Low Risks of ART Reported at ASRM Meeting
More than five million children have come into the world thanks to assisted reproductive technology (ART).1
The picture is still somewhat incompletelargely because its difficult to tell whether other social, environmental, or medical factors such as multiple births are influencing outcomes. However, studies presented at the recent 2014 Annual Meeting of the American Society for Reproductive Medicine (ASRM) provided mostly reassuring findingsfor both children and mothers.
Low overall birth defects. Between 2004 and 2008, researchers examined more than 300,000 births in Massachusettsincluding 11,000 children (3.8 percent) conceived with the help of reproductive technology. These ART-conceived children had slightly higher rates of cardiac and non-cardiac birth defects than children, but their overall rates of birth defects were low.2
Common childhood cancers not increased. A second study offered a preliminary analysis of 113,892 children conceived by ART. Conducted by investigators at the University of Minnesota, this study found that these children were not at increased risk for common childhood cancers, such as leukemia and embryonal tumors.3 The findings differ from two previous reports, which showed an increased relative risk for cancer associated with ART.
The population-based study linked state cancer registries with live birth records from 2004 to 2009 in the Society for Assisted Reproduction Clinic Outcome Reporting System. Although the study involves 16 states, not all have submitted complete data. The researchers say a larger sample size and further studies are needed to draw any firm conclusions about other types of cancer, especially given that both ART and childhood cancers are rare events.
Low cancer risks after ovarian stimulation. For decades, questions have persisted about potential risks to women whove undergone ovarian stimulation before vitro fertilization (IVF). Researchers from the Netherlands Cancer Institute and Erasmus University Medical Center in Rotterdam helped put some of those worries to rest at ASRM with reports on two nationwide cohort studies.4
Identifying cancer cases through the Netherlands Cancer Registry, the researchers compared more than 19,000 women who had received IVF an average of 17 years prior with nearly 6,000 who had not had the procedure.
Women who had had ovarian stimulation prior to IVFregardless of drug dosages or numbers of IVF cycleswere not at increased risk of developing colorectal cancer. Likewise, risks for uterine (endometrial) cancer werent increased, no matter the number of cycles or causes of the womens infertility. Those who did not have children, however, were at slightly greater risk of developing cancer.
Double trouble? Although these previous studies point to overall low risks attributable to ART, the same cant be said for twin births following ART, according to a large study conducted in Massachusetts.5
With the help of public health records, researchers compared birth outcomes between 2004 and 2008 for 6,000 singleton pregnancies and 2,500 twin pregnancies. Controlling for other factors such as parental age and infertility diagnoses, they tracked risks for:
- Preterm birth
- Low birth weight
- Small size for gestation
- Pregnancy hypertension
- Gestational diabetes
- Prenatal admissions
- Primary cesarean delivery
Risks for triplets and high order multiple pregnancies have long been known, and these types of pregnancies have begun to decline in the United States.6 But this study confirmed that even twin births, which have not declined,6 put both mother and child at much greater riskmaking an even stronger case for the use of elective single embryo transfer (eSET). As we discussed in the last issue of Fertility Flash Newsletter, PFC has been a national leader in technologies enabling this approach for many years and we stand firmly by our motto, One healthy baby at a time.
Other ways to reduce risks. Aside from reducing the number of embryos implanted, there are other ways women can enhance the chances of a healthy pregnancywhether or not they are undergoing ART.7
You may be well aware of most of these guidelines, but they certainly are well worth repeating. Women should:
- Take 400 micrograms of folic acid every day. Do this at least one month before you become pregnant and throughout your pregnancy. This important B vitamin helps prevent major brain and spine birth defects in babies.
- Avoid alcohol and cigarettes. We dont know if there is a safe amount to drink during pregnancy. That means its wise to avoid all alcoholincluding wine and beerduring your entire pregnancy. The same goes for cigarettes.
- Prevent infections. Some infections are harmful to an unborn baby. Take extra care to wash your hands and cook meat until its well done. Also, dont touch or change cat litter, and avoid people with infections.
- Get clear about meds and shots. Your doctor can advise you about which shots are safe and helpful during pregnancy. Also discuss whether you should avoid any prescription or over-the-counter medications, but dont stop taking them without first having a talk with your doctor.
- Manage your weight. Reaching and staying at a healthy weight can help you reduce complications during pregnancy. Along with other steps, it can also help you manage diabetes.
- Team up. Perhaps most important of all? Stay in touch with your health care team before, during, and after your whole pregnancy.
- Minerva Ginecol. 2014. Oct;66(5):431441. Long-term outcomes in children conceived with assisted reproductive technologies.
- ASRM news release: ART is Not a Major Risk Factor for Birth Defects. 10-21-14.
- Medscape: No Increased Cancer Risk in Assisted-Fertility Offspring.
ASRM 2014 Annual Meeting: Abstract 0148.
- ASRM news release: Ovarian Stimulation for IVF Does Not Increase Risk of Endometrial or Colorectal Cancer: Results from a Nationwide Cohort Study. 10-21-14.
- ASRM news release: Even Twin Births Following ART Increase Risk for Child and Mom. 10-20-14
- CDC: Assisted Reproductive Technology SurveillanceUnited States, 2011. 11-21-14.
- CDC: Guidance for Preventing Birth Defect.
- The PFC Team