Source: DGNews  |  Posted 2 years ago

By Deborah Brauser

ATLANTA -- October 27, 2009 -- A treatment with low-dose metformin improves
pregnancy rates in patients who have repeatedly failed to conceive with in
vitro fertilisation (IVF), according to results from 2 studies presented here
at the 65th Annual Meeting of the American Society for Reproductive Medicine
(ASRM).

Masao Jinno, MD, Women’s Clinic Jinno, Choufu City, Tokyo, Japan, presented the
results of both studies on October 21. The studies enrolled women without
polycystic ovary syndrome (PCOS) undergoing IVF. These women had all had at
least 2 failed IVF procedures.

In the first study, 33 patients received metformin 550 mg daily for 8-12 weeks
before and during ovarian stimulation for IVF. The outcomes were then compared
with those found in the patients’ previous IVF procedures and those from
control patients matched by age, body mass index, and previous IVF failures.
Based on 9 insulin-resistance-related parameters, the investigators then
developed a discriminant score (DS) of 0.6647 to predict ongoing pregnancy
success. They found that the ongoing pregnancy rate was significantly higher in
the metformin-treated group than in the matched control group (30% vs 6.1%, in
33 cycles) or previous IVF data (1.9%, in 104 cycles).

Using the optimal threshold point from the DS, the researchers predicted
ongoing pregnancy in the patients treated with metformin with 0.90 sensitivity
and 0.91 specificity. This group also had significantly improved follicular
development and embryo quality.

In the second study, 199 women were randomised into 4 groups: those treated
with metformin who had a DS above (group 1, n = 18) and below (group 2, n = 80)
the optimal 0.6647 point and those not treated with metformin but with scores
above (group 3, n = 15) and below (group 4, n = 86) the set point. Group 1 had
a significantly higher rate of ongoing pregnancy: 56% versus 14%, 20%, and 15%
for groups 2 through 4, respectively.

“In summary, low-dose metformin improves the pregnancy rate in IVF repeaters,
probably by decreasing insulin resistance. Plus, its indication can be decided
by a DS calculated from 9 insulin-resistance-related parameters before
metformin administration,” reported Dr. Jinno.

“To my knowledge, this is the first report that shows the effectiveness of
metformin treatment for non-PCOS patients,” said Dr. Jinno. He added,
“Metformin can help 20% of IVF patients with repeated failures and without
PCOS. These patients are more commonly seen in clinical practice than PCOS
patients, so the results are practically very useful.”

Presentation title: Low-Dose Metformin Improves Pregnancy Rate in ART
Repeaters Without Polycystic Ovary Syndrome: Its Mechanism and Indication.
Abstract P-533