Evaluating natural cycle IVF for older women with poor ovarian response

This study compared two types of IVF (in vitro fertilization) procedures for older women with a poor ovarian response. This study found that modified natural cycle IVF was promising, but not more effective than conventional IVF in older women with POR.

In vitro fertilization (IVF) is a method to treat infertility in which eggs are removed from the woman, artificially fertilized, and implanted into the uterus. Collecting eggs requires stimulating the ovaries using high doses of hormones. This process is called high-dose ovarian stimulation (HDOS). HDOS can cause side effects and has a risk of overstimulating the ovaries. Some women also do not respond well to HDOS and produce few eggs. This is called a poor ovarian response (POR).

Modified natural cycle IVF (MNC-IVF) is a gentler treatment where the egg is selected and matures under the woman’s natural hormone cycle. This is easier on the body and is thought to produce a single higher-quality egg. MNC-IVF has good pregnancy rates for younger women who respond well to IVF. Whether this treatment is also effective in older women is unclear.

This study looked at records from 476 women over age 40 with POR. 189 underwent HDOS-IVF (HDOS group). 287 women underwent MNC-IVF (MNC group). All patients had their treatment chosen by their doctor. Women in the MNC group had significantly lower anti-Mullerian hormone levels before treatment compared to women in the HDOS group (0.3 ng/mL vs. 0.6 ng/mL). This indicates that these patients had fewer eggs and lower fertility.

Significantly fewer patients in the MNC group had at least one high-quality embryo compared to the HDOS group (83% vs. 94%). However, significantly more patients in the MNC group had 1 embryo transferred compared to the HDOS group (93% vs. 37%).

After treatment, significantly fewer patients in the MNC group had a positive pregnancy test compared to the HDOS group (5% vs. 19%). At 10 weeks, significantly fewer patients in the MNC group were still pregnant (2.6% vs. 10%). Only 3 patients in the MNC group had a successful birth compared to 23 patients in the HDOS group.

Certain factors were associated with a higher chance of a continuing pregnancy. Treatment with HDOS-IVF increased the odds of a continuing pregnancy by 2.56 times compared to MNC-IVF. Having at least one high-quality embryo significantly increased the odds of a continuing pregnancy by 5.25 times.

This study found that MNC-IVF was promising, but not more effective than conventional IVF in older women with POR. However, the authors suggest that MNC-IVF is more patient-friendly, especially for women who do not want to undergo egg donation.

This study was retrospective, meaning it looked back in time to analyze data. Patients had their treatment decided by their doctor, which may bias the results. Larger studies are needed to confirm these results.

Talk to your doctor about your treatment options.