IVF Method May Be Safer Than Ever

In vitro fertilization tied to fewer premature births and higher birth weights compared to 20 years ago

(RxWiki News) Parents-to-be want their babies to be born as healthy and happy as possible. One pregnancy method is getting safer, which could enable more parents to make sure that happens.

A new study of birth outcomes of children born after in vitro fertilization (IVF) treatments found a significant decline in the number of non-twin babies born prematurely or with a low birth weight over 20 years. Also, rates of stillbirths among both twins and single babies declined during that time.

The authors of this study suggested that outcomes for IVF babies may be improving due to lower rates of twin births.

“Transferring several embryos in one cycle, even if it results in only a single baby, can still have a negative impact on the overall neonatal outcomes of singletons,” said lead study author A. A. Henningsen, MD, of Rigshospitalet at the University of Copenhagen, in a press release.

IVF involves the fertilization of an egg by sperm in a lab. The egg is then implanted into a woman’s uterus in hopes of a successful, healthy pregnancy. Sometimes, doctors fertilize and implant several eggs at the same time to increase the chance of pregnancy. This often results in a pregnancy with twins, triplets or even more “multiples.”

This study looked at data from all IVF single babies and twins born in four countries over 20 years — more than 62,000 single babies and nearly 30,000 twins.

Dr. Henningsen and team looked at whether the babies were premature, whether they had low birth weights and other unwanted birth outcomes. They compared the data to a control group of more than 360,000 babies conceived without IVF.

These researchers found that, over time, the single IVF babies became less likely to be premature or have low birth weights.

Also, rates of stillbirths gradually declined among both single babies and twins conceived using IVF. IVF twins had even lower stillbirth rates than twins conceived without IVF.

Dr. Henningsen and colleagues attributed these more positive birth outcomes to growing rates of single-embryo IVF implantations.

“By transferring only a single embryo, you not only avoid multiple births and all the health problems for the babies and mothers associated with these, but it also results in healthier [IVF] singletons because there are fewer instances of 'vanishing twins' or procedures to reduce the number fetuses developing after successful implantation of several in the mother's womb,” Dr. Henningsen said.

These researchers said IVF has become much safer for babies over the past 20 years.

This study was published Jan. 20 in the journal Human Reproduction.

The European Society of Human Reproduction and Embryology, the University of Copenhagen and the Danish Agency for Science, Technology and Innovation funded this research. Dr. Henningsen and team disclosed no conflicts of interest.

Review Date: 
January 20, 2015