At Metro Health Medical Center, Dr. Gerald Maloney wouldn't discuss the women's conditions in detail but said they were being evaluated by appropriate specialists.

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Besides exhaustion, there are biological reasons why some women don't return to their previous sex lives after childbirth, said Dr. Irwin Goldstein, director of sexual medicine at Alvarado Hospital in San Diego, California.

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The study didn't include any women, making it difficult to know if a similar association exists, Dr. Stevens points out.

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