What is OHSS, and who is at risk?
Ovarian hyperstimulation syndrome (OHSS) is an exaggerated response to the hormone medications used in stimulation. The ovaries become enlarged, and blood vessels release fluid into the abdomen. That fluid shift causes the symptoms.
OHSS ranges from mild to severe.
- Mild OHSS is common. You feel bloated, mildly uncomfortable and a little nauseated for a few days after retrieval. It settles on its own.
- Moderate OHSS brings more bloating, abdominal pain, nausea and some weight gain from fluid. It is managed with rest, fluids and close follow-up from the clinic.
- Severe OHSS is uncommon. Large amounts of fluid can build up in the abdomen and sometimes around the lungs, and the blood can thicken. Rarely, it leads to blood clots, kidney problems or a hospital stay.
Moderate to severe OHSS occurs in roughly 1 to 5 percent of stimulated cycles overall.
In egg donors, severe OHSS occurs in under 1% of cycles, and blood clots are rarer still.
Who is at higher risk? Women who respond strongly to stimulation. That includes younger women, women with a high antral follicle count or a high AMH level, women with polycystic ovary syndrome (PCOS), and women who develop many follicles or very high estrogen levels during a cycle. Egg donors are young and screened for a good ovarian response, so as a group they are at higher risk than many IVF patients. That is why prevention is built into donor protocols.
How do clinics prevent OHSS in donors?
Clinics prevent OHSS at every stage of a donor cycle.
- Screening. The antral follicle count and AMH at the medical screen show which donors are likely to respond strongly.
- Dosing. The clinic sets medication doses to match the donor's expected response, aiming for a healthy number of eggs rather than the highest possible number.
- Monitoring. Bloodwork and ultrasounds during stimulation show how many follicles are growing and how fast estrogen is rising. The clinic adjusts doses as it goes.
- The trigger. This is the biggest change in donor care. Many donor protocols now use a GnRH agonist trigger, such as Lupron, instead of hCG. hCG stays in the body for days and keeps stimulating the ovaries after retrieval. A GnRH agonist trigger produces a short hormone surge that fades quickly, so the ovaries settle sooner. With a GnRH agonist trigger, moderate to severe OHSS in donors falls to under 1 percent. Read more about Lupron.
- No pregnancy in the donor's cycle. In a donor cycle, the embryos are not transferred to the donor. Pregnancy hormones can make OHSS worse, so this removes one of its drivers.
Because the embryos go to the intended mother or a gestational surrogate, the donor's own cycle can be planned around her safety first.
What are the risks of the retrieval procedure?
Egg retrieval is a short procedure, about ten minutes, under IV sedation. A thin needle, guided by a transvaginal ultrasound, passes through the vaginal wall into each ovary to collect the eggs. There is no incision. The risks are:
- Bleeding, from the ovary or the vaginal wall. Most is minor and stops on its own.
- Infection, in the pelvis. Some clinics give antibiotics to reduce the risk.
- Injury to nearby organs, such as the bowel, bladder or a blood vessel.
- Reactions to sedation.
Bleeding, infection and injury to nearby organs each occur in well under 1 percent of retrievals.
Ovarian torsion is a separate risk. It happens when an enlarged ovary twists on itself and cuts off its own blood supply. It is rare. It causes sudden, severe pain on one side and needs emergency care. You lower the risk by avoiding vigorous exercise during late stimulation and until your next period. The egg donor process page explains what to expect on retrieval day and during recovery.
| Complication | Approximate frequency | Warning signs | Prevention | Who covers treatment |
|---|---|---|---|---|
| Mild OHSS | Common | Bloating, mild discomfort | Dosing and monitoring | Intended parents |
| Moderate to severe OHSS | Severe: under 1% of donors; blood clots rarer still. Moderate to severe: about 1 to 5 percent of stimulated cycles overall | Rapid weight gain, severe bloating, nausea or vomiting, shortness of breath, reduced urination | Screening, dosing, monitoring, GnRH agonist trigger | Intended parents and donor complication insurance |
| Bleeding after retrieval | Well under 1 percent | Increasing abdominal pain, dizziness, fainting | Ultrasound guidance; clotting checked at screening | Intended parents and donor complication insurance |
| Infection | Well under 1 percent | Fever, worsening pelvic pain, unusual discharge | Sterile technique; antibiotics at some clinics | Intended parents and donor complication insurance |
| Injury to nearby organs | Well under 1 percent | Severe pain, blood in urine, fever | Ultrasound guidance | Intended parents and donor complication insurance |
| Ovarian torsion | Rare | Sudden, severe one-sided pain, nausea | No vigorous exercise until the next period | Intended parents and donor complication insurance |
| Medication side effects | Lupron: about 20% of donors; bloating and cramping from FSH are common | Hot flashes, trouble sleeping, mood changes, headaches, bloating, cramping | Correct injection technique; dose adjustment | Intended parents |
What side effects do the medications cause?
The stimulation medications cause side effects in most donors. They are usually mild and go away after the cycle.
- Bloating and a feeling of fullness, as the ovaries enlarge.
- Breast tenderness.
- Mood changes, such as irritability or feeling tearful.
- Headaches and tiredness.
- Bruising, redness or soreness where you inject.
- Mild pelvic discomfort, especially late in stimulation.
About 20% of donors have side effects from Lupron, which some protocols use to prevent early ovulation: hot flashes, trouble sleeping, mood changes and headaches. FSH, the main stimulation hormone, causes bloating and cramping. Tell your clinic about any side effect, even one that seems minor. Full detail is on the medication side effects page.
Does egg donation affect future fertility or cancer risk?
Future fertility. Studies to date have not shown that egg donation lowers a donor's future fertility. In a normal month, your body brings one egg to maturity and the rest of that month's group is lost. Stimulation matures more of that same group. It does not take eggs from future months, so you do not run out of eggs sooner.
Two caveats. A serious complication, such as a severe infection or a torsion that damages an ovary, could affect fertility. That is rare, and it is why prevention matters. And long-term data on donors who have cycled several times are limited.
Cancer risk. Researchers have studied whether fertility medications affect the risk of breast, ovarian or uterine cancer. Studies so far have not shown a clear link for donors, but long-term research focused on egg donors specifically is limited. If you have a personal or family history of cancer, discuss it with your clinic and a genetic counselor before you donate.
A cancer risk from donation is theoretical and has not been proven. Because long-term data are limited, PLS follows the ASRM-aligned limit of no more than six donations in a lifetime.
What emotional risks should donors consider?
Egg donation also has emotional sides that are worth thinking about before you start.
- Hormone-related mood changes during the cycle.
- Genetic offspring. Children may be born who are genetically yours. You may never meet them, or, under a known or identity-release arrangement, you may.
- Future contact. Consumer DNA testing means no donation is reliably anonymous for life. A child, or a relative of a child, could find you through a DNA match.
- Your own family. You may want to think about how you would explain donation to a partner or your own children later.
- Disappointment. A cycle may produce fewer eggs than hoped, or no pregnancy may follow. That is not your failure, and your compensation does not depend on it.
That is why every donor has a psychological evaluation with a licensed mental health professional before a cycle. It is a chance to talk through these questions with someone who works only for you. See egg donor screening for what the evaluation covers.
Who pays if a complication happens?
The intended parents. Your donor agreement should say so in writing.
- Medical care during the cycle, including monitoring, retrieval and follow-up, is paid by the intended parents.
- Donor complication insurance is purchased by the intended parents before stimulation. It covers treatment for complications from the cycle, such as OHSS or a retrieval complication. The policy is listed in your donor agreement.
- Your own attorney reviews the agreement so that coverage is clear before you sign.
If a complication happens, call the clinic the same day. Do not wait to see whether it gets better. Keep the PLS egg donor coordinator informed as well, so that the insurance and payment side is handled while you focus on getting well.
The complications insurance policy for PLS donors has a $250,000 benefit. On the 2023 schedule, which PLS is updating, it cost the intended parents $385. The policy term and exclusions are to be confirmed.
Sources
- American Society for Reproductive Medicine (ASRM), practice committee guidance on prevention and treatment of ovarian hyperstimulation syndrome, and on oocyte donor safety.
- Society for Assisted Reproductive Technology (SART).
- US Food and Drug Administration (FDA), donor eligibility rules (21 CFR Part 1271).