Early pregnancy failure is a common condition, affecting 15% of all clinically recognized pregnancies. There are three possible management approaches in case of early pregnancy failure: expectant management, surgical intervention, and medication treatment. [1,2,[3], [4]].

Medicational treatment offers more control over the timing of tissue passage compared to expectant approach and is highly effective [5,6]. General risks of medication management include retained tissue that requires surgical evacuation (8-9%), blood transfusion (2%), and pelvic infection (less than 1%) [7].

In recent decades, Misoprostol, a prostaglandin E1 analogue, has become the most commonly used medical agent in the managing of early pregnancy loss [8]. Studies show treatment with Misoprostol is safe and effective in cases of missed abortion [9,10]. The success rate of Misoprostol, defined by evacuation of the pregnancy sac from the uterine cavity, is 80%-85% [11,12]. Side effects, such as nausea or diarrhea, are relatively rare with vaginal use [9]. Also, most patients report improved quality of life following medication [13]. It has also been reported that compared to surgical evacuation, Misoprostol treatment does not jeopardize the potential for future fertility and obstetric outcomes [14].

Updated data implies that in first- and second-trimester abortion, combined treatment with Misoprostol and Mifepristone is more effective than treatment with Misoprostol alone, and thus are considered the gold standard for medical abortion [15,16]. However, Misoprostol-alone regimens may be the treatment of choice in settings in which Mifepristone is not available or is too costly [15].

Misoprostol can be given by oral, sublingual, or vaginal administrations, while the dosage ranges from 100 to 800 micrograms, and has shown to reduce the need for surgical evacuation and shortens the time to complete expulsion, compared with placebo. The most suitable route and dosage of Misoprostol for missed abortion is not yet clear and remains a subject for debate [3,17,18].

In case of treatment failure after the first course of Misoprostol, a second course of Misoprostol may be administered. Information about the administration of a second dose of Misoprostol, although practically practiced frequently, has so far not been well investigated[19,20].

ACOG states that one repeat dose may be administered no earlier than three hours after the first dose and typically within seven days if there is no response to the first dose [18].

Therefore, the objective of our study was to assess the rates of success of the second dose of Misoprostol administration and to evaluate the parameters that may effect success rates.