A Finnish court was on Tuesday due to hear a sexual molestation case against a doctor who says he sucked a patient's nipple to diagnose a medical problem in accordance with an old midwives' trick.

Lower courts earlier ruled that the doctor had not committed a crime, but the prosecution and the patient appealed against the judgement to the Finnish Supreme Court.

The 20-year-old woman went to the doctor in 2007 for an ultrasound breast exam and told the doctor some fluid had seeped from the nipple.

After obtaining her permission, he used his mouth to suck her nipple in order to taste the fluid, the doctor testified in court earlier.

While several medical organisations in Finland have questioned the practice, the district and appeals courts ruled that given the patient's consent, there was not enough evidence to prove that this particular unorthodox procedure was inappropriate.

The hearing was due to start later Tuesday.

- Sapa-AFP