Assisted Reproductive Technology and Pregnancy Outcome
Abstract & Commentary
By John C. Hobbins, MD, Professor and Chief of Obstetrics, University of Colorado Health Sciences Center, Denver, is Associate Editor for OB/GYN Clinical Alert.
Dr. Hobbins reports no financial relationship to this field of study.
In November the authors of the now famous FASTER trial, which was initially focused on the use of nuchal translucency (NT) in the first trimester, published one of many spin-off reports. This one dealt with outcomes of singleton pregnancies conceived through assisted reproductive technology (ART). In this large study 1,222 pregnancies were accomplished through ovulation induction and 554 were conceived by in vitro fertilization (IVF). The remaining 34,286 spontaneously occurring pregnancies were used as controls.
The abstract of the paper says it all. When compared with no ART, ovulation induction carried a significantly greater risk of placental abruption (OR, 2.4), fetal loss after 24 weeks (OR, 2.1), and gestational diabetes (OR, 1.5). IVF was associated with a higher risk of preeclampsia (OR, 2.7), gestational hypertension (OR, 1.6), placenta previa (OR, 6.0), placenta abruption (OR, 2.4), and risk of Cesarean section (OR, 2.3).
The above results that were easiest to explain were IVF’s predisposition towards placenta previa, preeclampsia, and abruption, which could be secondary to an inability for the placenta to find a receptive decidual bed. This would also explain the rather high rate of vasa previa with IVF as noted in a previous Clinical Alert. The higher rate of Cesarean section after IVF is not surprising in IVF patients in whom the reasons for Cesarean sections might be more socially related rather than medically indicated. The higher rate of gestational diabetes in those with ovulation induction (and not with IVF) could well be due to a higher proportion of patients with polycystic ovarian syndrome (PCOS) in the former group.
Although the study did not show a significant relationship between ART and low birth weight (LBW) an analysis by the CDC involving data from 1996-1997 showed almost a doubling of the LBW and a similar review from Sweden showed a 6-fold increase in LBW with IVF pregnancies.
The point is that not all is rosy for the often desperate and vulnerable patients conceiving through ART. It is my impression that these patients often turn a deaf ear (if they are properly informed) to the downside of carrying twins or triplets. In fact, recent data suggest that the perinatal mortality and morbidity is higher in multiple gestations conceived through ART then those occurring spontaneously. Now, the data from the above FASTER trial and from other studies show similar trends with singletons.
One hopes that this information will find its way into ART consent forms in large print.
- Centers for Disease Control and Prevention, American Society of Reproductive Medicine, Society for Assisted Reproductive Technology, RESOLVE. 2001 assisted reproductive technology success rates: national summary and fertility clinic reports. Atlanta (GA): Centers for Disease Control and Prevention; 2003.
- Jackson RA, et al. Perinatal outcomes in singletons following in vitro fertilization: a meta-analysis. Obstet Gynecol. 2004;103:551-563.
- Bergh T, et al. Deliveries and children born after in-vitro fertilisation in Sweden. 1982-95: a retrospective cohort study. Lancet. 1999; 354: 1579-85.
- Schieve LA, et al. Low and very low birth weight infants conceived with use of assisted reproductive technology. N Engl J Med. 2002;346:731-737.