Anthony Zimmerman

How Ogino Discovered Rhythm

When Doctor Kyusaku Ogino (pronounced Oh gee no) of Niigata, Japan, began his prospective study in May 1919, women had little to go by to ascertain the fertile days of their cycles. Popular opinion, even medical text books, were practically advising that pregnancy can occur on any day of the cycle, right up to the next menstruation. Contemporary studies in Germany, however, were excitedly proposing new theories about a fixed and limited time of fertility only once during the cycle. Unfortunately they disagreed. Ruge II concluded that ovulation occurs on days 7 -14 of the cycle; F raenkel, on days 14-16 (of regular 28 day cycles); Schroeder, on day 18.9 in average. So the spread was from the 7th to the 19th days and beyond, almost the entire cycle. Little of that helped couples who sought either to conceive or to avoid conception by natural ways. Dr. Ogino decided to do research of his own at Niigata University Hospital, where he was on duty to perform gynecological operations. He sensed something amiss in the German studies; they counted days of the cycle from the previous menstruation to locate the day of ovulation and the fertile time. Maybe that was a mistake. A German missionary priest, Fr. Hubert Reinirkens, helped him with his German studies. He selected 65 cases during his three year study of May, 1919 November, 1922. He included only those women who claimed very regular or almost regular cycles. He did not mind whether the cycles were long or short, so long as they were quite regular. One of them had 45-day cycles, another 40 days; 27 had 30-day cycles, 11 had 28 days, 3 had 23 days, others were somewhere between. Dr. Ogino marked it all down. The first thing he examined after incising the abdominal wall was the condition of the ovaries on both sides. Before disturbing them by traction, he inspected whether the one or the other ovary had a follicle which was not yet ovulated; and if so, what was its condition. If already ovulated, he observed the condition of the corpus luteum. He was aware that traction during the operation might alter the initial condition; ripening follicles might burst, and corpus luteums