Is mild ovarian stimulation effective for IVF in women that are poor responders?

This study investigated mild ovarian stimulation (OS) for in vitro fertilization (IVF) in women with poor response. They found that there was no difference in outcomes between conventional and mild OS in these women.

Controlled ovarian stimulation (COS) is an assisted reproductive technique (ART). It is performed prior to in vitro fertilization (IVF). COS involves taking drugs to stimulate ovulation. Oocytes (eggs) mature in follicles. These follicles then release oocytes into the uterus. Oocytes are harvested for IVF. 

COS is not always straightforward. Some women do not respond well to COS. These women are called poor responders (PRs). Higher doses of drugs are usually used in these women. This leads to increased costs. It can also lead to more side effects. Some studies suggest that mild stimulation (MS) for IVF could be useful in PR women. Recent studies show that MS has similar fertility outcomes to conventional stimulation (CS). Others suggest MS may be more effective. It is unclear if MS is associated with better fertility outcomes compared to CS PR women undergoing IVF. 

This study analyzed 14 trials evaluating MS in PR women. Patients were treated with MS or CS. There are several COS protocols that can be used. The type of COS protocol varied across the studies. The main fertility outcome evaluated was the live birth rate (LBR). The clinical pregnancy rate (CPR) was also compared.

Four clinical trials with 1057 women evaluated LBRs.There was no significant difference in LBRs between MS and CS across studies. Six studies with 1782 women evaluated ongoing pregnancy rates. There was no difference in ongoing pregnancies between MS and CS. CPRs were also similar in MS and CS-treated women.

All studies reported the number of oocytes retrieved. Fewer oocytes were retrieved with MS. However, the proportion of high-quality embryos obtained was similar in both groups. 

The authors concluded that MS may be similarly effective as CS for IVF in PR women.

Couples with any cause of infertility were included in the study. It is unclear if MS may be more effective in certain conditions. More studies are needed. 

If you have any concerns regarding infertility and ovarian stimulation please consult with your doctor.