Men were held responsible for the inability to have children in medieval times, a study of medical and religious texts found.
Some of these texts recognised the possibility of male infertility, making references to sterility and "unsuitable seed", and there were even records of a urine test to determine if a husband or wife was to blame for a lack of children.
Some medieval recipes to treat infertility in men were devised, including catmint-boiled wine and ground up pig testicles in wine.
The analysis of medical and religious texts from the 13th century, conducted by researchers at the University of Exeter, showed that some of the texts discussing male infertility were widely circulated.
According to the researchers, it's been widely assumed that women in medieval England were blamed for a couple not having children, and that religious preaching about infertility focused on women.
It's also been assumed that when men were considered responsible for a couple not being able to have children, it was because of sexual dysfunction, where the man was unable to have an erection and have intercourse.
Dr Catherine Rider, a historian at the University of Exeter involved with the study, said: "Although medical texts tended to devote most space to female infertility, male infertility was nonetheless regularly discussed as a possible cause of childlessness in academic texts and by educated medieval medical practitioners, and this information may have been used on occasion when treating childless couples.
"These books show people had accepted long ago that male reproductive disorders were not just about problems that occurred during sex."
Dr Rider found that doctors at the time recogniSed that sexually-active men might not be able to conceive a child.
In 13th-15th century England, male infertility was viewed as a possibility not only among people who studied medicine and could read Latin, but also among less-educated people who read English texts.
Latin texts were translated, adapted and added to, influencing English recipe collections which include infertility medicine concoctions.
For example, a 12th century gynaecological book called 'The Trotula,' written by an anonymous author, was circulated widely and translated into English and French.
It said that "conception is impeded as much by the fault of the man as by the fault of the women".
LESS VISIBLE FORMS OF STERILITY
The widely read book also described male reproductive disorders being about less visible forms of 'sterility' as well as problems relating to erections and sperm emissions.
The book also quoted an earlier book, saying: "Whether this comes about from a defect of the spirit impelling the seed, or from a defect of spermatic humidity, or from a defect of heat.
"If from a defect of heat, he will not desire intercourse…if it happens from defect of the spirits he will have no desire and he will not be able to have an erection….if it is because of a defect of the seed, when they have intercourse they emit little or no semen."
And men with excessively cold and dry testicles had seed that was 'useless for generation.'
The Trotula also included a urine test to see if a man or woman was responsible for the 'defect' - a test that was also included in previous medieval texts.
The remedy detailed that both the man and the woman should each urinate in a pot of bran, and the pots should be left for nine or ten days.
If worms appeared in one of the pots, than that person was the infertile partner.
Another medical text, written by John of Mirfield, a cleric associated with St Bartholomew's Hospital in London in the late 14th century, warned: 'It should be noted that when sterility happens between married people, the males are accused by many people of not having suitable seed,'
Some medieval medical books also had advice for men to improve their fertility.
For example, The Liber de Diversis Medicinis (Book of Diverse Medicines), a collection of medical recipes from the 15th century, said: 'If a man wishes that a woman will conceive a child soon take catmint and boil it with wine until it is reduced to a third of its original volume, and give it to him to drink on an empty stomach for three days.'
Another recipe book, located in the Wellcome Library in London, advised that to stop sterility, a person should: "Take a pig's testicles, dry and grind them, and give them to drink with wine for three days."
However, it wasn't clear if the man or woman was supposed to drink the remedy.
Through the analysis of these medieval texts, Dr Rider was able to uncover a much wider concept of male infertility than was recognized by medieval marriage laws.
These laws allowed marriages to be annulled due to sexual impotence, but not infertility.
Dr Rider also found evidence of men being accused of impotence in church courts, but medical ideas about male reproductive disorders went beyond the idea of just impotence.
"We can't fully understand what attitudes were like towards male infertility in the Middle Ages because we have so few records which describe the experiences of people who had reproductive disorders," Dr Rider said.
"It is hard to know whether men or women were more likely to seek treatment for infertility in practice.
Most of our evidence comes from doctors who discussed what might happen and how to treat these problems."