Sentence:  In the study group ll patients <WSD>aborted</WSD> spontaneously between the 17th and 20th gestational week and 8 patients <WSD>aborted</WSD> after the 21st week. 
Meaning of the word marked with <WSD> tags:  To miscarry; to bring forth (non-living) offspring prematurely. (First attested in the mid 16th century.)