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A psychiatrist testified Friday that she warned Andrea Yates not to have any more children after she tried to commit suicide twice within months of having her fourth child in 1999.

But despite the warning, Yates had her fifth child in late 2000. The next June, Yates drowned 6-month-old Mary, 2-year-old Luke, 3-year-old Paul, 5-year-old John and 7-year-old Noah in the bathtub.

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Starbranch said Yates suffered from postpartum psychosis, which she said causes a mother to have delusions and lose touch with reality, making it much more severe than postpartum depression, from which millions of new mothers suffer.

"I could pretty much predict that Mrs. Yates would have another episode of psychosis," Dr. Eileen Starbranch told jurors in Yates' murder retrial.

Yates is being tried again in the drownings of her children in June 2001. An appeals court overturned her 2002 capital murder conviction because erroneous testimony might have influenced the jury. She has again pleaded not guilty by reason of insanity.

Yates' attorneys have never disputed she killed the youngsters but say she did not know at the time that it was wrong.

Prosecutors say Yates' actions belie those claims. They say she planned the drownings for a time when she would be alone with the children, after her husband went to work and before her mother-in-law arrived. Then Yates called police and later told a detective she had killed them because she was a bad mother and wanted to be punished, according to trial witnesses.

Starbranch said she treated Yates after she tried to kill herself by overdosing on sleeping pills in June 1999.

About a month later, Starbranch said, Yates's then-husband, Rusty, told her that Yates had held a knife to her own throat the previous day, and he disarmed her.

Starbranch said Yates had a bald spot on her head from scratching it, had not been taking her antipsychotic medication, had filthy hair and was unable to function. Starbranch said she sent the couple immediately to a mental hospital so Andrea Yates could be admitted.

Under cross-examination, Starbranch acknowledged that the words "filthy" and "catatonic" were not in her notes and said that Yates' nervousness and anxiety may have been a sign that she simply did not want to be at a psychiatrist's office. But Starbranch maintained that Yates was psychotic and not lethargic or exhausted from caring for four young children.

Over the next two weeks or so while hospitalized, Yates steadily improved while on antipsychotic drugs, Starbranch said. She saw Yates again several more times until early the next year, when Yates said she had stopped taking any medication because she was better.

But then in March 2001, Rusty Yates called Starbranch's office trying to make an appointment, saying his wife was getting worse since having the couple's fifth child in November, Starbranch testified.

"I knew that was a very ominous sign ... that lives were at stake, so I asked that she be brought in immediately," Starbranch said.

The couple never showed up, but Starbranch later learned that Yates was admitted to another mental hospital, the psychiatrist testified.

Yates, who is being tried in only three of the children's deaths, will be sentenced to life in prison if convicted. After the first jury rejected execution, prosecutors could not seek the death penalty again because they found no new evidence.