Wednesday February 24, 2010
Risk of Stillbirth 4 Times Higher After IVF
AARHUS, Denmark, February 22, 2010 (LifeSiteNews.com) – Women who become pregnant with a single fetus after in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) have an increased risk of a stillbirth, according to new research out today.
The study of over 20,000 singleton pregnancies, published in Europe’s leading reproductive medicine journal Human Reproduction, found a four-fold increased risk of stillbirths for women who had IVF/ICSI compared with women who conceived spontaneously or after fertility treatment that did not involve IVF or ICSI.
Dr Kirsten Wisborg a consultant in the neonatal and intensive care unit at Aarhus University Hospital (Aarhus, Denmark), and colleagues analyzed data that had been collected prospectively from unselected, pregnant women taking part in the Aarhus Birth Cohort. The study included information on women booked for delivery between August 1989 and October 2006.
Out of a total of 20,166 singleton, first-time pregnancies, 16,525 (82%) were conceived spontaneously after less than 12 months, 2,020 (10%) after more than a year of trying (classified as sub-fertile), 879 (4%) conceived after non-IVF fertility treatment and 742 (4%) conceived after IVF/ICSI. There was a total of 86 stillbirths, giving an overall risk of stillbirth of 4.3 per thousand pregnancies.
The risk of stillbirth in women who conceived after IVF/ICSI was 16.2 per thousand; in women who conceived after non-IVF fertility treatment it was 2.3 per thousand; in fertile and sub-fertile women, the risk was 3.7 per thousand and 5.4 per thousand respectively.
Dr Wisborg said: “After adjusting for maternal age, body mass index, education, smoking habits and alcohol and coffee intake during pregnancy we found a significant, four-fold increased risk of stillbirth in women who conceived after IVF/ICSI compared with fertile women. The risk of stillbirth in sub-fertile women and women who conceived after non-IVF fertility treatment was not statistically significantly different from the risk in fertile women.
“Until now, there has been speculation that the increased risk of adverse outcomes, such as stillbirths, in assisted reproduction might be due to factors related to the underlying infertility of the couples. However, we found the risk was similar between sub-fertile couples, women who had conceived after non-IVF fertility treatment and fertile couples. This may indicate that the increased risk of stillbirth is not explained by infertility and may be due to other, as yet unexplained factors, such as the technology involved in IVF/ICSI or some physiological difference in the couples that require IVF/ICSI.”