Abstract
Background
Our previous randomized controlled study showed that the complete abortion rate in
termination of pregnancy up to 63 days with the combined use of letrozole for 3 days
followed by vaginal misoprostol was significantly higher than that of misoprostol
alone. A positive correlation was observed between the basal estradiol level and the
failure rate. We performed this pilot study to assess if a longer course of letrozole
followed by misoprostol would improve the estradiol suppression and the complete abortion
rate of pregnancy up to 63 days.
Study Design
Twenty subjects requesting legal termination of pregnancies up to 63 days were recruited.
Medical abortion was offered with letrozole 10 mg daily for 7 days followed by vaginal
misoprostol 800 mcg on the 7th day.
Results
Median induction-to-abortion interval was 7.5 h (range, 4.75–10.75 h). Overall complete
abortion rate was 95%. All subjects with gestation ≤49 days (12/12) as well as 87.5% of subjects with gestation between 50 and 63 days
(7/8) had complete abortion. No major adverse event were reported and over 88% of
women would like to have medical termination as an option should it be required in
the future.
Conclusion
This pilot study showed that a 7-day course of letrozole followed by vaginal misoprostol
was associated with a very high complete abortion rate (95%) which is comparable to
the standard regimen with sequential use of mifepristone and misoprostol in medical
termination of early pregnancy up to 63 days.
Keywords
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Article info
Publication history
Published online: June 20, 2012
Accepted:
May 11,
2012
Received in revised form:
April 25,
2012
Received:
April 12,
2012
Identification
Copyright
© 2012 Elsevier Inc. Published by Elsevier Inc. All rights reserved.
