A doctor accused of molesting and raping a 23-year-old woman during her two visits to his clinic in 2015 said he would not have entertained the idea because he knew she had a genital infection.

The woman, now 26, told the High Court last week that Wee Teong Boo, 67, had told her to take off her shorts and underwear during a medical examination and subsequently raped her in the early hours of Dec 31, 2015. Wee denies her claims.

He explained that he had diagnosed the woman with a lower tract genital infection and suspected both urinary tract infection and pelvic inflammation during her visits.

He said: "How would that arouse me? I'm a professional, (the thought) doesn't even cross my mind. The whole episode is very unfair to me."

According to Wee, the woman, then 23, had complained of gastric reflux, frequent urination and a cough. Wee said he asked her to proceed to the examination room, where he performed a check on her abdomen. Wee, a doctor for 40 years, said she then "caught (him) off-guard" by telling him "out of the blue" that her genitals were also suffering from an itch. He suspected pelvic inflammation and asked her if she would like to have her genitals examined, which she agreed to.

After seeing some redness and discharge, Wee also asked if he should do a pelvic examination and she agreed. Wee inserted two of his fingers into the woman's vagina and she felt no pain or discomfort. He prescribed her medication and their session ended.

Asked if he was wearing gloves during the pelvic examination, which is common practice, he said: "I was not wearing anything on my hands."

When questioned why, Wee said he "did what (he) did without thinking" as the hour was late and he had two other patients who were agitated waiting outside. He also did not use lubricant on the woman before the examination.

The court also heard the woman was given a queue number of 20 but had skipped the queue as patients with queue numbers 18 and 19 did not respond when called. These patients were upset when they found out that the woman managed to see Wee before them.

In his testimony, Wee - who is married with five children - also said he went for a full body check-up with a urologist of his own accord following the rape allegations as he had been suffering from issues of erectile dysfunction.

He said: "I'm not impotent, but it takes a longer time for me to achieve erection." He explained that he did not seek help earlier as he "was not bothered by it before and still (is) not bothered by it now".

He added that he was diagnosed with an enlarged prostate and lower than normal levels of testosterone in 2016.

Wee, who was told by Justice Chua Lee Ming several times to listen to the questions asked, repeatedly described his situation as "absurd" and "serious". He was also called out by Justice Chua for writing the operating hours of his clinic on his palm during his testimony without prior permission from the court. Witnesses are not allowed to refer to unauthorised notes during their testimonies.

The prosecution is expected to cross-examine Wee when the trial continues on May 24 and 25.