Identical outfits, a double stroller, double the baby cooing and gurgling, completed family – two is better than one right? Not necessarily. When it comes to in vitro fertilization and the choice of transferring one or two embryos, most fertility specialists will agree that one is better than two. The goal of Assisted Reproductive Technology (ART) is to produce a single healthy infant, the best way to achieve this goal is to transfer one embryo.
When IVF was a much newer technology, transferring two or more embryos increased the chance of at least one of those embryos implanting and resulting in a successful pregnancy. Transferring two embryos can be particularly appealing to parents needing IVF to increase their chances of achieving a pregnancy. Also as a family can be achieved at one time and a couple can save further, sometimes expensive, treatments.
However, recent success rates show it isn’t necessary to improve your chances in this way – that one embryo is just as good as multiple embryos. Combine that with the fact that transferring multiple embryos can be much more risky with potential adverse health dangers for the baby and the mother. You are now less likely to find a doctor who undertakes this routinely unless for certain indications.
Multiple pregnancies have higher risks for miscarriage, preterm birth and low birth weight children. Other problems for the children can include the need for special care at birth and long term issues such as developmental delays, lung and gastrointestinal dysfunction, cerebral palsy and other health problems.
The mother carrying twins has an increased risk of having to deliver via Caesarean section, which prolongs recovery time and adds an intrinsic risk during and after delivery. Carrying twins can also increase morning sickness, weight gain and the risk of developing gestational diabetes and blood pressure problems including preeclampsia. An even more traumatising result is the increased risk of stillbirth of one or both babies. In addition, it has been found that sleep deprivation, fatigue, marital and family stress is far higher for those caring for more than one baby at a time.
Whilst it may seem appealing to some couples seeking fertility treatment, it is extremely important to be aware of the short and long term implications involved with transferring two embryos.