Definition - What does High Responder mean?
A high responder is a woman who has a significantly high ovarian reserve and will eventually produce a surplus of follicles in response to the ovarian stimulation used in in vitro fertilization (IVF). High responders are at risk of developing ovarian hyperstimulation syndrome (OHSS) and producing aneuploid embryos (embryos carrying an abnormal number of chromosomes).
FertilitySmarts explains High Responder
The risk factors for OHSS in high responders include:
- Polycystic ovary syndrome
- Ovarian hyperthecosis
- Age below 30
- Body weight
- Excessive number of follicles produced or large quantity of eggs retrieved
- High or steeply rising levels of estrogen prior to an hCG trigger shot
- Previous episodes of OHSS
- High doses of hormonal medicines used to stimulate ovaries and produce follicles
The IVF stimulation protocol in a high responder needs to be tailored according to individual characteristics. The following individualized controlled ovarian stimulation strategies can prevent OHSS in high responders:
- Cancellation of the IVF cycle and withholding the hCG trigger shot
- Coasting, which is stopping the gonadotropin injections for a few days and deferring the hCG trigger shot until the estrogen levels drop. This, in turn, decreases luteinization (process of production of a yellow mass from the follicles), which lowers the levels of a protein that triggers OHSS
- Reducing the dose of hCG trigger shot
- Freeze-all cycle: Freezing all embryos before transfer can improve chances of implantation
If the above methods are not used to prevent OHSS, high responders are likely to achieve a chemical pregnancy (positive beta hCG pregnancy test, followed by a subsequent failure of the pregnancy to progress). Although embryos produced by high responders are at risk of aneuploidy, a study revealed that the number of euploid (normal) embryos multiplies as the number of eggs retrieved after ovarian stimulation increases.