Boiled catnip taken on an empty stomach for three days could help, or a delicious goblet of dried ground pig testicles mixed with wine: a new study of medieval advice on male infertility – and recipes to remedy it – suggests people were far less ready to automatically lay blame on the woman than had been assumed.

Catherine Rider, senior lecturer in medieval history at the University of Exeter and expert on medieval magic, medicine, religion and marriage, has studied popular texts in English from the period, as well as Latin texts aimed at the university-educated elite. She found a general understanding that male infertility could be responsible when a couple failed to produce a longed-for child. In the late 14th century John of Mirfield, who worked at St Bartholomew’s hospital in London and probably drew on much earlier texts, warned: “It should be noticed that when sterility happens between married people, the males are accused by many people of not having suitable seed.”

Rider, whose findings are published in the Social History of Medicine journal, believes that although historians have long been interested in the history of pregnancy and childbirth, infertility – particularly in the medieval period – has been much less studied. A widely circulated 12th century text on gynaecology, the Trotula, which was translated into both French and English, stated baldly: “conception is impeded as much by the fault of the man as by the fault of the women.”

The texts, she found, discussed both impotence – which was grounds for marriage annulment – and infertility.

“Defect of spermatic humidity”, or men with “excessively cold and dry testicles” could be the problem, and the Trotula included a test, reproduced by many later writers, to check whether the difficulty lay with the man or the woman. Both should urinate into separate pots of bran, which were then left for up to 10 days: the one in which the worms appeared indicated the infertile partner. If worms appeared in neither pot, neither was infertile and the couple could be helped by medicine.

Gilbert the Englishman, in his Compendium of Medicine complied in the the 1250s, considered “a defect in the operation of the generative members for the natural operation of the generative organs is lacking when the penis does not become erect or the seed is not emitted.” Three virtues were needed for the man’s organs to work properly, Gilbert explained: heat from the liver, spirit from the heart and moisture from the brain. “We have found others who have desire in the liver. These neither erect the penis nor emit seed.”

The unfortunate woman might recognise some of these problems by experiencing “something like a flame of fire in the womb” or “something like ice in the womb”. Bernard of Gordon also suggested an alarming remedy for a man with a short penis: “it should be beaten gently with rods, and plastered with pitch”.