Sex drug finally helps them to start family
IT manager Christopher Lee, 42, and his wife had put off starting a family until about two years ago.
"We wanted to make sure we had the means to support a family first, so we threw ourselves headlong into our careers," he says.
As age was fast catching up, the couple, who had been married for about eight years, decided it was time "to make babies".
"I had just turned 40 and although she is younger - in her 30s - her fertility is also falling," he says.
By then, Mr Lee had been promoted and was given greater responsibilities at the office. He was also spending longer hours at work.
"All that and the stress of trying for a child took a toll on me. I found it difficult to get intimate with my wife. And when it came to the crunch, I could not maintain an erection," he recalls.
"What was to have been a beautiful intimate time with my wife became an ordeal. We were often frustrated and I felt I was constantly letting her down," Mr Lee adds.
This went on for "a couple of months" before the Lees decided to address the issue.
They did not want the option of in-vitro fertilisation (IVF) "as it could get really expensive".
"Seeing that I was the problem, I allayed her fears by taking it upon myself to seek help. So I went to see our family doctor, who referred me to a urologist," Mr Lee said.
He was put through a battery of tests and was told there was no problem with his fertility.
"I was happy when they told me I wasn't shooting blanks... I was merely not able to hold up the barrel," Mr Lee says, laughing.
He was prescribed Viagra.
"There was no immediate effect. It was only after the second month that things got better," he recalls.
And in the third month, his wife called to say they "needed to talk".
"She sounded serious and I was worried. Then I saw a series of pictures of pregnant women's baby bumps and babies that she had tagged me in on Facebook. Then I knew... We were having a baby," he says.
Their son is now 18 months old.
"I was over the moon when she gave birth. To think, when we were having issues, I never saw a way out.
"Who knew a little pill that had a whole lot of bad press was my way out," he adds.
Mr Lee is continuing with his use of sildenafil to "continue to have a normal sex life with my wife".
"I am also hoping for more children, perhaps a little girl next," he says.