A City lawyer drowned herself in the Thames after struggling with the conflicting demands of motherhood and her career, an inquest heard today.

Catherine Bailey, 41, a mother of three children, who killed herself six months after having her third child, may have been suffering from postnatal depression, a coroner said.

A partner in SJ Berwin specialising in banking and commercial law, Bailey had not long returned to work when she disappeared from her offices in January.

Her body was found near Richmond bridge, south-west London, the next day, half an hour after she sent an emotional text to her husband, Dr Neil Ashman.

It read: "Richmond. I am so sorry. BK [Big Kiss] all my love to you and the girls. Hold them close."

Coroner Alison Thompson told West London coroners' court: "It is probable she may have been suffering from a degree of postnatal depression. Ms Bailey was a very capable and professional woman and a loving mother of three young children who found it hard to meet the demands of motherhood and the high standard she had set herself.

"For whatever reason, she determinedly did this act. It is an absolutely tragic situation."

Ashman, a consultant kidney specialist who was joined in court by his wife's father as well as other friends and relatives, told the hearing: "We feel we have a sequence of events that led to her very sad death. We can't bring her back."

The coroner then said: "It was without warning?" Ashman replied: "Absolutely."

Detective Sergeant Bernard McCabe told the court that Ashman alerted them at about 6pm the day his wife disappeared.

His last contact with her was at lunchtime but he became increasingly concerned after calling her office and finding her not at work. Her bank records showed she had booked a room at the Thistle hotel at the Barbican in central London that night but staff there could not recall whether she had been there.

Police used analysis of her mobile phone and BlackBerry records to track her movements to the Embankment but could not find her.

The next morning, they traced her to Blackfriars station and then discovered she had travelled west.

Her husband, who believed she may have been heading for Kew Gardens in west London, as she had "enjoyed this area", alerted friends who helped police to search for her.

McCabe said Bailey spent Saturday afternoon in the Twickenham area but she was not seen again until her body was spotted floating in the river by an onlooker at around 5.50pm.

McCabe said: "She had a demanding job and the balance between that and three young children. It was the emotional trauma that appeared to have accumulated – going back to work after the birth of her three children.

"She was obviously a very professional and driven person."

Bailey, of Islington, north London, was born in Johannesburg and attended university in Cape Town, where her husband studied. She became a partner at SJ Berwin in 2003.

She had no history of psychiatric illness. The postmortem examination gave the cause of death as drowning and showed very small traces of alcohol, paracetamol and caffeine in her blood. The coroner recorded a verdict of suicide.

The couple's two older daughters are Inez, five, and Ruby, four.

Postnatal depression

• Around one in 10 women suffer from postnatal depression (PND).

• More than 50% of cases start within a month of childbirth, but it can start up to six months or even a year later.

• It is different from the milder "baby blues" which occurs in half of all new mothers on the third or fourth day.

• PND is a depressive illness characterised by feeling unhappy, irritable and helpless. It can be mild to severe. Symptoms include tiredness, sleeplessness, constant crying, eating too much or too little, and physical pains.

• Some cases can last less than three months, but 30%-50% may last more than six months.