Be honest, how effective do you consider crocodile dung would be as a contraceptive?

It's one of the less bizarre items in a new Radio 4 programme on the history of family planning.

Some of the lengths couples of the past went to to avoid unwanted pregnancies beggar belief.

Actually by 'couples' we mean 'women' - not much has changed there!

Here's our brief guide to the contraceptives of yesteryear.

Crocodile Dung

That's right - reptile droppings. Amorous Ancient Egyptian women used crocodile pooh pessaries. Documents dating back to 1850BC refer to this method of contraception. Crocodile dung is actually slightly alkaline, like modern-day spermicides, so it could have worked. On the other hand, it may well have been that after application neither party felt much like making love.

Honey

Things still hadn't got much better 300 years later for the poor old Egyptians. By 1550BC, records are referring to contraceptive tampons made from linen flax and soaked in a mix of honey and date paste. A tad sticky, we would have thought.

Mercury

Women in China 4,000 years ago drank mercury to prevent pregnancy. One key drawback of this innovative technique is that mercury is poisonous.

Jumping backwards

Soranus, the influential Greek gynaecologist of the second century, swore by an unusual contraceptive method. He advised women to jump backwards seven times. Imagine - after sex, rather than settling back into post-coital bliss, you have to leap out of bed and start making like Denise Lewis. Romantic? Astonishingly, Soranus was still regarded as something of a gynaecological whizz-kid well into the second half of the last millennium.

Sneezing

For centuries it was thought that violent sneezing would expel semen. Bless you.

Lemons

In many cultures, half a squeezed lemon was pressed into service as a diaphragm. The citric acid acts as a spermicide but the technique is not recommended if you are at all prone to little nicks or abrasions - ouch, that smarts! Lemons are still used in parts of Eastern Europe. It's not thought this is what was meant by the Bible's command to 'be fruitful'.

Early condoms

The first condoms - again, thanks to the ever-inventive Egyptians - were made of animal intestines. The legendary lover Casanova placed his faith in linen condoms and by the nineteenth century Japanese men were sporting 'kabutogata', hard sheaths made of tortoiseshell or leather. Presumably this led to some nasty chafing.

Wood

The block pessary was a wooden cube with concave sides. The theory was that, with a bit of luck and a lot of rummaging around, one of the concave surfaces would fit over the cervix. The device was favoured by the Victorians but was described in 1931 as 'an instrument of torture'.

Beavers

Women in north America sought to prevent conception by soaking dried beaver testicles in a strong solution of alcohol and then drinking deep of the resulting brew. Whether it was effective is not recorded - but it certainly kept the beaver population down.

From Crocodile Dung To Electrocution starts on Radio 4 on Monday, January 15 at 3.45pm.