What you're injecting and why
The stimulation phase uses two types of medication working together. The first grows multiple follicles simultaneously. The second — added mid-cycle — prevents them from releasing too early. Each person uses one from each category, not all of them.
Days 2–12 · evenings
Gonadotropins
Gonal-F or Follistim (FSH)
+ Menopur (HMG)
GonadotropinsHormones that stimulate the ovaries to grow multiple follicles at once — FSH (follicle-stimulating hormone) and HMG (human menopausal gonadotropin). are the main stimulation medications. They tell the ovaries to grow multiple follicles simultaneously, rather than the single follicle that develops naturally each month. Gonal-F and Follistim are the same medication made by different manufacturers — one or the other is prescribed, not both. Menopur is typically given alongside one of those.
Side effects: Breast tenderness, bloating, mood swings, injection site reactions, abdominal discomfort. Ovarian hyperstimulation syndrome (OHSS) is possible but occurs in under 1% of cycles.
Days 7–12 · mornings
GnRH Antagonist
Cetrotide or Ganirelix
Added mid-cycle — typically around Days 7–9 — once follicles have grown enough that there's a risk of premature ovulation. The GnRH antagonistA medication that blocks LH release, preventing the follicles from ovulating before retrieval can happen. suppresses the natural LH surge that would trigger ovulation. It continues every morning until the trigger shot. Cetrotide and Ganirelix are equivalent — one or the other is prescribed.
Side effects: Abdominal bloating, minor injection site reactions, occasional headache or nausea. Incidence under 5%.
Medication doses are personalized and adjusted throughout the cycle based on how follicles are responding. The protocol seen at orientation is a starting point — what's actually taken day-to-day is directed by the nurse after each monitoring visit.
The daily rhythm
The stimulation phase has a consistent structure once it starts. On monitoring days, it runs like this:
A monitoring day — what it looks like
7–9am
Morning monitoring appointment. Bloodwork and ultrasound. Takes about 45 minutes total. Happens at the clinic — no virtual option during stimulation.
Afternoon
Nurse call or portal message. Results from the morning appointment, updated medication instructions for that evening, and the next monitoring appointment scheduled.
Evening
Injections — same time every day. Gonadotropins in the evening. Once the antagonist starts, it moves to mornings and continues alongside the gonadotropins each evening.
Non-monitoring days
Injections continue on schedule. No clinic visit. The afternoon call from the previous monitoring day carries the instructions.
What stood out from orientation
The thing that surprised me most in orientation wasn't the injections — it was how completely the monitoring schedule controls the day. A 7am appointment in Manhattan, including weekends, for up to two weeks. That's not a small ask. Planning around it before Day 2 — not the morning of the first appointment — makes a real difference.
Monitoring appointments
Monitoring appointments typically happen on Days 5, 8, and 10 of stimulation — though the exact schedule varies based on individual response. Some people have more, some fewer. Each visit involves bloodwork to check hormone levels and a transvaginal ultrasound to measure follicle growth.
The appointments happen between 7–9am, seven days a week. They can't be rescheduled or skipped — the protocol is adjusted in real time based on what the monitoring shows, and delays affect the timing of everything that follows.
Allow about 45 minutes for each visit. The clinic can be busy in the morning monitoring window — arriving on the earlier side helps.
Follicle counts — what they mean
At each monitoring appointment, the ultrasound measures the number and size of developing folliclesFluid-filled sacs in the ovaries, each potentially containing a developing egg. Size is measured in millimeters — around 18–20mm is considered mature and ready for retrieval. in both ovaries. The goal is to have multiple follicles growing to an appropriate size before the trigger shot.
Follicle count is not the same as egg count. Not every follicle contains a mature egg. Not every egg retrieved will be mature. The final frozen egg count — which comes the day after retrieval — is always lower than the follicle count seen during monitoring. That's normal and expected.
The follicle count during monitoring is useful information, not a prediction. It's worth staying curious about the numbers without getting too attached to them — they're a snapshot of where things are, not a guarantee of what the final count will be.
The afternoon call
After every monitoring visit, a nurse calls in the afternoon — or sends a message through the patient portal — with that day's results and updated instructions. This call is where the medication doses for that evening are confirmed, any adjustments are made, and the next appointment is scheduled.
The call comes after the lab processes the morning bloodwork — timing varies but is typically early-to-mid afternoon. Being reachable for this call matters because the injection timing that evening depends on what it contains.
Something I didn't expect
The orientation mentioned this call but didn't fully convey how central it is to the whole rhythm. The morning appointment, the waiting, the afternoon call, the injection that evening — that cycle repeats for nearly two weeks. Understanding it as a loop, not a series of separate events, makes the mental load of it easier to hold.
I knew about the injections before I started. What I didn’t fully grasp was the rhythm — morning appointment, waiting, afternoon call, evening injection, repeat. For nearly two weeks. Including weekends. It doesn’t sound hard until it’s your entire schedule. The injections are manageable. The calendar is what actually needs planning for.
What to expect physically
Physical experience during stimulation varies widely. Some people feel minimal side effects. Others feel them significantly. What's generally considered typical:
Bloating is the most commonly reported experience — as follicles grow, the ovaries enlarge, and the sensation of fullness or pressure in the lower abdomen is common. It tends to increase toward the end of stimulation and often peaks a few days after retrieval.
Fatigue is common, as is mild cramping, breast tenderness, and mood fluctuations from the hormonal changes. These vary by person and by day.
Injection site reactions — minor bruising, redness, or sensitivity at the injection site — are normal. Rotating injection sites helps.
What's worth contacting the clinic about: severe pain, significant rapid bloating, rapid weight gain (more than 2–3 lbs in a day), or difficulty breathing. These can be signs of OHSSOvarian Hyperstimulation Syndrome — when the ovaries over-respond to stimulation medications. Mild OHSS is relatively common; severe OHSS is rare but serious. and should be evaluated.
What I'd tell a friend
The injections aren't the hard part. I say this as someone who was genuinely scared of them beforehand. The needle is small, the motion becomes routine by Day 3, and most people find they're manageable within a few days. What actually needs planning for is the calendar — morning appointments every day or two, including weekends, for nearly two weeks. Clear your mornings. Tell work something vague but true ('I have a recurring medical appointment'). The physical part is fine. The schedule is the thing.
What surprised me
How social it became. I'd expected to do this quietly and alone. Instead I ended up telling more people than I planned because the schedule was impossible to hide, and the responses were almost universally kind and curious. A few people opened up about their own fertility experiences in ways I hadn't expected. The isolation I'd anticipated largely didn't happen.
Audio note coming soon — what the stimulation phase actually felt like, once it's done.
Injection technique
All stimulation injections are subcutaneousInjected into the fatty layer just beneath the skin — not into muscle. Typically given in the lower abdomen, an inch or two below and to the side of the navel. — into the fatty layer of the abdomen, not muscle. Most people find them manageable within the first few days. The needles are small. The orientation includes injection training and links to manufacturer videos for each medication.
NYU Langone provides training video links for each specific medication — Gonal-F, Follistim, Menopur, Cetrotide, Ganirelix, and both trigger options. Watching the video for each medication before the first injection is worth the time. The techniques differ slightly between them.
A few practical notes from the orientation materials: take injections at the same time each day, rotate sites to reduce bruising, and keep medications that require refrigeration cold right up until use. If something in the injection feels wrong — unexpected pain, medication not going in correctly — contact the clinic before proceeding.
The full medication breakdown — what each drug does, storage requirements, and pharmacy cost comparison — lives on the Medications page.