compound will be. Better absorption limits the size and sensitivity of the lumps which often form at the injection sites. Allergic reactions can occur with sesame oil, and in that instance the patient will often be switched to progesterone in a different oil base, typically ethyl oleate. Many of our surrogates tell us that sesame oil results in some of the most manageable injection site tenderness.
Peanut and Cottonseed Oils. These oils are typically used the least. Peanut oil tends to be rather thick and carries the potential for severe allergic reaction at the injection site. Cottonseed oil is a thinner compound and is reported to cause less intense pain at the injection site.
Doctors tend to prescribe a certain oil time and time again due to their personal preference. No one oil has shown to produce a significant benefit across the board when compared against another. While some patients report far less pain with one type of oil vs. another, a different woman may report experiencing the exact opposite reaction to the same oil compounds.
More important than the oil type is ensuring that the injection sites are properly identified and that injection site tenderness is not the result of allergic reaction.