NL 2015/01

Kyusaku Ogino: Think Backwards But Count Forwards. The Japanese Gynaecologist Died 40 Years Ago (01. 01. 1975)

The Japanese gynaecologist Kyusaku Ogino is normally mentioned together with Hermann Knaus, who are to thank for the Knaus-Ogino method of contraception. However, the two men worked independently.

By the time they finally met, each of them had independently informed the medical community, which was sceptical at first, of their groundbreaking discoveries. Knaus was at the University of Graz, Ogino was the head physician at Takeyama Hospital in Japan’s harbour city of Niigata. Ogino began his research before Knaus, in May 1919, and approached the issue from the opposite direction: he used the observations he’d made as a gynaecological surgeon to closely inspect the ovaries, the Fallopian tubes and the corpus luteum in various phases, while Knaus based his conclusions on physiological differences in the uterus’ behaviour over the course of the menstrual cycle.

Ogino’s objective was determining the days of fertility and infertility in the menstrual cycle. He was very familiar with the German literature, in which a number of completely contradictory theories were laid out. Into the 20th century, German was the main language of medicine in Japan, and even medical reports were written in German with Latin script. Ogino also had a helper for understanding these works, the German missionary Hubert Reinirkens.

Ogino was frustrated by the widely divergent information provided by German scientists: how could he advise married couples who were impatient to have a baby, or the opposite, who didn’t want a child, or another one? When would ovulation most likely happen? One author claimed it was between the seventh and fourteenth day of the menstrual cycle, another said the fourteenth and sixteenth day, and a third posited day 18.9. Over three years, Ogino closely observed 65 women with different but regular menstrual cycles and evaluated the data. First, he tried to establish a connection between the date of ovulation and the previous menstruation. Unfortunately, no pattern could be found. Then he counted in the opposite direction – and suddenly, it all fell into place.


No-one understands Japanese!

In February 1923, he published a short paper in Hokuetsu Medical Journal: “Ovulation is linked to the succeeding and not the preceding menstruation, as medical authorities have claimed.” And he also named a concrete time period for ovulation: 12 to 16 days before the beginning of menstruation, regardless of how long the menstrual cycle lasted. Other doctors were not impressed.

One year later, Ogino presented the details of his results – 92 pages of text plus five with photographs – in Japan Gynecological Journal, and this time, Japanese colleagues reacted with enthusiasm. Because he had successfully found a definitive answer to the discussion concerning the days a woman could get pregnant, ending it once and for all, the Japan Society of Obstetrics and Gynecology even gave him an award. However, the results of his research never made it to the USA or Europe.

Over the next few years, Ogino wrote a total of 26 papers on his revolutionary discovery in Japan, making him quite famous in that country. Not until 1928 did he visit Germany, and in 1930, Ogino published his data and findings in the German gynaecological journal Zentralblatt für Gynäkologie. With the aid of his calculation system, Ogino was able to interpret the other researchers’ data and determine why they had achieved incorrect results. The big names, including Hermann Knaus, congratulated him.


Days count rather than weeks

From Ogino’s observations, Knaus learned that “calculation of the menstrual cycle on the basis of weeks is imprecise and misleading, and the duration of the menstrual cycle should always be calculated in days.”

How do the two men’s results differ? Knaus: “Without a doubt, Ogino’s accomplishment is pointing out, before I did, the presence of the woman’s infertility during the menstrual cycle with certainty. But since less knowledge about the physiology of reproduction was available to him, he put much more generous limits around the dates of ovulation and conception than I did in 1929, on my own and independently of him.”

Although we’re aware, thanks to Ogino and Knaus, that menstruation is the result of ovulation, and not the reverse, the backwards calculation was solely of theoretical value. There was one thing Ogino and Knaus didn’t change: “...for the purpose of avoiding uncertainty with regard to calculating the duration of the menstrual cycle ... continuing to designate the beginning of menstruation the first day of the menstrual cycle and adhering to calculation of the cycle’s length in terms of the progression of time, as previously.”


H. Knaus, “Die periodische Frucht- und Unfruchtbarkeit des Weibes”, Zentralblatt für Gynäkologie 57, 24, 1933


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