1 Institute for the Study of Children, Families and Social Issues, Birkbeck College, University of London, 7 Bedford Square, London WC1B 3RA, 2 Royal Free and University College Medical School, University College, London NW3 2PF, UK, 3 Vrije Universiteit and 8 Centrum Medische Genetica, Brussels, Belgium, 4 The Fertility Clinic, Rigshospitalet section 4071 and 7 Department of Psychology, Play Therapy and Social Work, Rigshospitalet section 4074, Copenhagen University Hospital, Copenhagen, Denmark, 5 Sahlgrenska University Hospital, East, Goteborg, Sweden and 6 Unit for Human Reproduction, First Department of Obstetrics and Gynaecology, Aristotle University of Thessaloniki, Thessaloniki, Greece
9 To whom correspondence should be addressed. e-mail: jacqueline.barnes{at}bbk.ac.uk
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Abstract |
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Key words: ICSI/IVF/child behaviour/parentchild relationship/parenting
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Introduction |
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Studies performed so far into outcomes of ART have focused primarily on physical problems such as birth defects and neurodevelopmental outcomes (Bonduelle, 2003). Some studies have been performed looking specifically at childrens socio-emotional development, but have tended to be small samples (Mushin et al., 1995
; Gibson et al., 2000a
) and have not studied the newer types of IVF such as ICSI which, it could be argued, raise additional risks (Sutcliffe, 2000
, 2002) because the more invasive nature of the procedure may lead to extra stresses on the couples undergoing treatment. Questions have been raised about the physical and socio-emotional development of children born using this technique (Sutcliffe, 2000
) linked with possible strains on parents and their relationship with their children. Using this technique, particularly useful in the treatment of male infertility, a single sperm is selected and treated, then injected into an oocyte (Palermo et al., 1992
). There is less information about the children born following this method of assisted reproduction than other forms of IVF.
Potential sources of strain following a period of childlessness and then undergoing ART of any type include the failure to work through feelings towards infertility (Mushin et al., 1995). The child may be a constant reminder to one parent of their infertility, possibly acting as a narcissistic injury or creating asymmetry in the marital relationship (Colpin et al., 1995
). In most countries, ICSI has been used primarily for male factor infertility (Sutcliffe, 2002
), which could have specific implications for fathers.
A review of issues related to the development of IVF children (Van Balen, 1998) suggested that the main concerns are: the child might be seen as very precious and then be subject to overprotection; parents may have exaggerated expectations of their child; after a long period of infertility, parents may have difficulty adapting to the reality of child rearing; and the child conceived using IVF may be perceived as different by other people in the familys social network. Nevertheless, on the basis of the studies included in the review, Van Balen (1998
) concludes that no negative differences can be found in parentchild relationships or childrens psychological development. He remarks on the small size of most of the studies available, although this does not preclude the detection of clinically relevant differences.
Similarly, research into parentchild relationships in families who used IVF has not, by and large, confirmed the predictions of difficulties, although to date most studies have not included large samples. Mothers who became pregnant using IVF are generally reporting more pleasure in their children, more warmth towards them and more parental competence than naturally fertile mothers (Golombok et al., 1995; Van Balen et al, 1996
). An international study including children from Italy, The Netherlands, Spain and the UK (Golombok et al., 1996
) compared children conceived using either donor insemination (DI) or IVF with naturally conceived (NC) controls and adopted children, aged between 4 and 8 years. During in-depth interviews, mothers in both assisted reproduction groups and the adoptive mothers expressed more warmth about their child than mothers of NC children. The fathers in the IVF and DI groups were more involved and mothers reported less stress overall than mothers in the NC control group.
It has been suggested, however, that these results may be an indication of the tendency to report socially desirable responses (Colpin et al., 1995). Some detailed observational work in a small-scale study from Belgium found that, at 23 years, comparing only those mothers currently employed and who had used IVF were less able to allow their young children autonomy in a problem-solving task than mothers who had conceived naturally (Colpin et al., 1995
). However, a study conducted in Australia comparing 65 children conceived using IVF with 61 NC controls did not replicate these findings (Gibson et al., 2000a
). No differences were identified between IVF and comparison families in observed parentchild attachment, nor were any differences identified in maternal sensitivity, structuring or hostility during videotaped free play. However, this same group found that the IVF fathers expressed lower self-esteem and less marital satisfaction than those in the NC control group (Gibson et al., 2000b
), although measure of general adjustment and parenting showed no differences.
All the studies reported above have included IVF births, but in the last 10 years there has been increasing use of ICSI (Sutcliffe, 2000; Nygren and Nyboe Andersen, 2002
). Developed initially to address male infertility factors, it has been increasingly used for non-male factors where fertilization has failed with normal IVF. However, the implications of this newer technique for family relationships has not been fully investigated. It may have no impact, but there is a possibility that male factor problems may lead to more secrecy about disclosure and more marital discord (McWhinnie, 1995
). The potential for chemical and mechanical damage is greater using this technique, as is the likelihood of introducing foreign material into the oocyte. Some uncontrolled outcome studies have found a higher rate of sex chromosome abnormalities (Bonduelle et al., 1996
) or delayed development (Bowen et al., 1998
). Thus parents may be more anxious over time about children conceived using this method. Finally, it may have been used after traditional IVF, thus there could be a longer period of childlessness prior to conception. It is important to investigate both physical and emotional development of children born following ICSI, and the relationship between child behaviour and family characteristics, comparing them both with children conceived using traditional IVF and with NC children.
Here we present the results from a large-scale, multisite European study which was designed to compare ICSI conceived children with NC controls, and to examine the relative levels of stress in the family, as well as parental well-being and adaptation to their parental role, and the childrens socio-emotional development. A group of children conceived using traditional IVF was also included to determine any differences between the two ART groups. Including information from a number of countries, apart from increasing the sample size for the relatively new population of children conceived using ICSI, has enabled there to be an examination of effects on children and parents both within and across different cultures.
The aims of the study are to address the following hypotheses: (i) ICSI is associated with increased family stress and marital discord compared with families who have conceived naturally; (ii) parents who have conceived using ICSI have more mental health problems and difficulties in adapting to the role of parent than those who have conceived naturally; (iii) parents who have conceived using ICSI will report that their children have more psychosocial adjustment problems at the age of school entry than parents who have conceived naturally; and (iv) parents who have conceived using ICSI will be comparable with those who have conceived using IVF.
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Materials and methods |
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According to centre size, the aim was to recruit groups of ICSI, IVF and NC children with 175 children per group in Britain/Belgium and 66 children per group in Denmark/Sweden. The final totals were close to this (see Table I). Children were recruited so that at the time of assessment they would be between 4.5 and 5.5 years. Children were eligible if they were singleton, Caucasian, born after at least 32 weeks gestation, first or second born and whose mother tongue was respectively English, Dutch, Danish, Swedish or Greek.
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A comparison group of children conceived with standard IVF (i.e. without ICSI) was also recruited using the same criteria. The IVF comparison groups were recruited from participating fertility clinics in all countries in a similar manner to the ICSI conceived children.
NC controls were selected according to the above criteria and the groups were matched as closely as possible in each country to the ICSI and IVF groups for maternal age, maternal education and parental socio-economic status, gender and birth order. Due to differing national laws and quality of child health records, strategies for the recruitment of NC control and comparison groups differed from country to country. In the UK, Belgium and Greece, local schools and nurseries were used to recruit matched NC controls. In Sweden, NC controls were recruited via the Swedish medical birth registry. In Denmark, recruitment was from the participating hospitals birth registry. The participation rate (where known) is indicated in Table I. The different recruitment strategies used for each groups, and across countries, may have introduced some selection bias. The ideal situation would have been to have a national birth register in each country. In the absence of that resource, the control groups recruited in Belgium and the UK may have been biased towards children and families with few problems, or alternatively to those with many problems who wished to share these with a psychologist.
Procedures
Close to their fifth birthday, children received a paediatric examination and an assessment of their cognitive development using the WPPSI-R and subtests from the McCarthy Scales of Child Development (the results of medical and the cognitive testing are reported elsewhere; Kristoffersen et al., 2003; Sutcliffe et al., 2003
).
Children were also presented with a procedure designed to investigate their perception of parents, the BeneAnthony Family Relations Test (Bene, 1985). This test allows them to attribute 16 positive feelings [e.g. Who does (child) like to play with? Who smiles at (child)?] and 16 negative feelings [e.g. Who is naughty? Who makes (child) cry?] to their mother, father, siblings, themselves or to nobody in the family. An additional eight items reflect dependence [e.g. Who should help (child) get dressed in the morning?] giving a total score for each family member that can range from 0 to 40. The family members are represented by cardboard shapes attached to a posting box base into which each statement can be posted.
The countries used different strategies for this, some asking parents to complete the questionnaires at the same time as the child assessment, other countries using postal distribution and return. In all tables, the sample size is indicated together with the countries included in the analysis. The response rates of mothers and fathers in each country to the most frequently completed questionnaire [the Child Behaviour Checklist (CBCL)] are shown in Table I.
Parental well-being and family functioning
Measures were only included that assessed current well-being and family functioning. It would have been useful to include other instruments examining a history of mental health difficulties and family stresses (such as life events) during the 5 years since birth, but there was pressure to keep the number of questionnaires to a minimum. As an indication of current emotional well-being, parents completed the 28 item version of the General Health Questionnaire (GHQ; Goldberg and Hillier, 1979) describing four dimensions: somatic symptoms, anxiety, social dysfunction and severe depression, each with seven items (scored 0, 1, 2 and 3) with scores ranging from 0 to 21 and a total symptom score (range 084). Current stress regarding parenting was examined using the Parenting Stress Index (PSI), Short Form (Abidin, 1990
) which has a subscale indicating Parental Distress (PD) consisting of 12 items with a 5-point response scale (range 1260; e.g. there are quite a few things that bother me about my life).
Marital relationships were key to this study since some previous studies had found more discord in families who have conceived using IVF. The Dyadic Adjustment Scale (DAS; Spanier, 1976) measures the quality of the parental relationship. It has four subscales: consensus (range 065; e.g. agreement making major decisions); satisfaction (range 050; e.g. ever discussed divorce?); affectional expression (range 0 12; e.g. not showing love); and cohesion (range 0 24; e.g. share outside interests) and a total adjustment score (range 0151).
Undergoing ART involves a substantial commitment to becoming a parent. Measures were included to examine current commitment to parenting (range 17102; e.g. I cannot imagine a satisfying life without children) and (for most adults their other major role) to their identity as a worker outside the home (range 17102; e.g. I find that I put work responsibilities ahead of family responsibilities) (Greenberger and Goldberg, 1989). Each scale consists of 17 items with a 6-point Likert-type agree to disagree response scale. A higher score indicates more commitment.
Parentchild relationship
There have been suggestions of overprotection or higher levels of warmth in relation to IVF children. However, stress within the parentchild relationship is also relevant. The PSI has a ParentChild Dysfunctional Interaction subscale (P-CDI) derived from 12 items indicating difficulties in the parentchild relationship (range 1260) (e.g. my child smiles at me much less than I expected). The Parental AcceptanceRejection Questionnaire (PARQ; Rohner, 1999) asks parents how they usually treat their child and measures both warmth and negative aspects of the parentchild relationship. It consists of 60 items each with a 4-point scale (strongly agree to strongly disagree). Scores are derived for warmth/affection (range 2080; e.g. I say nice things about my child), aggression/hostility (range 1560; e.g. I nag or scold my child when he/she is bad), neglect/indifference (range 1560; e.g. I ignore my child) and rejection (range1040; e.g. I wonder if I really love my child). By taking the warmth score from 100, the four scales make up a total acceptance/rejection score, with higher scores indicating more rejection in the parentchild relationship.
Childrens socio-emotional development
To understand parenting, it is important to have information about the children themselves. While it would have been preferable to obtain this independently (for instance from teachers), this was not possible. Consequently, parents were asked to complete a personality or temperament scale, the McDevitt and Carey (1978) temperament questionnaire. The 72 items each have a 7-point Likert-type scale ranging from hardly ever to almost always which reflect how much the parent considers each of the behaviours is typical of their child (e.g. when my child objects to wearing certain clothing he/she argues loudly, yells and cries). Nine temperamental dimensions (activity, rhythmicity, approach, intensity, mood, persistence, distractibility, threshold and adaptability) are derived by taking the mean of the eight item scores for that dimension so that each dimensions score ranges from 1 to 7 and the total temperament score ranges from 9 to 63 (a higher score indicating a more difficult temperament).
The CBCL (Achenbach, 1991) gives information about childrens emotional and behavioural problems. Descriptions of 113 problems are presented and the parent indicates whether they are not true, somewhat or sometimes true or very true or often true of their child, with item scores of 0, 1 or 2. The total score (adding all items) is converted to a T score to normalize the distribution and to take into account child age (range 23100), with different conversion tables for boys and girls. The symptoms are subdivided further into externalizing problems (e.g. fights, temper tantrums) and internalizing problems (e.g. worries) which are also converted to normalized T scores, with a score of 50 representing the 50th percentile. A T score of 60 is at the bottom of the clinical range, with T scores of 64 or more representing marked problems.
The PSI Short Form (Abidin, 1990) Difficult Child (DC) subscale consists of 12 items (e.g. I feel that my child is very moody and easily upset) to which the parent has to agree or disagree (5-point Likert-type scale), resulting in a total difficult child score ranging from 12 to 60.
Statistical analysis
For each questionnaire, data were only included in the analysis if the total response rate for the country was at least 60%. In all countries, there were lower response rates for fathers questionnaires. In some cases, this led to severely reduced sample size for fathers since the countries with the largest samples (Belgium and the UK) had the lowest response rates. In these cases, to increase sample size, results are presented including countries with at least a 50% response rate.
Univariate analyses were conducted, using ANOVA in SPSS 11.5 for Windows, to determine differences in mean scores between the children conceived using ICSI, IVF and the NC controls. Where a group effect was identified post hoc at a significance level of P < 0.001, Tukeys test was conducted. The level of significance was chosen to take into account alpha inflation.
In those instances where there was a significant group effect on mean values at P < 0.001, linear regression analyses were conducted in SPSS 11.5, using the Enter method, to control for demographic differences between the conception groups. Dummy variables were created for each conception group, and the reference group was the NC controls. All the demographic descriptors for which there was a significant univariate conception group effect were included: maternal education, maternal age, paternal education and paternal age. Country was also entered along with childs gender if there was a significant difference between boys and girls on the outcome variable. The reference country was chosen for each regression as the one with the lowest score for the outcome variable under consideration.
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Results |
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Parental well-being and family functioning
There were no conception group differences in maternal well-being according to the GHQ total score or any of the subscales (see Table II). Furthermore, no group differences were identified in the total GHQ for fathers. Rates of problems on the subscales were generally low, the only difference being a conception group effect on social dysfunction (see Table II). However, this difference was not evident for either group in the regression analyses, after taking demographic factors and country into account (ICSI standardized = 0.09, t = 1.76, P < 0.08; IVF standardized
= 0.12, t = 2.38, P < 0.02).
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Mothers who had conceived using ICSI reported fewer negative feelings towards their children than mothers in the naturally conceived group (PARQ total) and were specifically less likely to report aggressive or hostile feelings (PARQ aggression; see Table V). There were no significant differences on the fathers responses to the PARQ (see Table V).
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On the basis of childrens responses to the BeneAnthony, there were no conception group effects for childrens positive or negative feelings towards or total involvement with either mother or father (see Table VI)
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The conception group effect remained for maternal commitment to parenting. Those mothers who had used ICSI had more commitment to their parental role than the NC group (adjusted R2 = 0.11, F = 6.76, P < 0.0001; ICSI versus NC standardized = 0.20, t = 4.94, P < 0.0001). In addition, there was a significant country effect, with mothers in Belgium and the UK reporting more commitment than those in Sweden (
= 0.27 and 0.13, t = 5.38 and 2.50, respectively). Parental age and education were unrelated.
Child personality and socio-emotional development
There were no significant conception group differences in total temperament of the children according to mothers or fathers (see Table VIII), nor were there any differences on the subscales. On the basis of the DC scale or the PSI, there were no significant differences between conception groups (see Table VIII ).
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Discussion |
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Parents of children born using both methods of assisted reproduction reported their children as having similar temperaments and similar levels of behaviour problems to the NC group.
Mothers (but not fathers) in the ICSI group were more committed to being a parent than the NC control mothers. Duncan and Edwards (1999) have identified three gendered moral rationalities used by women to explain their roles, based on identities and responsibilities to children: those who see themselves as primarily a mother; those who see themselves primarily as a worker; and those with an integrated motherworker role. The mothers who have experienced ICSI are closest to the primarily mother identity. This may indeed have some implications in years to come. Women who have negated their role in the outside world in order to commit to parenting may, as they see their chances of career development receding, regret this approach. Thus it is vital to follow these families as their children grow and the families have different priorities.
However, at this point in their childrens lives, there is no evidence of any resentment. The PARQ allows the respondent to report on the parentchild relationship, including a number of questions elicited. Using this, we are able to report that mothers who have used ICSI were less likely to be hostile or aggressive about their child than those mothers in the NC control group, although, in contrast to Golombok et al. (1995), we did not find higher levels of expressed warmth. Possibly, as Van Balen (1996
) suggests, they may be trying to be overprotective by suppressing negative feelings about their child, which might also have implications during adolescence, a time when children become more independent from their parents and may display a range of emotional and behavioural problems not typical of younger children. Following these and similar families over time will be required to address this issue.
Nevertheless, the limitations of the study need to be kept in mind. The variable, and low in some cases, response rate in each country for the questionnaires may have influenced the results. Families experiencing difficulties may have been less likely to complete the questionnaires, especially in the ART groups who have worked harder to become parents. Another possible factor which inevitably distorts the comparison is that the families who have conceived from fertility treatment implicitly represent the successful ones, i.e. the ones who have followed the stressful processes involved to completion. They are a selected group and their intrinsic qualities undoubtedly have contributed to the success of their treatment, whereas when children are the result of natural conception, it may or may not have been planned, which could have implications for parenting. Therefore, this should be considered when interpreting the more positive feeling couples report towards their children after ART. Finally, it would have been useful to know about the experiences of these families in the 5 years since their child was conceived. There may have been stressful events, or periods of marital discord that differentiated the groups. A more detailed retrospective examination of family histories in face to face interviews could have examined that, but the available funding did not allow that amount of face to face contact with parents. This could be explored in future research.
The results from this study should be of immense importance in understanding the implications of using ICSI, both for the child outcomes and for the impact on family life. Temperament most closely reflects any inherited aspects of childrens style of responding to the world, and the children conceived by ICSI cannot be distinguished from those conceived using standard IVF or those conceived naturally. Families are coping well and no strains were identified in marital or parentchild relationships. Therefore, clinicians can confidently assure families that there is no additional risk of negative socio-emotional impact for either parents or children.
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Acknowledgements |
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The protocol was approved by the ethics committee of each institution in accordance with national regulations in each country. The European Union 5th framework quality of life programme contract QLG4-CT-2000-00545 paid for this project entitledAn international Collaborative Study of ICSI: Child and Family Outcomes (ICSI-CFO). The funding source had no responsibility for study design or interpretation of data.
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Submitted on November 13, 2003; accepted on February 27, 2004.