Fertility
What to Know About Progesterone in Oil Injections for Fertility
Progesterone in oil is an injectable medication often used off-label as part of fertility treatments.
Progesterone in oil is injected into the muscle once a day for several weeks. Injection-site reactions are common but can often be managed with ice or heat.
It’s important to follow proper injection technique when taking progesterone in oil to prevent infection and lower the risk of injection-site reactions.
Progesterone is a hormone in the body that plays an important role in fertility. It helps thicken the lining of the uterus, which helps a fertilized egg implant and grow. Low levels of progesterone can make it harder for you to become pregnant and make miscarriage more likely.
Progesterone in oil is an injection that helps raise progesterone levels in the body. It’s often prescribed if you’re trying to become pregnant and have a history of miscarriage or preterm birth. It’s usually taken as part of fertility treatments, like intrauterine insemination (IUI) or in-vitro fertilization (IVF).
Progesterone in oil is an injectable medication that’s FDA-approved to treat abnormal bleeding of the uterus or missing menstrual periods. However, it’s most often used off-label as a fertility treatment.
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As the name implies, the injection contains progesterone dissolved in sesame oil. It’s a thick, yellow oil that’s injected into a muscle. The body then absorbs the injected progesterone into the bloodstream.
Progesterone in oil injections can help raise the chances of pregnancy and lower the risk of miscarriage for certain people.
Progesterone plays three main roles in fertility:
It thickens the lining of the uterus to help a fertilized egg implant and grow.
It prevents early contractions.
It helps stop the mother’s immune system from attacking the fetus.
Low levels of progesterone can make it harder for your body to become pregnant and carry a pregnancy to term. So progesterone in oil is used to help keep progesterone levels high enough to help prevent these issues from happening.
The typical dose of progesterone in oil for fertility treatment is 50 mg (1 mL of oil) injected into the muscle once daily. But the dose can range from 25 mg to 100 mg.
You’ll often start progesterone in oil injections after ovulation or at the time of your embryo transfer. It’s usually taken for the first 6 to 12 weeks of pregnancy, but this varies. Your healthcare provider will tell you when to start and how long you’ll need to continue the daily injections.
It’s important to use proper technique when you inject progesterone in oil. It comes in a multi-use vial, so you’ll draw up several doses out of the same vial. Progesterone in oil must be injected into a muscle, so you’ll use a longer needle (usually 1 to 1.5 inches long). It’s typically injected into the upper outer buttock area. But your provider can suggest other locations if needed. Be sure to rotate injection sites with each dose to help prevent injection-site reactions.
Here are the basic steps to follow when injecting progesterone in oil:
Wash your hands, and arrange your alcohol swabs, syringe, needle(s), and sharps container close by.
Use an alcohol swab to wipe the top of the progesterone vial (you’ll do this before each injection).
Open the sealed syringe and needle using the tabs at one end, then twist the needle onto the end of the syringe. (Some syringes may come with a needle already attached.)
Pull back on the end of the syringe until the stopper is at the 1 mL line for a 50 mg dose.
Insert the needle into the rubber stopper of the vial, and inject the air into the vial.
Keeping the needle inside the vial, turn the vial upside down. Make sure the tip of the needle is under the surface of the liquid.
Pull back on the plunger until you have a little more than 1 mL of liquid in the syringe. If you see air bubbles, gently flick or tap the syringe to help them rise to the top. Then push on the plunger to remove them from the syringe.
Once you have 1 mL of liquid, remove the needle from the vial.
If your healthcare provider has given you a different needle for the injection, you can now twist off the old needle at the base and attach the new one. Place the used needle into the sharps container.
Use an alcohol swab to clean the injection site and allow the area to dry. It will sting if you inject through the wet alcohol. Don’t blow on the area to try to get it to dry faster — bacteria from your mouth can raise the risk of an infection.
Insert the needle all the way into the muscle, using a quick, dart-like motion.
Press down on the plunger to inject the medication. Use slow, steady pressure until all of the liquid is gone from the syringe.
Remove the needle and place the syringe into the sharps container.
Note: If your healthcare provider gives you two different needles for injection, the one with the lower gauge number (usually 18 gauge) is for drawing up the dose. The one with the higher gauge number (usually 22 or 23 gauge) is for injecting.
The gauge is how wide the needle is. A lower gauge has a larger opening and makes it easier to draw up the oil, but a higher gauge is less painful to inject.
After you inject progesterone in oil, it takes about 8 hours for levels to peak in the body. Levels stay high for about 24 hours, which is why most of the time you’ll only need to inject progesterone in oil once a day.
Progesterone in oil is known for causing injection-site reactions. It can also cause side effects due to higher progesterone levels in the body.
Injection-site reactions are the most common side effect from progesterone in oil. You may have the following symptoms in the area where you inject it:
Pain
Bleeding
Redness or itching
Swelling or what feels like a lump under the skin
You may also have side effects from higher levels of progesterone in your body. These can include:
Sore or tender breasts
Nausea
Difficulty sleeping
Feelings of depression
Puffiness or swelling
Weight changes
These are also side effects from pregnancy, so it may be hard to know if the effects are from progesterone or not. Most of these side effects will go away once you stop your progesterone injections. But if they become bothersome, let your healthcare provider know.
You can apply ice to the injection site before and after your injection to help numb the skin and reduce swelling. Or you can try applying a warm compress instead — especially if you tend to tense up before an injection. This can help relax the muscle and help the oil absorb after the injection.
You can also warm the bottle of progesterone in oil by gently rolling it between your hands before drawing up the dose. This helps make the oil easier to inject.
After you inject, gently massaging the injection site can help keep a knot from forming. Walking around can also help with this side effect.
If you’re still having trouble with injection-site reactions, talk to your healthcare provider. They can help make sure you’re injecting progesterone in oil properly. They may also be able to prescribe a numbing cream, like lidocaine/prilocaine, to help.
Some people may be allergic to the sesame oil in commercially available progesterone injections. Compounding pharmacies can make progesterone in other oils, like olive oil or ethyl oleate if needed.
Progesterone also comes in oral capsules (Prometrium), vaginal tablets (Endometrin), and as a vaginal gel (Crinone). All of these forms can be used to help support a healthy pregnancy in the same way as progesterone in oil. They don’t require injections, but they’ll typically require two to three doses per day. And vaginal progesterone can cause vaginal irritation and discharge that may be uncomfortable.
A new formulation of progesterone called Prolutex is used outside the U.S. It’s injected under the skin instead of into the muscle. It’s currently in a phase 3 clinical trial in the U.S. that should be completed in 2024.
Progesterone in oil is considered one of the most effective progesterone medications used in fertility treatment. It’s clear that oral progesterone isn’t as effective as other forms.
Studies are conflicting when it comes to how progesterone injections compare with vaginal progesterone. However, a 2021 study reviewed over 1,000 people and found that progesterone in oil injection resulted in more live births (44%) than vaginal progesterone (27%). Half of the pregnancies in women who received vaginal progesterone ended in miscarriage.
Keep in mind that this study was specific to IVF with a frozen embryo transfer. So it doesn’t necessarily apply to other forms of fertility treatment. Your healthcare provider will help determine the best form of progesterone for you.
Progesterone in oil in an injectable medication commonly used off-label as part of fertility treatments. It helps raise the chance of pregnancy and lower the risk of miscarriage in certain people.
When used for fertility, it’s injected once daily into the muscle for several weeks. The most common side effects are injection-site reactions, but these can often be managed with proper injection technique.
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