Most IVF side effects are short-lived and manageable: bloating, breast tenderness, headache, fatigue, and mood swings each affect roughly 10–60% of patients during stimulation, and serious complications are rare. The one to know about is ovarian hyperstimulation syndrome (OHSS), which affects about 1–14% of cycles overall and under 2–3% in severe form.
On the long-term side, cohort studies covering more than 1 million women show no meaningful increase in breast cancer risk and at most a small increase in ovarian cancer risk, concentrated in women who never gave birth.
Data in this article comes from the CDC National ART Surveillance System, ASRM patient education materials, peer-reviewed cohort studies (the Dutch OMEGA cohort, the Danish DANAC II cohort, and the Israeli Maccabi cohort) and four pooled meta-analyses, and FDA medication package inserts on DailyMed, compiled by the ProIVF Medical Editorial Team and reviewed by the ProIVF Medical Advisory Board.
IVF Side Effects at a Glance
The table below lists the typical side effects and frequency at each stage of a cycle, from stimulation through the long term.
| IVF stage | Common side effects | Typical frequency |
|---|---|---|
| Daily stimulation injections | Injection-site redness, bloating, breast tenderness, headache, fatigue | 10–60% each |
| Trigger shot | Bloating, nausea, mood changes | 30–50% with hCG (human chorionic gonadotropin) trigger |
| Egg retrieval (same day) | Mild cramping, spotting, sore throat from the breathing tube | Most patients, resolving in 1–3 days |
| Post-transfer / progesterone support | Bloating, constipation, fatigue, breast tenderness, mood changes | 10–60% depending on progesterone form |
| Long term (months to years) | No increased breast cancer risk; small possible ovarian cancer increase in some groups | See below |
Call your clinic immediately if you notice: rapid weight gain (more than 2 kg / 4–5 lbs in 2–3 days), severe abdominal pain, severe nausea or vomiting, shortness of breath, or clearly reduced urination — these are OHSS warning signs.
What Side Effects Happen at Each Stage of IVF?
1. During Ovarian Stimulation — Days 2–14
Stimulation medications — follicle-stimulating hormone (FSH) drugs such as Gonal-F, Menopur, and Puregon — raise estrogen levels quickly, and most short-term symptoms come from that hormonal shift.
| Side effect | Approximate rate | When it appears | What helps |
|---|---|---|---|
| Injection-site redness or swelling | 30–50% | Immediately after injection | Rotate sites, ice before and after, massage gently |
| Bloating and abdominal fullness | 40–60% | Days 6–10 of stimulation | Mild is normal; track your weight daily |
| Breast tenderness | 20–30% | Days 3–5 | Supportive bra; resolves after retrieval |
| Headache | 10–25% | Any time | Acetaminophen preferred; avoid ibuprofen during stimulation |
| Fatigue | 30–50% | Throughout stimulation | Expected; most pronounced in the final days |
| Mild fluid retention | 20–40% | Late stimulation | Normal physiological response |
Why ibuprofen is avoided: NSAIDs (nonsteroidal anti-inflammatory drugs) may interfere with follicle development by inhibiting prostaglandins. Use acetaminophen for headache or fever unless your clinic advises otherwise.
2. The Trigger Shot
The trigger shot — hCG (Ovidrel, Pregnyl) or a GnRH (gonadotropin-releasing hormone) agonist (Lupron, Decapeptyl) — finalizes egg maturation 36 hours before retrieval.
- hCG trigger: bloating, breast tenderness, and mood changes in roughly 30–50% of patients. hCG carries a higher OHSS risk, so clinics switch high-risk patients to a “dual trigger” or a GnRH agonist trigger.
- GnRH agonist trigger (Lupron): hot flashes, headache, and nausea in about 15–30%; these are temporary and carry a lower OHSS risk. Lupron’s specific profile is covered in our Lupron for IVF guide.
3. Egg Retrieval Day
The procedure takes 15–30 minutes under sedation, and same-day effects are usually mild cramping, spotting, and tiredness that resolve within 1–3 days.
- Mild cramping and pelvic pressure (most patients, resolving in 1–3 days)
- Light vaginal spotting for a few days
- Sore throat from the breathing tube used during sedation
- Fatigue for the rest of the day — plan to rest
Serious complications — bleeding, infection, or ovarian injury — occur in roughly 0.2–2% of retrievals.
4. Post-Transfer and the Two-Week Wait
After embryo transfer, progesterone support keeps the uterine lining receptive, and the side effects depend heavily on which progesterone form you use.
| Progesterone form | Side effects | Rate |
|---|---|---|
| Vaginal gel or suppository (Crinone, Endometrin) | Vaginal irritation, increased discharge | 10–20%; generally well tolerated |
| Intramuscular injection (progesterone in oil) | Injection-site pain, sterile abscess, soreness | 15–30%; higher blood levels but more local effects |
| Oral (less commonly used in IVF) | Drowsiness, dizziness | 30–60% |
Bloating, constipation, fatigue, breast tenderness, and mood changes are common at this stage regardless of form; management details are in our progesterone shot guide.
“Weigh the daily injection pain against the reassurance of stable levels — but know that a manageable side effect is never something to endure silently. Tell your nurse; in 20+ years of practice the fixes are almost always simple: warm the oil, slow the injection, rotate the site.” — Reproductive medicine specialist, ProIVF Medical Advisory Board, on managing IVF side effects, 2025
Which Side Effects Come From Which IVF Medication?
Each drug class has its own signature pattern — FSH drugs drive bloating and fatigue, antagonists cause mostly local skin reactions, and hCG triggers carry the highest OHSS-related symptom load.
| Medication | What it’s for | Common side effects | Notes |
|---|---|---|---|
| FSH drugs (Gonal-F, Menopur, Puregon) | Follicle growth | Bloating, headache, fatigue, injection-site reactions | 10–60% per symptom |
| GnRH antagonists (Cetrotide, Ganirelix) | Prevent early ovulation | Local skin reaction 10–15%, nausea 5–10%, rare allergic reaction <0.1% | See Cetrotide guide |
| GnRH agonists (Lupron) | Pituitary down-regulation or trigger | Hot flashes, headache, mood changes; more pronounced at higher doses | See Lupron guide |
| hCG trigger (Ovidrel, Pregnyl) | Final egg maturation | Bloating, nausea, mood changes 30–50% | Higher OHSS risk |
| Progesterone (Crinone, PIO, Endometrin) | Luteal support | Bloating, constipation, drowsiness, injection pain | Depends on form |
| Estradiol (Estrace) | Endometrial lining | Nausea, breast tenderness, headache, bloating | See Estrace guide |
If you are weighing whether these symptoms are worth it, our pros and cons of IVF article lays out the full trade-off.
Are There Long-Term Side Effects of IVF?
“Long-term IVF side effects” usually means cancer risk, and three population cohorts covering more than 670,000 treated women plus four meta-analyses now give a clear answer: breast cancer risk sits at or barely above parity, and the ovarian cancer signal is confined to women who never gave birth.
Breast cancer: no meaningful increase. The Dutch OMEGA cohort followed 25,108 IVF patients for a median of 21 years and found a standardized incidence ratio (SIR) of 1.01 against the general population (95% confidence interval [CI] 0.93–1.09) and a hazard ratio (HR) of 1.01 (0.86–1.19) against subfertile women who never had IVF — van den Belt-Dusebout et al., JAMA, 2016. Meta-analyses agree: 25 studies with 617,479 women pooled to an odds ratio (OR) of 0.97 (0.90–1.04) — Cullinane et al., BJS Open, 2022 — and 8 IVF cohorts with 746,455 participants pooled to a relative risk (RR) of 0.89 (0.79–1.01) — Li et al., International Journal of Gynecological Cancer, 2013.
A ratio of 1 means equal risk in both groups, so those are near-null results. The one cohort that did find more cancers is Danish: 61,579 ART-treated women versus 579,760 untreated women of similar age produced HR 1.14 (1.12–1.16), rising to 1.37 (1.29–1.45) for women starting treatment at 40 or older — Vassard et al., Human Reproduction, 2021.
Its comparator was the general population rather than other infertile women, which is probably why the Israeli Maccabi cohort — which also matched ART patients against non-ART fertility patients — found no increase (HR 1.10, 0.94–1.28 versus the general population; HR 1.00, 0.86–1.16 versus fertility patients) — Machtinger et al., Human Reproduction, 2022. ASRM’s patient fact sheets explain this safety data in plain language.
Ovarian cancer: a small signal, mostly in women who never gave birth. The Dutch OMEGA follow-up compared 30,625 ART-treated women with 9,988 subfertile women who never had ART, over a median of 24 years and 158 invasive ovarian tumors: risk was raised against the general population (SIR 1.43, 1.18–1.71) but not against the subfertile comparison group (HR 1.02, 0.70–1.50), and it did not rise with more cycles — Spaan et al., Journal of the National Cancer Institute, 2021.
Borderline ovarian tumors were the exception — SIR 2.20 (1.66–2.86) and HR 1.84 (1.08–3.14) — but with no dose-response across cycle number either, which is why the authors asked for caution in reading them as caused by stimulation.
Endometrial cancer: no clear increase. The same cohort found 137 endometrial cancers across 24 years — SIR 1.19 (0.97–1.44) against the general population and an adjusted HR of 1.11 (0.74–1.67) against non-ART women — with risk driven by obesity and endometriosis rather than by treatment, and no rise with more cycles or longer follow-up; the cohort was still young at the end of observation, with a median age of 56 — Spaan et al., Human Reproduction, 2025.
Other cancers: the 8-cohort meta-analysis found all-site cancer RR 0.99 (0.74–1.32) and cervical cancer RR 1.07 (0.45–2.55), while a 28-study update reported ovarian RR 1.33 (1.05–1.69) and cervical RR 0.67 (0.46–0.97) — directions that disagree with each other, and a reminder of how small these signals are — Chen et al., Critical Reviews in Oncology/Hematology, 2024.
The psychological side effects are real. IVF-related distress is among the most under-discussed impacts of treatment, with studies comparing its effect on certain quality-of-life domains to that of a cancer diagnosis. For the emotional side, our what happens to your body after failed IVF article covers recovery, and our IVF success stories article shows what the data actually says about your odds.
How Do You Manage the Most Common IVF Side Effects?
Seven practical habits cover most of what patients experience, from daily weight tracking to acetaminophen choices.
- Track your weight daily during stimulation and for a week after retrieval. A gain of more than 2 kg (4–5 lbs) over 2–3 days together with abdominal pain is the earliest OHSS warning sign.
- Hydrate with electrolytes when bloated; drinking large amounts of plain water alone can worsen the fluid shift.
- Rotate injection sites, ice before and press gently after, to reduce bruising and lumps.
- Use acetaminophen for headaches and avoid NSAIDs (ibuprofen, naproxen) during stimulation.
- Plan rest after retrieval — take the day off and do not drive for 24 hours after sedation.
- For progesterone constipation: add fiber, consider a clinic-approved stool softener, and avoid straining.
- Tell your care team about mood changes — they are common and manageable, and support groups and counseling help many patients.
Patient Stories: Three Different Paths
The following patient stories are shared with consent. Names and identifying details have been changed to protect privacy.
Case 1: Elena, 34 — Mild Side Effects, No Surprises
Elena, 34, had one fresh cycle in New Jersey with mild side effects only, and her transfer resulted in a live birth at a total out-of-pocket cost of $4,800 after insurance.
Elena, 34, did one fresh cycle in New Jersey. “I expected the bloating to be worse than it was. What actually got me was the fatigue — by day nine I was asleep by 8:30 every night,” she said. She tracked her weight daily (no rapid gain), used ice on injection sites, and managed headaches with acetaminophen. Her retrieval went smoothly, and her transfer resulted in a live birth. Total out-of-pocket after insurance: $4,800.
Case 2: Mei, 31 — Bloating and Mood Swings That Resolved After Retrieval
Mei, 31, has polycystic ovary syndrome (PCOS) and was at higher risk for OHSS, so her clinic used a GnRH agonist trigger to reduce that risk.
“I gained 3 pounds in the last week of stimulation and felt like a water balloon,” she said. “The mood swings were the part nobody warned me about — I cried at a supermarket commercial.” Her symptoms resolved within days after retrieval, and her single frozen transfer led to a pregnancy.
Case 3: Priyanka, 39 — Injection-Site Pain With Progesterone in Oil
Priyanka, 39, in Illinois, used intramuscular progesterone for luteal support.
“The shots were the hardest part of the whole cycle — sore lumps that lasted a week,” she said. Her nurse taught her to warm the oil, use a smaller needle, and massage the site afterward. She completed 8 weeks of PIO without infection, and her cycle ended in a live birth; the techniques her nurse used are in our progesterone shot guide.
FAQ
Q: What are the most common side effects of IVF?
Bloating (40–60%), fatigue (30–50%), injection-site reactions (30–50%), breast tenderness (20–30%), headache (10–25%), and mood changes. Almost all resolve within days of stopping the medications or after egg retrieval.
Q: Do IVF side effects last a long time?
Most short-term side effects resolve within 1–2 weeks after retrieval. Progesterone-related symptoms last through the 2-week wait and, if you become pregnant, can continue for several more weeks.
Long-term risks — mainly cancer — are small and extensively studied, with no meaningful increase in breast cancer risk.
Q: What are the long-term side effects of IVF injections?
The main long-term question is cancer risk: the Dutch OMEGA, Danish DANAC II and Israeli Maccabi cohorts, plus meta-analyses pooling more than 600,000 women, found no meaningful breast cancer increase (SIR 1.01; pooled OR 0.97, 95% CI 0.90–1.04).
Ovarian cancer shows a small signal (SIR 1.43, 1.18–1.71 against the general population) that disappears against a subfertile comparison group (HR 1.02, 0.70–1.50), and endometrial risk tracks obesity and endometriosis rather than treatment (adjusted HR 1.11, 0.74–1.67).
Q: How common is OHSS, and how do I know if I have it?
OHSS affects about 1–14% of cycles overall and under 2–3% in severe form. Warning signs: rapid weight gain (more than 2 kg in 2–3 days), severe abdominal pain, nausea or vomiting, shortness of breath, and reduced urination.
Contact your clinic right away if you notice any of these.
Q: Can I take painkillers during IVF?
Acetaminophen is generally fine for headaches and mild pain; avoid the 2 most common NSAIDs — ibuprofen and naproxen — during stimulation, because they may interfere with follicle development.
Ask your clinic about the 2-week wait too; most prefer acetaminophen there as well.
Q: Does IVF cause weight gain?
IVF causes temporary fluid retention and bloating, especially during stimulation and on progesterone; a study of 22,106 antagonist stimulation cycles found an average gain of 0.64 ± 1.64 kg during treatment, usually temporary — Elder et al., American Journal of Obstetrics and Gynecology, 2026.
See our IVF weight gain guide for the full breakdown.
Q: Do IVF medications cause mood swings?
Yes, and it is under-discussed: rapid estrogen shifts across the 10–14 day stimulation window affect neurotransmitters, making mood swings, irritability, and low mood common during stimulation and the luteal phase.
They usually resolve after treatment ends; if low mood persists, tell your care team — counseling and support groups help.
Q: Are IVF side effects worse with certain medications?
Generally, hCG-based triggers cause more bloating and higher OHSS risk than GnRH agonist triggers, with mood and bloating symptoms in 30–50% of patients; intramuscular progesterone causes more local injection pain than vaginal forms; and Lupron at down-regulation doses produces more hot flashes and mood effects. Drug-specific details are in our Lupron, Estrace, and progesterone guides.
How to Prepare for IVF Side Effects
A short preparation checklist covers the practical, medical, and emotional dimensions before your cycle starts.
- Stock the practical basics before the cycle: ice packs, a notebook or app for daily weight and symptom tracking, and your clinic’s after-hours number.
- Know your personal risk profile — PCOS, high anti-Müllerian hormone (AMH), age under 35, or a high follicle count all raise OHSS risk. Ask whether a GnRH agonist or dual trigger suits you.
- Plan time off for retrieval day, with help arranged for the next day if possible.
- Build the emotional side into the plan — line up a partner, friend, or support group in advance.
- Keep perspective with data. Most side effects are temporary and manageable. For the full picture of what IVF involves — costs, success rates, and the process — start with our IVF cost guide and hospital directory.
This article was written by the ProIVF Medical Editorial Team and reviewed by the ProIVF Medical Advisory Board. It is based on the primary sources linked throughout — government surveillance data, professional society patient education, FDA-approved medication package inserts, and peer-reviewed cohort studies — to provide objective, accurate information for patients.
Medical disclaimer: This content is for informational purposes only and does not constitute medical advice. Side effects vary by individual and by protocol; always discuss your specific symptoms with your fertility clinic.
Last updated: August 31, 2026
