Use of assisted reproductive technologies like IVF carry with them an increased risk of complications for mother and child, a report from the Royal College of Obstetricians and Gynaecologists (RCOG) highlights.
These risks are partially, though not wholly, attributable to the fact that multiple births are more common in IVF. In the UK, one in four IVF pregnancies result in multiple births due to the common practice of implanting two or three embryos during treatment.
Multiple pregnancy is a risk factor for premature birth but RCOG's scientific committee found that there is an additional 23 percent increase in the chances of premature birth in IVF twins. For single births, children conceived using IVF are twice as likely to be born prematurely than those conceived naturally. Singletons conceived via IVF were also more likely to be of low birth weight.
'The poor birth outcomes and complications may be a combination of treatment and underlying features of the couple such as older maternal age', said Professor Jenny Kurinczuk, director of the National Perinatal Epidemiology Unit at Oxford University. 'However, treatment strategies can be altered to improve outcomes such as the adoption of elective single embryo transfer'.
The report also reviewed data on congenital anomalies, which affect between three and five percent of infants. It found that children conceived with IVF were more likely to be affected but that the absolute risk remained low. The increased risk here was at least partly explained by underlying infertility.
Professor Kurinczuk stressed that 'the majority of the children born following IVF will have a good outcome just like any other children'.
The report goes on to note that IVF does not appear to be associated with any risks for children later in life. No influence on brain, language or behavioural development could be detected.
The paper also looks at egg donation and notes an increased risk of related early pregnancy and birth complications here, in particular pregnancy-induced hypertension (high blood pressure). The authors remark that there is a paucity of information on the long-term outcomes of egg donation.