Women wanting to become pregnant once sought out the waters of "fertility towns" like Bath, Tunbridge Wells and Wellingborough. Did these women know something we've long forgotten?
The name "Red Well" appears often in the Northamptonshire town of Wellingborough.
It features on a pub, a school, a leisure centre and a doctor's surgery.
It was its Red Well that made once made Wellingborough, along with Bath and Tunbridge Wells, nationally famous for its waters - which many believed could boost fertility.
Wellingborough attracted King Charles I and his consort Henrietta Maria, while Queen Mary was wooed by the hot springs of Bath during the 1700s (and became pregnant 10 months after). Catherine of Braganza, the wife of King Charles II, visited Tunbridge Wells in 1662.
And where the royals went, others (if they had the means) followed, says Dr Jennifer Evans, author of Aphrodisiacs, Fertility and Medicine in Early Modern England.
In the 17th Century, "taking the waters" was part of a "multi-stranded" fertility improvement regime, which also often included aphrodisiacs, medicine and cooking recipes.
Infertility, says Dr Evans, was seen essentially as a lack of the required body heat in the 17th Century.
Treating fertility involved warming the body - hence the hot waters of Bath.
There is no data available from the 17th Century to prove whether the method actually worked.
However, it was widely noted at the time that those toiling the soil in the countryside were more fertile than the upper-class town and city dwellers.
This, says Dr Evans, triggered "a panic about urban upper-class fertility" in the 18th Century. An upper class living on a protein-rich diet and largely idle, came to see the rural workers as "more godly" and in "better health".
Add to that the fetid water, open sewers and general squalor of the 17th Century urban environment and it is not difficult, says Dr Marie-Ann Ha of Anglia Ruskin University, to see how a season spent in the countryside, imbibing mineral waters and eating various vegetables and herbs would have benefited both health and fertility.
Fertility boosters of the 17th Century
- powdered womb of a rabbit
- animal testicles
Source: Dr Jennifer Evans, University of Hertfordshire
Dr Ha, a senior lecturer in public health, said: "Having clean water would have made a really big difference. Even now we have laws that there must be at least two doors between your kitchen and your toilet."
Good nutrition, healthy living and weight control play an important role in giving people the "greatest chance of conception", she said.
And while there is no data to prove the efficacy of taking the waters, there was plenty of anecdotal evidence it worked.
Dr Robert Peirce, for example, wrote in his Bath Memoirs: or Observations in Three and Forty Years at the Bath what Cures how he helped married women conceive.
He tells of a Mrs Hawkins of Marlborough who by the age of 40 had "never been with child". It took "much bathing, which she patiently endured" but she went on to "have five children at some years distance".
In the case of Wellingborough, local history expert and borough councillor Jon-Paul Carr believes the Red Well's fertility reputation might stem from the water's high iron content.
Henrietta Maria first came to Wellingborough in 1627 and made a number of repeat visits during the 1630s.
She went on to have nine children, says Mr Carr.
"The story goes that she used to keep a medicine chest by her bed that was full of all different waters from around the UK, including the waters of Wellingborough.
"We like to think that the Wellingborough waters aided fertility and helped her succeed in getting pregnant nine times over."
But what of today? Do these old fertility towns still have their powers?
It is difficult to say, according to Dr Ha, not least because how many babies women have is determined less by health than - with the availability of contraception and fertility treatments - the choices couples make and their social background.
The district of Bath and North East Somerset has one of the lowest fertility rates in England and Wales, ranking 329th out of 346 areas in 2014. The borough of Tunbridge Wells does not fare much better, ranked 256th out of 346.
Wellingborough, however, is a different story.
Since 2001, the borough of Wellingborough has jumped from the 78th to the 17th most fertile part of England and Wales last year, with the borough's women having on average 1.77 children in 2001 and 2.12 in 2014.
But the town's meteoric fertility rise is unlikely to be down to its Red Well, high iron content or not, says Mr Carr.
It is more likely, according to the Office of National Statistics, to be a mixture of immigration of women from outside the UK, who tend to have a higher fertility rate, and more women in their 20s, 30s and 40s deciding to have children.
After its successful role in promoting royal progeny, the waters famed for "keeping the bowels open and quickening the pulse" were pumped down to the Dulleys Brewery, which made a tipple called Red Well Stout in its honour.
That brewery went out of business in the 1920s and the once famed Red Well now sits beneath a housing estate.