Big families were the norm half a century ago.
Dr Paul Tan, 75, who used to chair the Family Planning Association of Singapore, said couples were reluctant to practise birth control in the 1950s and 1960s.
Dr Tan, who joined the association in the mid-1960s, said: "Women were not very educated then and they felt their job was to please their husbands."
Some also felt that with more children, they were considered more fortunate as they would have more family members to care for them in their old age, said the father of three grown-up children.
Hence, many families had at least five or six children then. Some even gave birth to a dozen or more kids.
Dr Tan, a retired gynaecologist who is now working as a locum general practitioner, added: "When you asked them how many children they have, some even had to count using their fingers."
In September 1965, the Government announced its five-year family planning scheme in the light of a rapidly growing population.
The Government also took over the association's family planning work, after the non-profit group asked it to do so.
The Government set up a Family Planning and Population Board to carry out family planning activities.
Under the government scheme, seven types of family planning methods, such as birth control pills, condoms and intrauterine contraceptive devices, were provided at subsidised rates.
Before the Government entered the picture, a group of women set up the Family Planning Association of Singapore in 1949.
One of the association's pioneers, Mrs Constance Goh Kok Kee, saw how many families had many children and some could not afford to feed them.
So the association went about teaching women about the need for birth control and dispensed contraceptives.
In those days, rumours that taking contraceptive pills made you sterile or would cause you to lose your sex drive were rife, said Dr Tan. Hence, birth control was not popular.
Dr Tan said: "People would not believe us, despite what we would tell them (about birth control)."
It was only in the later decades when Singaporeans became better educated - coupled with the Government's family planning policies - that family planning took off here, he said.
He added that the association, which is now known as the Singapore Planned Parenthood Association, is also a pioneer in providing sexuality education.
"Back in the 1980s, sex was a taboo subject. But premarital sex was quite rampant and teens were going for abortions. They were getting information about sex from all the wrong places," he said, of the need for sexuality education.
"Even my nurses used to scold me, thinking we were teaching kids how to have sex.
"We explained to them that sex education is more than talking about the sexual act. It's also about teaching birth control, the emotional and other aspects of sex and sexuality," Dr Tan said.