What to Expect During IVF Stimulation Injections

You just opened the box. It is enormous. Eight different vials, three different pens, alcohol swabs, a sharps container, and instruction sheets in nine-point font. The hardest injection in IVF is the first one, when your own hands are shaking. After two doses your body will have built a small routine, and the rest of the cycle becomes logistics rather than fear. This post is the practical walkthrough: what to expect during IVF stimulation, how to set up your station, and what nobody tells you about the trigger shot and the progesterone in oil that comes later.

The medications you will inject, by class

A typical cycle uses three to five different injections running on overlapping schedules. The brand names change by country, but the classes do not. Knowing which class each drug belongs to is more useful than memorising the brand.

Gonadotropins drive follicle growth. Follicle-stimulating hormone (FSH) only products include Gonal-F, Follistim, Puregon, and Bemfola. Products that add luteinising hormone (LH) activity include Menopur and Pergoveris. All are subcutaneous, almost always given in the evening, into the abdomen.¹

GnRH antagonists prevent a premature LH surge. The two main drugs are Cetrotide and Ganirelix (sold as Orgalutran in some countries). They are subcutaneous, usually started on stim day five to seven and given daily until the trigger.

GnRH agonist is the surge suppressor used in long protocols. Lupron (leuprolide) is given subcutaneously, often in the morning, and continued through stim in long-protocol cycles.

The trigger shot completes egg maturation. Options include hCG products (Ovidrel, Pregnyl, Novarel) given subcutaneously or intramuscularly depending on brand, and Lupron trigger given subcutaneously.

Luteal support comes after retrieval, during the two-week wait, and while you are recovering after egg retrieval. Progesterone in oil (PIO) is intramuscular, given in the upper outer quadrant of the buttock. Vaginal alternatives (Endometrin, Crinone, compounded suppositories) replace or supplement PIO depending on clinic preference.²

The injection schedule will be written out on a calendar from your clinic. I tell patients to tape it to the fridge and cross off each dose as it goes in. Nothing fancy, but it prevents the "did I take the antagonist this morning" moment at midnight.

Subcutaneous vs intramuscular, the practical difference

These are two different injection techniques, and the difference matters because most patients fear the wrong one.

Subcutaneous injections use a short, fine needle, six to twelve millimetres long, inserted into the fatty layer of the abdomen or thigh. The sensation is a quick pinch, sometimes followed by a brief sting depending on the medication. Almost every stim medication is given this way. You can do them alone, and most patients learn by the second or third dose.

Intramuscular injections use a longer needle, typically one to one and a half inches, inserted into the upper outer quadrant of the buttock or, less commonly, the thigh. The sensation is heavier, and the site is sore for longer afterwards. Progesterone in oil is the main IM medication in IVF. Some clinics also give the hCG trigger intramuscularly, though most have moved to the subcutaneous Ovidrel.

The angle and reach of an IM injection in the buttock is awkward to do solo. Patients usually find this easier with a partner. If you are doing the cycle alone, ask your clinic about thigh IM technique or about switching to vaginal progesterone. Both are reasonable.

Setting up your station

The first time I inject anyone in clinic, I notice that the patients who have set up a calm physical station inject more easily than those who do it on a rushed kitchen counter. The setup matters because it builds a small ritual, and rituals lower anxiety.

Pick one flat, well-lit surface. A kitchen counter, the corner of a desk, the bathroom counter: anywhere stable that you will use every day. Using the same place each time tells your body what is about to happen.

Put a sharps container next to you, never across the room. Clinics supply these free, and pharmacies stock them. The temptation to walk a used needle across the room is exactly how needlestick injuries happen.

Lay out alcohol swabs, gauze, bandages, and an ice pack that has been in the freezer for fifteen minutes before you started. Ice the injection site for one to two minutes before the needle goes in. It numbs the surface meaningfully and is the single biggest comfort upgrade in self-injection.

Set a phone alarm for the dose time, every day. Stim medications work best on a stable schedule, within roughly a two-hour window. The trigger shot is far stricter, within five minutes of the exact time your clinic specifies. Two alarms, one fifteen minutes before, one at the time itself, is not overkill on trigger night.

Tape the printed protocol page to the fridge and tick off each dose. The combination of an alarm and a visual log makes missed doses very rare.

The actual injection, what nobody tells you

These are the small details that the clinic teach video glosses over but that patients ask me about constantly in week one.

Ice the site for sixty to ninety seconds before injecting. The numbing is real, not placebo. Pinch a generous fold of skin, about two inches, between thumb and forefinger and inject at ninety degrees, perpendicular to the skin, not the forty-five degrees that older videos show. Modern subcutaneous needles are short enough that ninety degrees is correct.

Inject slowly. Five to ten seconds for the plunger is the right pace, not a quick push. Faster pushes hurt more and increase site bruising.

Some medications sting more than others, and this is the medication chemistry, not your technique. Menopur stings on the way in because of its urinary-derived hormones and the diluent. Ganirelix sometimes burns. Gonal-F and Follistim are usually the most comfortable. If a medication that has been comfortable suddenly stings, check the technique. If a medication has always stung, that is the medication.

Bruising is normal. So is a small red welt, mild itching for a few minutes, and a tiny drop of blood when the needle comes out. Rotate sites systematically (left abdomen morning, right abdomen evening, or left thigh, right thigh, working in a small grid) so no site is hit twice in twenty-four hours. Never inject into a bruise, a scar, or a stretch mark.

I tell my patients the first injection is the hardest one. By day three you will surprise yourself. The needles are smaller than people remember, and the act becomes ordinary.

The trigger shot, the one with the most pressure

The trigger has more emotional weight than any other injection because the timing window is short and the consequence of getting it wrong is real. The trigger is given thirty-five to thirty-six hours before egg retrieval, and the maturation it produces is what allows the eggs to be retrieved at all.¹

Confirm the dose, drug, and exact time with the nurse the day of the trigger. Some clinics call you, others ask you to call them. Either way, do not assume the schedule on the calendar is correct without that day-of confirmation, because trigger time is often adjusted based on the final monitoring.

Set two alarms. One at fifteen minutes before, one at the time itself. The fifteen-minute alarm gives you time to wash hands, set up, and ice. The exact-time alarm is the moment the plunger goes in.

If you miss the trigger window by more than fifteen to thirty minutes, call your clinic's on-call line immediately. They can sometimes adjust retrieval time to compensate. Do not give the trigger silently and then mention it the next morning.

For an hCG trigger like Ovidrel, the injection is subcutaneous and feels like any other stim shot. For Pregnyl or Novarel, the medication has to be reconstituted from a powder, which adds a step and sometimes a longer needle if it is given intramuscularly. For a Lupron trigger, the injection is subcutaneous and usually easier than hCG.

Progesterone in oil, the late-cycle one nobody warned you about

Progesterone in oil enters the conversation only after retrieval, and most patients are surprised by how different it feels from everything that came before. It is a thick oil, given intramuscularly with a longer needle into the upper outer quadrant of the buttock. It is uncomfortable, and the site is often sore for a day or more.

The technique that helps most: warm the vial in your hand for five minutes before drawing up, so the oil flows more easily. Use a thinner draw-up needle to load the syringe, then switch to a longer twenty-two to twenty-five gauge needle for the injection itself. After the injection, apply a heating pad to the site for ten to fifteen minutes: this helps the oil disperse and reduces the next-day knot.

Knots, mild swelling, and site soreness are common. Rotate sides every day, draw a small grid pattern on each side so you do not stack injections, and walk for ten minutes after the dose to keep the oil moving.

Vaginal progesterone is an alternative for some patients. Endometrin tablets, Crinone gel, and compounded suppositories are all reasonable options, with comparable pregnancy outcomes in many studies.² The trade-off is that vaginal progesterone is messier and some patients find it harder to be consistent with twice or three-times-daily dosing. Discuss the options with your reproductive endocrinologist (RE).

What is normal at injection sites, and what is not

The vast majority of injection-site reactions are minor and predictable. The list of things that should prompt a call is short.

Normal: bruising of any size, a small red welt, mild itching for thirty minutes, soreness, a two-inch firm knot from an IM injection, occasional bleeding when the needle comes out.

Call clinic: spreading redness or warmth at the site, fever above 38°C, hives or wheezing after an injection (possible allergic reaction), persistent severe pain, or pus.

Stop and call right away: signs of anaphylaxis, meaning throat swelling, difficulty breathing, full-body hives. These are very rare with stim medications but possible. Most patients should never see this; knowing the picture means you do not waste minutes wondering.

Solo workflow vs partner workflow

There is a quiet assumption in much of the IVF content online that someone is going to inject you. Many patients do this entirely alone, and the cycle still works. The split is roughly this.

All subcutaneous injections (every gonadotropin, every antagonist, the subcutaneous trigger) are easily self-administered by the patient. Most patients learn within two doses. A mirror, a stable bracing position, and one in-person teach with your clinic nurse is all you need.

Intramuscular injections, especially progesterone in oil, are easier with a partner because the angle and reach to the buttock are awkward solo. If you have a partner who can be taught, the in-person nurse teach should include them (how partners can help through stim and retrieval). If you do not, ask your clinic about thigh IM technique or switching to vaginal progesterone. Both are real options.

Storage and travel logistics

Most stim medications are refrigerated. A small insulated lunch bag with a reusable ice pack works for daytime travel. Confirm with your specific medications which need refrigeration and which do not. The antagonist is sometimes stored at room temperature, while gonadotropins almost always need the fridge.

For air travel, carry medications in your carry-on, never checked, because hold temperatures are unpredictable. Most clinics will write a TSA letter for security if you ask. Keep the original packaging visible: security agents recognise pharmaceutical boxes.

For power outages, most stim medications tolerate room temperature for twenty-four to forty-eight hours per manufacturer instructions. Check the package insert for each specific drug rather than guessing.

What to expect during IVF stimulation: dos and don'ts

Readers search for the dos-and-don'ts list constantly, so here it is in plain form.

Do: inject at the same time each day, ice before each shot, rotate sites, eat a small snack twenty minutes before each dose, sleep on your side with a pillow between your knees as the ovaries enlarge, drink water steadily, walk daily.

Don't: skip the antagonist for any reason, take ibuprofen or other non-steroidal anti-inflammatory drugs during stim or the days around retrieval, run, twist, jump, or lift heavy weights from around day five onward, fly during stim if your clinic has advised against it, drink alcohol, use very hot baths or saunas, or have unprotected sex once the ovaries are noticeably enlarged.

For the longer explanation of why each of these matters, especially sex during IVF stimulation and what to expect day by day, the pillar post on stimulation is the place to start.

What to ask your clinic the day you pick up meds

The medication pickup is the moment to ask the practical questions about what to expect during IVF stimulation, because the nurse who hands you the boxes is the same nurse you may need at 11pm.

1. Which medications need refrigeration, and which do not?
2. What is the maximum out-of-fridge time for each, including the reconstituted Menopur?
3. Who do I call after hours if I miss a dose, have a reaction, or am unsure?
4. Will the nurse do the in-person teach for the first injection, or is it a video?
5. If I have a partner who will be helping with progesterone in oil, can they come to the teach?

What's next

• If you want the day-by-day map of what you will feel during stim: IVF Stimulation Phase: What the 10 to 14 Days Actually Feel Like
• If you want to understand which protocol you are on: Common IVF Stim Protocols: Long, Short, Antagonist Explained
• If you are watching for OHSS or want to understand the safety planning: OHSS: Ovarian Hyperstimulation Syndrome and How Doctors Prevent It
• If you have PCOS or a high AMH: Why PCOS Patients Get More Eggs and the OHSS Risk
• If a dose was missed or a cycle is cancelled: When Things Don't Go to Plan

Sources

1. ESHRE Guideline Group on Ovarian Stimulation, Bosch E, Broer S, et al. ESHRE guideline: ovarian stimulation for IVF/ICSI. Human Reproduction Open 2020;2020(2):hoaa009. https://doi.org/10.1093/hropen/hoaa009
2. Practice Committee of the American Society for Reproductive Medicine. Progesterone supplementation during the luteal phase and in early pregnancy in the treatment of infertility: an educational bulletin. Fertility and Sterility 2015;103(4):e27-e32. https://doi.org/10.1016/j.fertnstert.2014.12.128
3. American Society for Reproductive Medicine. In Vitro Fertilization (IVF) patient education. https://www.reproductivefacts.org/topics/topics-index/in-vitro-fertilization-ivf/
4. van der Linden M, Buckingham K, Farquhar C, et al. Luteal phase support for assisted reproduction cycles. Cochrane Database of Systematic Reviews 2015;7:CD009154. https://doi.org/10.1002/14651858.CD009154.pub3