THERE are two things for which my generation should nightly give thanks: peace and sex. Quite who we should thank for 50 years without a major war is not clear but we know who was responsible for the second - the scientists who created the oral contraceptive for women.

Sex was not invented with the Pill but it was finally freed from its oppressive association with child-bearing. It is hard now to think ourselves back to a time when married women recoiled from the embrace of their husbands because they feared the damage another child would do to their precarious family finances and to their bodies. The mother of five who dreaded her man coming home drunk because he might insist on his conjugal rights and create a sixth child is not a fictional creation of socialist playwrights.

The male prophylactic certainly reduced the likelihood of getting pregnant but it depended on being prepared. It also depended on the attitude of men, and many were reluctant to use the foul-smelling rubbers. It was not until the 1980s, when HIV persuaded condom-makers to present their products as flavoured, coloured, or oddly contoured fun items, that the rubber finally shed its negative image.

It is also hard to think ourselves back to a time when a reckless act of lust and the roulette wheel of chance could easily force two young people (and their unwanted offspring) into a dismal union that would blight their entire lives.

Of course, the Pill could not stop people marrying in haste and regretting at leisure but it drastically reduced the frequency of ''shotgun'' weddings.

Sexual liberation has been a boon to us all but the Pill has also made a huge and often unrecognised contribution to gender equality. At its most basic, the Pill has allowed women to enjoy sex too. Some men fear female equality in sex as much as they fear it in the labour market. Some may make the more principled objection that allowing the other half of the population to also treat sex as a leisure activity will further debase an intimate act that should be more than casual rutting. Of course female sexual liberation has its excesses (just think of those women's magazine articles on Twenty New Ways to an Orgasm!) but women have as great a capacity as men - if not greater - to accept the gift of sensual pleasure without becoming thoughtless shag-crazy hedonists.

Less obvious but equally important is that the Pill reduced our reliance on what for most of human history were the standard methods of limiting family size: abortion and child neglect. In seventeenth century France, it was common for urban women to give their newborn children to ill-paid wet nurses in the countryside. Between half and three-quarters of those infants died of maltreatment or starvation. Moral puritans will be quick to point out that abortion remains distressingly common. True, but imagine how common it would have to be if we were as sexually active as we are without the Pill. And it was women, not men, who bore the weight of guilt that came with abortion.

But the greatest change wrought by the Pill has been in allowing the rhetoric of gender equality to become a reality. Women can now choose how many children to have and when to have them. They can construct their own preferred balance of paid work and motherhood. What was previously a lottery is now largely manageable.

As with every other technological advance, the Pill will be condemned by Luddites who attach it to a host of vices but no-one can gainsay its main consequence. What had been fate is now a matter of choice.

q Steve Bruce is professor of sociology at Aberdeen University