Single pregnancies should be the goal of fertility doctors

Delegates at the annual meeting of the European Society of Human Reproduction and Embryology have been told that more mental health problems are faced by parents of twins than of singletons, no matter how the children were conceived. Dr Leila Unkila-Kallio, from the Helsinki University Central Hospital in Finland, told the conference that the psychological health of prospective parents should be taken into account by fertility doctors when deciding how many embryos to implant in assisted reproductive technology (ART) treatments (defined as IVF (in vitro fertilisation), ICSI (intracytoplasmic sperm injection) or frozen embryo transfer).

Dr Unkila-Kallio and her team studied ART parents of 91 sets of twins and 367 singleton babies, alongside a control group of parents who conceived naturally, resulting in 20 sets of twins and 379 singleton babies. The mothers and fathers in each group were separately assessed in relation to depression, anxiety, sleeping disorders and social dysfunction at three stages: while in the second trimester of pregnancy, when the children were two months old, and when they were one year old.

The researchers found that during pregnancy, mothers in the control group had more depressive symptoms and greater anxiety than the ART mothers for both twin and singleton pregnancies. At the same stage, fathers in all groups had similar - but lower than the mothers' - levels of anxiety.

At the two months stage, and at one year after the birth, it was found that mothers of twins in both the ART group and the control group had more depressive symptoms and greater levels of anxiety. ART fathers of twins had more depressive symptoms at the two month point than fathers of singletons; these figures were comparable to the men in the control group. However, fathers of twins in the ART group reported higher levels of social dysfunction. At one year, fathers of twins in both groups tended more towards depression and anxiety, as well as reporting more sleeping difficulties than fathers of singletons.

The research also showed that any health problems with twins (such as those associated with prematurity or low birth weight) tended to have little effect on the parents of ART babies, while similar problems were found to increase levels of anxiety and sleeping difficulties among the fathers of twins in the control group. The researchers believe that this, as well as some of the other findings, might be because ART parents are better counselled about the particular risks associated with twin pregnancies from an early stage.

The researchers indicated that more support should be given to all parents, especially fathers, in ART, as it may be the case that fathers find the transition to parenthood more difficult and have generally less social support in place than mothers, even though the results showed that twin parenthood, not ART, is what seems to have a negative impact on mental health. Nevertheless, 'We believe it is important to reduce multiple pregnancies worldwide by introducing single embryo transfers', said Dr Unkila-Kallio, adding that 'our results on parental mental health of twin parents provide further evidence to support this policy'.

In other research presented at the conference, however, it was suggested that contrary to prevalent opinion, twin pregnancies following ART are 'medically, ethically and economically desirable'. Dr Norbert Gleicher, from the Centre for Human Reproduction in New York, told the conference that when the risk data on twin pregnancies was statistically re-analysed, taking into account the 'quickest, most efficient way to help patients get what they want', twin births no longer seem to be the less desirable outcome, and said that the 'clinical, ethical and economic validity' of a move towards single embryo transfer should therefore be questioned.

Commenting on Dr Gleicher's points, Professor Joep Geraedts, ESHRE Chairman, said that there were factors that were not considered in Dr Gleicher's study and that there continue to be 'significant risks to multiple pregnancies'. He added: 'we should not be generating them deliberately'.