Parenting stress and psychosocial well-being among parents with twins conceived naturally or by reproductive technology

H. Colpin1,4, A.De Munter2, K. Nys3 and L. Vandemeulebroecke3

1 Leuven Research Centre for Parenting and Parenting Problems, 2 Centre for Methodology and 3 Centre for Family Pedagogy, Catholic University of Leuven, Department of Pedagogical Sciences, 3000 Leuven, Belgium


    Abstract
 Top
 Abstract
 Introduction
 Materials and methods
 Results
 Discussion
 References
 
This study compared parenting stress and psychosocial well-being among parents with 1 year old twins conceived in three different ways: (i) spontaneously without any medical assistance (54 families), (ii) spontaneously following hormonal treatment (25 families) and (iii) following in-vitro fertilization (IVF) or artificial insemination (AI) with the semen of the social father (24 families). The investigation included the Parenting Stress Index (PSI) and the General Health Questionnaire (GHQ-30). Since the presence of older children differed significantly between the three groups, this factor was included in the statistical analysis. Overall, no significant differences were found between the three study groups, either for the mothers or for the fathers. Nevertheless, we found a main effect of the presence of older children and an interaction effect of the presence of older children and the conception mode on some of the scales for the mothers: first-time mothers showed significantly higher stress related to parental competence, health and the partner relationship compared with mothers who had older children. First-time mothers with a history of infertility obtained significantly higher stress scores for parental competence and health and showed lower psychosocial well-being compared with naturally conceiving first-time mothers and mothers with a history of infertility who already had children.

Key words: infertility/parenting stress/reproductive technology/twins


    Introduction
 Top
 Abstract
 Introduction
 Materials and methods
 Results
 Discussion
 References
 
During the last 2 decades, thousands of children have been conceived with the assistance of reproductive technology [hormonal treatment, artificial insemination, in-vitro fertilization (IVF)]. In the case of assisted reproduction, the transition to parenthood has a particular character. Many couples must wait a long time and undergo lengthy procedures before they finally get their much-desired baby. For artificial insemination (AI) and IVF, children are conceived technically, outside the sexual relationship of their parents. Moreover, pregnancies obtained by IVF present a risk of medical complication: compared with the general population, there is an increased risk of multiple birth, miscarriage, prematurity and low birth weight (for review, see Van Balen, 1998). In Flanders (Belgium), in 1997 one-third of the pregnancies following IVF and 13% of the pregnancies obtained following hormonal treatment resulted in a multiple birth (in 95% of the cases a twin birth). At least 37% of multiple births had been conceived by reproductive technology, compared with 2% of the singleton births (Bekaert et al., 1998Go). Nevertheless, studies have revealed a desire for multiple birth among couples with infertility problems. In a study of a group of couples undergoing infertility treatment (Gleicher et al., 1995Go), 90% said they would not mind and two-thirds said they would have loved to conceive twins. The desire for triplets was lower than the desire for twins, but half of the couples indicated they would not mind having triplets. In contrast, the possibility of multiple births in excess of triplets was clearly rejected. It was found (Leiblum et al., 1990Go) that infertile women were significantly more positive about having multiple gestations than non-infertile women.

In recent years, several studies have been published comparing the parent–child relationship in families with singleton children conceived by reproductive technology and families with naturally conceived singletons (Raoul-Duval et al., 1993Go; Weaver et al., 1993Go; Colpin et al., 1995Go; Golombok et al., 1995Go, 1996Go; Van Balen, 1996Go; McMahon et al., 1997Go; Gibson et al., 1998Go). The overall conclusion is that the quality of the parent–child relationship, the children's psychosocial development and the parents' psychosocial well-being is quite similar in families with children conceived naturally without any medical intervention or following hormonal treatment, families with children conceived by IVF and families with children conceived by AI, whether or not with donor semen. In some studies, IVF and AI parents even reported a more positive relationship with their child compared with naturally conceiving parents (Golombok et al., 1995Go, 1996Go; Van Balen, 1996Go).

Families with twins conceived with the assistance of reproductive technology are in a particular position. On the one hand, the desire for a multiple birth among couples in infertility treatment may positively influence the later parent-twin relationship. On the other hand, it is possible that these couples, at this stage in the reproduction process and longing for a child, do not realize the consequences of having twins. It has been demonstrated that unrealistic prenatal expectations are a risk factor for the adjustment to parenthood (Belsky et al., 1986Go). Moreover, some of the medical and psychosocial risks associated with assisted reproduction might especially apply to multiple births. There is an increased risk of prematurity, low birth weight and perinatal mortality. Moreover, a multiple birth creates a special parenting situation, facing the parents with particular practical and emotional demands (Robin and Casati, 1994Go). These issues may be particularly stressful for (future) parents, already having passed through a long process of infertility and reproductive treatment. In one study (Gibson et al., 1997Go), IVF mothers of 1 year old twins were found to express more stress in parenting and more annoyance concerning their child's behaviour than IVF mothers of singletons.

Only a few small-scale studies have compared the parent–child relationship, the children's development and the parents' psychosocial well-being between families with twins conceived in different ways. Recently, a preliminary study of parenting quality, parental stress and child behaviour in 12 families with 4–8 year old twins conceived by IVF in comparison with 14 families with naturally conceived twins was published (Cook et al., 1998Go). No differences were found between the two groups of families in parenting quality or child behaviour. However, parents with IVF twins reported greater parenting stress compared with parents with naturally conceived twins. The latter finding may be due to `increased parental expectations amongst IVF parents and increased demands of twin parenting. An alternative explanation is that they are a reflection of greater previous parental experience among naturally conceiving parents: the majority of IVF twins in the study were first-born, whereas most naturally conceived twins had older siblings.' (p. 3245). One study (Gibson et al., 1999Go) compared 17 first-time mothers of 1 year old IVF twins with 10 first-time mothers of naturally conceived twins. IVF mothers reported more maternal stress and were perceived by others as more protective towards their twin children than non-IVF twin mothers. These findings did not translate into observed differences in the mother–child relationship. Families with pre-school twins conceived in different ways have been studied (Munro et al., 1990Go, 1992Go). The groups were matched for the age of the twins and the order in the group of siblings. IVF parents' scores on the General Health Questionnaire were similar to those of parents who conceived without any medical assistance and both groups showed significantly less well-being than the group of parents having conceived following hormonal treatment. The authors point to an apparent paradox with respect to this finding: `Patients who present at infertility clinics are informed that the use of artificial ovulants is known to increase the incidence of multiple births and also that their chances of achieving a pregnancy in that way are fairly high. Presumably, this preparedness for the increased chance of twins helps the prospective parents to become socialized into the potential role of `parents of twins' This is in contrast to the IVF couples, who have to invest a great deal of themselves and financial resources in procedures that may not lead to a desired outcome with the knowledge that the success of IVF techniques, referred to by IVF teams as the `take-home-baby rate' is still very low (Munro et al., 1990, p. 335). Concerning social relationships, IVF parents reported deficient interactions, compared with non-IVF parents. This deficiency was both in size and in affective quality of their available relationships. The authors state as a potential explanation that the parents may be reacting to the high expectations being placed on them by society in their role as `IVF parents', so they become over-involved in parenting and family and friends are largely excluded, as are leisure pursuits. Alternatively, the knowledge of IVF origins of the twinship may cause members of the social network to wish not to burden IVF parents with demands in addition to those already perceived as resulting from the IVF process (Munro et al., 1992Go).

The present study was set up in 1997. In particular, we investigated whether parenting stress and the parents' psychosocial well-being differed between three groups of families, two of whom had a history of infertility: (i) families with twins conceived by IVF or AI, (ii) families with naturally conceived children following hormonal treatment and (iii) families with naturally conceived twins without any history of infertility.


    Materials and methods
 Top
 Abstract
 Introduction
 Materials and methods
 Results
 Discussion
 References
 
Subjects
The study sample consisted of 103 families with twins. The study took place 10–13 months following the twins' birth. The mean age of the twins at the time of the study was 11.8 months (SD = 1.0). Of these families, 40 had been recruited in collaboration with the maternity hospitals in three areas in Flanders (Belgium) in an earlier stage of the study (Colpin et al., 1998Go; Nys et al., 1998Go). The gynaecologists were asked to introduce the study to women with a twin pregnancy at their consultation. In 18 of the 22 hospitals contacted, all gynaecologists agreed to participate. In four other hospitals, some or all gynaecologists refused participation. Of 50 families having participated in the first phase of the study, 40 (80%) were willing to participate again. The remaining families were recruited with the assistance of the Flemish governmental organization for mother and child care `Kind en Gezin' (`Child and Family'): among the women having delivered twins within the study period in the same areas, those not having been recruited in the first phase of the study were asked to participate. Of 77 mothers contacted, 63 (82%) were willing to collaborate.

All mothers of the 103 families agreed to participate. One of these mothers was single. Of 102 male partners, three refused to participate.

Multiple pregnancies that were naturally conceived comprised slightly more than half of the sample (54 families, 52%), 24% (25 families) were conceived following hormonal treatment and 24% (24 families) following AI (with spermatozoa of the social father) or IVF. The distribution of the method of conception was not significantly different from the national statistics (Bekaert et al., 1996Go).

The mean (±SD) maternal age was not significantly different between the three study groups (natural: 31.4 ± 3.2, hormonal: 31.5 ± 3.7, IVF/AI: 32.3 ± 2.9). The mean paternal age also did not differ (natural: 32.7 ± 6.4, hormonal: 33.6 ± 3.8, IVF/AI: 33.3 ± 3.6).

The parents' educational background and the distribution of prematurity (Table IGo) were not significantly different between the three study groups either. However, there was a significant difference between the groups for the presence of older children in the family (Fisher's exact, P = 0.006). Further analysis revealed that families with twins conceived by IVF or AI had older children significantly less often than families with naturally conceived twins (Fisher's exact test, P = 0.0028) and families with twins conceived following hormonal treatment (Fisher's exact test, P = 0.038). We found no significant difference concerning the presence of older children between families with naturally conceived twins and families with twins following hormonal treatment. The presence (or not) of older children in the family may influence the parenting of twins. Depression in the last trimester of pregnancy has been found to be more frequent among women who already had a child, compared with women for whom it was the first pregnancy (Hay and O'Brien, 1983Go). Singleton studies have shown that the transition to parenthood is different among first-time parents compared with parents already having one or more children (Condon and Esuvaranathan, 1990Go; Fish and Stifter, 1993Go). Therefore, this variable was included and controlled for in the statistical analysis (see below).


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Table I. Demographic and medical features among 103 families with twins
 
Instruments
The parent–child relationship was assessed using a Dutch version (de Brock et al., 1992Go) of the Parenting Stress Index (PSI) (Abidin, 1983Go). This questionnaire was designed to assess the degree of stress related to parenting. It is composed of two major parenting stress domains. The parent domain is composed of seven dimensions, including `depression', `attachment', `restriction of role', `sense of competence', `social isolation', `relationship with spouse' and `parent health'. The child domain consists of six dimensions: `adaptability', `acceptability', `demandingness', `mood', `distractibility/hyperactivity' and `reinforces parent'. The PSI yields individual scores for each child and parent dimension and overall scores for the child and parent domains that are obtained by calculating the means of the scores on the respective dimensions. The higher the score, the more stress reported. In the particular situation of our study (parents with twins), mothers and fathers completed the child domain twice, for each twin separately. The reported scores for the child domain are the means of the scores for each twin. Both the original PSI and its Dutch version demonstrate a good content, and show sufficient factorial, concurrent, discriminant and construct validity and internal reliability (Abidin, 1983Go; de Brock et al., 1992Go). Cronbach's {alpha} (Cronbach, 1970Go) for the PSI-dimensions ranged between 0.74 and 0.83 for the mothers (except for the dimension attachment, {alpha} = 0.60) and between 0.74 and 0.84 for the fathers (except for attachment, {alpha} = 0.68).

The parents' psychosocial well-being was evaluated using the General Health Questionnaire (GHQ-30) (Goldberg and Williams, 1988Go; Dutch version by Koeter and Ormel, 1991Go). The GHQ was developed to detect people with emotional problems, such as anxiety and depression. The instrument is composed of questions referring to unusual and unpleasant emotions and the inability to continue normal functioning. The higher the score, the lower the well-being. The original GHQ consisted of 60 items. Several shorter versions have been developed. In our study, the 30-item version was used. Validity and reliability of the GHQ-30 have been demonstrated (Goldberg and Williams, 1988Go; Koeter and Ormel, 1991Go). In our study, Cronbach's {alpha} was 0.91 for the mothers and 0.94 for the fathers.


    Results
 Top
 Abstract
 Introduction
 Materials and methods
 Results
 Discussion
 References
 
Differences between the means on the PSI (domains and dimensions) and the GHQ-30 in the three study groups were tested, separately for the mothers and the fathers, using analysis of variance (ANOVA, 3x2 design), with the conception mode and the presence of older children being the independent variables. First, a test of interaction effects of the independent variables was done. Where the interaction effects were not significant, the ANOVA were done with the two main effects (conception mode and presence of older children in the family) (Moore and McCabe, 1993Go).

For the fathers, no significant interaction effects were found. For the mothers, significant interaction effects of the conception mode and the presence of older children were found for the PSI parent scales `sense of competence' (F2,97 = 4.58, P = 0.012) and `parent health' (F2,97 = 4.34, P = 0.015) and for the GHQ-30 (F2,97 =3.63, P = 0.030). Looking at the means in the combined categories (Table IIGo), we found for the IVF/AI group and the `hormonal' group (but not for the group with naturally conceived twins) that first-time mothers showed significantly higher stress related to competence and health and lower psychosocial well-being compared with mothers who already had children.


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Table II. Adjusted mean values in the combined categories of the conception mode and the presence of older children in the family assessed by PSI sense of competence, PSI-health and GHQ-30 (n = 103)
 
We did not find any significant effects of the conception mode on the overall PSI parental and child domain, nor on the individual PSI dimensions for the mothers. The means on the GHQ-30 did not differ significantly between the three groups either. P-values of the ANOVA ranged between 0.12 and 0.97. For the fathers, as for the mothers, we did not find any significant effects of the conception mode on the overall PSI parental and child domain, the individual PSI dimensions nor the GHQ-30. P-values of the ANOVA ranged between 0.16 and 0.96.

A significant main effect of the presence of older children in the family was found for the mothers' scores on PSI parent scales `competence' (F1,97 = 4.72, P = 0.032), `parent health' (F1,97 = 5.70, P = 0.019) and `relationship with spouse' (F1,99 = 4.21, P = 0.042): compared with mothers who already had children, first-time mothers showed significantly higher stress related to competence [for the first-time mothers, mean (adjusted) = 230, for the mothers with older children mean = 197], health (respectively mean = 322 and mean = 267) and the partner relationship (respectively mean = 272 and mean = 230). For the other PSI scales and the GHQ-30, no significant differences were found between first-time mothers and mothers who had older children. For the fathers, no significant effects of the presence of older children were found.


    Discussion
 Top
 Abstract
 Introduction
 Materials and methods
 Results
 Discussion
 References
 
Our results are in line with previous findings in singleton studies, that there is no significant difference in the parent–child relationship and the parents' psychosocial well-being between families with children conceived with the assistance of reproductive technology, compared with naturally conceived children. So overall, the influence of the method of conception does not seem more significant in families with young twins than in families with singletons. As mentioned above, it is possible that potentially greater negative effects of the specific issues in the multiple birth situation for families with twins conceived by reproductive technology are counterbalanced by a more positive attitude towards having twins among the parents.

The finding (Munro et al., 1990Go) that parents of twins conceived following hormonal treatment showed significantly higher psychosocial well-being than parents of twins conceived naturally or by IVF and that IVF parents had deficient social relationships compared with the other two groups, were not confirmed in our study. Neither did we find greater parenting stress among parents with 1 year old IVF twins, compared with naturally conceived twins, unlike a study (Cook et al., 1998Go) in families with older twins. These authors stated that their findings might be due to greater parental experience among naturally conceiving parents. Of interest in this context are the significant main effects we found of the presence of older children on the PSI parent scales `sense of competence', `relationship with spouse' and `health', and the interaction effects of the conception mode and the presence of older children in the family on feelings of competence and health and on psychosocial well-being among the mothers in our study. Since they are the only significant results in many tests, they should be interpreted with caution. Moreover, only self-reporting questionnaires were used. Further investigation, also including observational measures, about the significance of parity and conception mode for the parent–child relationship and the parents' psychosocial well-being is recommended.

The significant interaction effects support the findings by Gibson et al. (1999) of greater parental stress among first-time IVF mothers of twins, compared with first-time mothers of naturally conceived twins. Our results suggest that first-time motherhood of twins is a risk factor for parenting stress and psychosocial well-being. Moreover, first-time mothers with a history of infertility (whether they made use of hormonal treatment, IVF or AI), compared with first-time mothers without a history of infertility and mothers with a history of infertility who already had older children, are particularly at risk for parenting stress and lack of well-being. Their scores on the PSI dimension `health' and on the GHQ-30 were particularly high, compared with the normal values of the instruments. With the mean score for PSI health they belong to the 8th decile of the normal table for a non-clinical sample of mothers (de Brock et al., 1992Go). The means on the GHQ-30 were considerably higher than the conventional cut-off point of 4/5 (Goldberg and Williams, 1988Go; Koeter and Ormel, 1991Go), with scores above this point indicating lack of psychological well-being.

These findings might be (partly) explained by the infertility history. By facing infertility, the woman's well-being and self-esteem might be affected. Infertile women cannot become pregnant through simple sexual intercourse with a man. This may be perceived as a personal failure. Many infertile women do not feel like real women (Nijs, 1990Go). The transition to the `generativity stage' (the production of and care for the next generation; Erikson, 1963), one of the important stages in human development, cannot be achieved. Moreover, it has been suggested that, because of the long periods of waiting and investment in the child, the parents may develop unreasonably high expectations towards the child. The risk is that the parents will expect their long awaited child to compensate for all the suffering they have gone through. They may then be disappointed when forced to face reality (for review, see Colpin, 1994). When these women do eventually have a baby (in our study twins), it would not be surprising if they were to become increasingly strained with the attempt to be a good mother and feel less well compared with mothers not faced with infertility and mothers faced with infertility who already have one or more children and who probably are more realistic and feel more self-confident in the mother role. It has been suggested (Cook et al., 1998Go) that parents of IVF twins might be in particular need of support. Our findings suggest it may be important to provide specific (pre- and postnatal) counselling and support to first-time mothers of twins, and in particular to those with a history of infertility.


    Acknowledgments
 
The authors would like to thank Saskia Timmermans for assistance with data collection. The study was funded by the Flemish governmental organization for mother and child care, `Kind en Gezin' (`Child and Family').


    Notes
 
4 To whom correspondence should be addressed at: Catholic University of Leuven, LOGO, Vesaliusstraat 2, 3000 Leuven, Belgium Back


    References
 Top
 Abstract
 Introduction
 Materials and methods
 Results
 Discussion
 References
 
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Submitted on May 24, 1999; accepted on August 27, 1999.