There are typically three medications given to a surrogate during her journey: Lupron (to shut down her ovaries temporarily), Estrogen (to thicken the lining of the uterus) and Progesterone (to prepare the lining to receive the embryo). This blog sets the story straight about progesterone... its uses, delivery systems and efficiency. 

In a fertile woman, Progesterone is a hormone produced by the ovaries. It is first released during the middle of the menstrual cycle. Progesterone prepares the lining of the uterus (endometrium) to allow a fertilized egg (embryo) to implant. If an embryo implants into the lining of the uterus, the ovary will produce progesterone until between 7 and 10 weeks gestation. At that point, Progesterone is then produced by the placenta for the remainder of the pregnancy. 

In the beginning of the surrogates cycle, Lupron puts the surrogate in "medical menopause" by turning off her ovaries and shutting down the production of progesterone.  Because progesterone is vital in both receiving an embryo and carrying a fetus, progesterone is given to a surrogate for up to 16 weeks. Without ample progesterone levels, a viable pregnancy will not occur. 

Progesterone is available in 5 delivery systems: injections, gel, suppositories, vaginal powder capsule and an oral medication.  Pharmaceutical companies and doctors alike have run studies to detect the levels and effectiveness of all 5 forms.  Each one of these studies uses the injection as the gold standard to measure all other forms by. In most of the research available, there are significant studies that deem all four of the other non-injectable delivery systems of progesterone if not equally, sometimes more effective than the intramuscular injections (as noted in this study).  

So, if there are significant studies that claim to have proof that other delivery systems are equally effective, why aren't Reproductive Endocrinologists hanging up their needles?  The discrepancy lies in the information and studies that are not available.  Because it is often times the manufacturers of these other drug options who pay for the studies, they are not required to publish any or all studies that may in fact state that the injectable version of progesterone still reigns king. Until there is significant unbiased data available to REs world wide, expect that the needle will still be a part of the surrogacy process. 

Progesterone in oil is given as an intramuscular injection in the upper buttocks, near the hip. Pain at the injection site is common. The different oils used in the injections differ in amount of pain caused. 
There are several different types of oil used to deliver progesterone through the needle and into the body: cottonseed oil, peanut oil, sesame oil, olive oil... the list goes on. Allergic reaction is possible to all oils but most commonly to sesame and peanut oil.  However, Ethyl Oleate is the thinnest oil available. Because of this, a smaller needle can be used, and it does rarely causes lumps at the injection site. Ethyl Oleate is not carried at all pharmacies and may have to be ordered separately.  

While not everyone has issues with the injection site itself, lots of women do suffer from bruising, lumps and general soreness. Warming the oil before injection will help it flow more smoothly into the muscle and will avoid lump formation at the injection site. You can not put the bottles in the microwave but tucking them under your breast in you bra can help raise the temperature to match that of your body temperature.  Using heat, rather than ice, for pain control will help prevent lumps and allow the drug to properly disperse. Learn more here.

While Progesterone injections may not be the best part of your surrogacy journey, they are a vital piece of the puzzle.  Progesterone, along with Estrogen and Lurpon, are the trifecta of medications that allow you as a surrogate to receive embryos and carry surrogate babies. No matter how big the needle, I am confident you can handle it... after all, your already a mom and a surrogate! 

A special thank you to Dr. Michael Murray from Northern California Fertility Medical Center for his expert opinions and contribution to this piece.