CONTEXTO DE LA INTERVENCIÓN 31

Many studies have sought to identify the impact of maternal depression upon the mother-child interaction. This interest is probably influenced by the reported high incidence of the conditions. It has been established that 10 to 15 per cent of women are clinically depressed in the first three months after childbirth (Kumar and

Robson, 1984). Little is known about the incidence of postnatal depression by ethnicity, though a recent national UK survey identified higher rates of general depression among ethnic minority women (Meltzer, G i l , Petticrew and Hinds,

1995).

Depressed mothers are reported to act more negatively towards their infants and toddlers, to be less responsive (Bettes, 1988; Cox, Puckering, Pound and Mills, 1987), to be more critical (Webster-Stratton and Hammond, 1988) and to be more hostile (Lyons-Ruth, Zoll, Connell and Grunebaum 1986). Infants o f depressed mothers perform worse on object concept tasks, are more insecurely attached to their mothers and more frequently at 18 months show mild behavioural difficulties (Murray, 1992) than infants of non-depressed mothers. In addition, mother-infant interactions at 19 months seem to include less effective positive components and less mutual

responsiveness if the mother has suffered depression during the first year (Stein, Gath, Bucher, Bond, Day and Cooper, 1991).

Face-to-face interactions of depressed mothers and their infants have been compared to the interactions of non depressed mothers and their infants (Field, 1984,

Bettes, 1988). Field reported that depressed mothers showed fewer positive facial expressions, more negative expressions, fewer vocalisations and looked at and touched their infants less. In turn, the infants of these depressed mothers' showed fewer positive facial expressions, fewer vocalisations, more gaze aversion, more protesting and lower activity levels. Field suggests that the depressed effect on these infants could be the result of the frequent exposure to their mothers depressed behaviours or the result of the minimal stimulation provided by the mothers.

Field also proposes an alternative interpretation: it is possible that these infants were depressed from birth. Mothers identified as depressed during pregnancy were noted to have infants that had lower activity levels and limited responses to social

stimulation during the Brazelton Neonatal Behavioural Assessment Scale (1979). At three months o f age, these infants still showed similar patterns o f responsiveness; demonstrating fewer contented expressions and fussier behaviour during their interactions. Because the mothers' depression had continued postpartum, they were less active with their infants and showed fewer positive facial expressions, less imitative behaviour and less game playing with their infants. It was not clear whether the infant's depression was merely a behavioural style that persisted from birth or one that developed from prolonged exposure to the mother's depression, but these infants continued to interact in a depressed behaviour even when their mothers did not behave in a depressed fashion.

Cohn, Matias, Tronick, Connell and Lyons-Ruth (1986) identified that depressed mothers have a more intrusive interaction style. They report that the infants o f depressed mothers’ are more responsive to their mothers negative behaviour, while the infants o f non-depressed mothers are more responsive to their mothers' positive behaviour.

A study by Weismann and Paykel (1982) found the children o f depressed mothers were more likely to be the recipient of the hostility and irritability than the husbands, other relatives or associates. Mothers of pre-school children showed the greatest impairment in communicating with their children, in showing affection to them, and in responding to their signals. They were also less likely to stimulate the child and to engage in less varied play.

Whereas many studies have investigated parenting problems associated with

diagnosable clinical depression (see reviews o f clinical depression and parenting by Downey and Coyne, 1990; Gelfand and Teti, 1990), Fox and Gelfand (1994) point out that fewer studies have focused on parenting in a potentially much larger group: mothers who have depressive symptoms but are not clinically depressed by DSM- III-R standards (American Psychiatric Association, 1987). Information on the adjustment of children with clinically depressed parents whose disturbance is less severe is needed, as is an understanding o f the environmental and family factors that may exacerbate the risk of adverse consequences for some children (Downey and Coyne, 1990). Kuiper, Derry and McDonald (1982) suggest that any greater than normal degree of depressed or dysphoric mood may affect cognitive fimctioning.

Depression and stress typically co-occur in samples of clinically depressed mothers and are not easily disentangled (Coyne and Downey, 1991). Depressed mothers characteristically have little social support, unhappy marriages and temperamentally difficult children (Coyne, 1990; Teti and Gelfand, 1991). Mothers under stress interact less sensitively and responsively with their infants than less stressed mothers (Cox et al, 1987). How much parental depression itself accounts for parenting

problems is unclear and Rutter and Quinton (1984) implicate stress alone, finding no additional ill effect from depression. If there is a consensus, it is that parenting problems and child psychological disorders relate largely to more global features such as the severity and chronicity o f the parent's disorder, whatever the disorder type, and to the family's stress level (Goodman, 1992).

Although the evidence for an association between maternal depression and maternal responsiveness is not conclusive, those studies that have focused particularly on general mother-infant interaction during the first year typically have identified an association between maternal psychological state and the less than optimum mother- infant interactions.

Hellin and Waller (1992) looked more specifically at the association between feeding practice and depression during pregnancy. They found that mothers who scored highly on the Beck Depression Inventory (Beck, 1978) during pregnancy were more likely to report physical difficulties when breast feeding their infants and to give up breast feeding sooner than women who were not depressed. Hellen and Waller's conclusion indicated that for this thesis, there should be an assessment of the psychological state o f the participating mothers.

Harris and Macdonald (1992) found feeding problems in the child were related to high anxiety levels in the parent. Where parental anxiety was high, parents were more likely to use coercive or forceful management techniques to get the child to eat and children were more likely to show negative behaviour at mealtimes. Harris and Booth (1992) report that the consequence of this type of interaction, where the infant's signals of satiety are ignored by an anxious parent, then the strength o f such signals will be increased by the infant. This escalation of refusal behaviour will lead to screaming, vomiting and head turning.

The measurement o f depression in ethnically diverse populations is also particularly contentious because the cultural expression of syndromes may differ, or cluster in different ways in different cultures (Katon, Kleinman and Rosen, 1982, Littlewood and Lipsedge 1982, Sashidaran, 1986,). In recognition of these concerns, particular attention was paid to the choice of measures to be included.