Ovarian stimulation: complete guide with timelines, risks, and practical tips

What is ovarian stimulation and when is it recommended?

Ovarian stimulation is the first major step in an assisted reproduction treatment such as IVF or a fertility preservation plan. In a natural cycle the ovary usually matures a single dominant follicle; with medication (gonadotropins and GnRH modulators) we aim for several follicles to mature at the same time, giving you more eggs — and therefore more options.

At Love Fertility Clinic we like to make one thing clear: follicle does not equal egg. A follicle is a small fluid-filled sac inside the ovary; it may contain an egg… or it may not. Understanding this distinction helps avoid false expectations when we share follicle counts at your ultrasound scan.

When do we recommend ovarian stimulation? When you need IVF because of a fertility problem, when you are a single mum by choice or a same-sex female couple and we consider this the best option, or when, after assessing your fertility, we see that egg freezing (vitrification) is a smart move for the future. In our day-to-day practice, if your AFC (Antral Follicle Count) and/or AMH (Anti-Müllerian Hormone) are below expected levels, we suggest stimulation and vitrification — preserving today’s egg quality to use tomorrow. We also recommend it to patients who wish to delay motherhood beyond 35, even with a good ovarian reserve, because time significantly affects egg quality.

We also discuss less common scenarios, such as empty follicle syndrome: occasionally, despite good follicular growth, no eggs are retrieved. It is rare and its cause is not fully understood; we mention it so you know the process is not a flawless machine, but that we are with you at every step.

Our priority is that you understand the purpose: to maximise your options with a personalised, honest strategy, explained in plain language and backed by close monitoring.

Ovarian reserve: AMH and Antral Follicle Count (AFC) before you begin

Before prescribing a single unit of medication, we do our homework. Your ovarian reserve is assessed with:

• AFC by transvaginal ultrasound scan, ideally between day 2 and 5 of your cycle, although it can be performed at any time depending on your availability.
• AMH – Anti-Müllerian Hormone via a blood test.
• And always, your age and reproductive plans.

These results help us set expectations and plan the dose. The antral follicle count is interpreted alongside AMH, age and clinical history. A single number does not determine your reproductive outlook.

These results guide clinical decisions. For instance, with low AMH/AFC we usually suggest starting treatment sooner and, depending on the type of treatment and the patient’s profile, we may consider more than one cycle to accumulate eggs or embryos. If the reserve is high, we fine-tune doses carefully to minimise discomfort and reduce the risk of over-response.

In addition, our Fertility Test (ultrasound scan + AMH + gynaecological review) gives you an accurate snapshot of where you stand right now. Many women tell us that this information alone is a relief: they can decide whether to freeze eggs now or fast-track their motherhood plan. We also share our practical rule for setting goals from the very first visit: as a general guideline, we aim to vitrify at least 10 eggs to ensure good future odds, adjusting for age and individual circumstances.

How it works step by step (day 2–3, medication, and monitoring)

The typical plan begins on day 2–3 of your period with daily subcutaneous injections for 10–12 days (this may vary). We schedule monitoring appointments every few days to:

1. Ultrasound scan: measure the size and number of follicles in each ovary.
2. Hormone blood test when useful: check estradiol levels and fine-tune the treatment if needed.
3. Real-time dose adjustment: we increase or decrease medication based on your response.

We see this as a team effort: you self-inject (we teach you how and share comfort tips), and we monitor to ensure harmonious growth. We always explain that the number of follicles does not equal the number of eggs and that quality can vary — just as not every sperm in a semen sample is viable, the same applies to eggs.

If at any check-up you notice bloating, tightness, or pelvic heaviness, let us know. We adapt your routine: drink plenty of water, take gentle walks, avoid impact, wear comfortable clothing. And if the response is too fast or too slow, we readjust. The key is personalisation and listening.

Follicle size and timing of the egg retrieval: the role of the “trigger”

When several follicles reach an adequate size — in our clinical practice, around 18 mm — we schedule the ovulation trigger to induce final egg maturation. We use hCG (e.g. Ovitrelle®) and/or a GnRH agonist (such as Decapeptyl), depending on your profile and the risk of over-response.

We explain it like this: “When your follicles are around 18 mm, we administer the trigger and schedule the egg retrieval (pick-up) 36 hours later.” That interval is important so the eggs are ready. The egg retrieval is a short procedure under (light) sedation in which we aspirate the follicular fluid to collect the eggs. Our goal is to obtain the greatest number of mature eggs possible without pushing too hard. Afterwards, depending on your plan, we either vitrify or proceed to fertilisation (IVF/ICSI).

An honest reminder: not all follicles contain an egg and not all retrieved eggs will be mature or excellent; that is why we insist on preparing the cycle well and on setting a realistic egg target from the outset.

Protocols and medication: PPOS, GnRH antagonists and agonists

The “what and how” of medication depends on your reserve, age, medical history, and goal:

• GnRH antagonist protocols (short): widely used for their flexibility and lower risk of over-response. They allow the use of an agonist trigger when appropriate.
• GnRH agonist protocols (long): useful for certain profiles (endometriosis, need for fine LH control), but not suited to everyone.
• PPOS (progestin-primed ovarian stimulation): this is the protocol used most often at our clinic. A progestogen prevents a premature LH surge during stimulation. It does not involve a fresh embryo transfer: if suitable embryos are obtained, they are vitrified and transfer is planned in a later cycle.

Mild stimulation is a dosing strategy, not a separate protocol. It can be used with PPOS, an antagonist or an agonist. It uses lower doses than conventional stimulation for that profile and may be considered in selected cases; low ovarian reserve alone does not automatically make it the best option.

Gonadotropins (FSH/LH) are the engine; GnRH (agonist/antagonist) directs the traffic. Decisions are not dictated by milligrams but by your response. We prefer to explain every change transparently: “Today we are lowering the dose slightly to keep growth steady,” “We are adding the antagonist to prevent an LH surge,” and so on.

In cases of low response, besides fine-tuning, we discuss from the start the possibility of chaining a second stimulation (see next section) or luteal-phase stimulation, to reach the target egg number in the shortest possible time.

Side effects and real risks (OHSS, torsion, discomfort)

Most women experience mild discomfort: bloating, pelvic heaviness, mood changes, breast tenderness, or fluid retention. These are usually temporary and manageable with hydration, rest, and gentle activity.

Uncommon but important risks:

• Ovarian hyperstimulation syndrome (OHSS): today we prevent it very effectively by adjusting doses, choosing an agonist trigger, and adapting the plan. If you notice a very distended abdomen, intense pain, persistent nausea, or difficulty breathing, call us.
• Ovarian torsion (rare): the risk increases with significantly enlarged ovaries, which is why we advise against jumping, sudden twisting, or impact.
• Egg-retrieval complications (uncommon): mild bleeding, pelvic discomfort, or a very unlikely infection.

We prefer a safe stimulation over an aggressive one. More is not always better: the “sweet spot” is growing enough without compromising your wellbeing. We always personalise based on your characteristics and your goal — and we will explain every decision along the way.

Low response: strategies (dose adjustment, second stimulation in the luteal phase)

When the response is modest, the game is not over. We adjust doses, review adherence, consider adjuvants where appropriate and, if we discussed it with you from the start, we can chain a second stimulation cycle in the luteal phase (DuoStim) or wait for the following cycle. In our practice we put it like this: “If there is a low response, we can chain a second stimulation in the luteal phase to add eggs without waiting a full month.”

This approach is useful when time is a factor (age, work schedules, window of opportunity). The key is that you feel supported and that the decision is shared, with realistic expectations about the number of eggs we aim to reach.

Egg target and preservation: how many to vitrify according to your case

There is no universal magic number, but we work with targets. As a general guideline, at Love Fertility Clinic we aim to vitrify at least 10 eggs when the plan is to preserve for the future; we adjust that target for age and estimated egg quality. If you have a good reserve, sometimes we achieve it in a single stimulation; if not, we plan more than one cycle to reach the figure that maximises your future chances.

Why talk about targets? Because it organises decisions (doses, timelines, DuoStim yes/no) and prevents frustration. And because at the end of the process you will be able to say: “I have X vitrified eggs” — and with that, a realistic plan for when you are ready to use them.

Daily life during ovarian stimulation: do’s and don’ts (exercise, sex, travel, clothing)

Do:

• Walk, use a gentle stationary bike, stay hydrated, and prioritise rest.
• Wear loose, comfortable clothing; many patients thank us for the tip of wearing soft leggings during the last few days.
• Eat foods that are gentle on the abdomen (less salt if you are retaining fluid).

Better to avoid or limit:

• Impact exercise, jumping, intense running, and heavy weights, especially in the final week (enlarged ovaries mean a higher risk of torsion).
• Vigorous sex towards the end of stimulation (sensitive ovaries).
• Long trips just before the egg retrieval: they can complicate monitoring or the trigger/retrieval schedule.
• Excessive alcohol and tobacco: they interfere with egg quality and recovery.

And a practical reminder: warning signs to call us immediately (intense pain, very distended abdomen, repeated vomiting, breathing difficulties, heavy bleeding, or fever).

Frequently asked questions

Ovarian stimulation works best when it is yours, not “one-size-fits-all”: we study your reserve (AMH + AFC), set targets (for example, ≥ 10 eggs if you are preserving), choose the right protocol, and support you with monitoring, adjustments, and clear language: follicle ≠ egg, more is not always better, and your comfort matters. In selected cases, a second stimulation in the luteal phase may be considered to accumulate eggs; a low response alone does not make it necessary, and the outcome is not guaranteed. And if you want to start with certainty, book your Fertility Test: it is the roadmap that guides us.