A Spanish study compared the mental health of parents who had had twins with those of parents who had had just one baby. The study looked at those parents who had had twins 'naturally' and those who had had twins as part of an assisted-conception process. After birth the fathers of twins had more depression, anxiety, social dysfunction and sleeping problems than fathers of one baby. However, the mothers of babies produced by assisted conception had fewer symptoms of depression before birth than the mothers of twins conceived spontaneously, perhaps because they had had more counselling preparing them for having twins.
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