As most of you know, I’m a bit of a research geek. I actually enjoy curling up with a good journal and cup of coffee whiling away a Saturday morning. Although I may be weird, you, my friends, are the beneficiaries of my quirkiness. It’s time now for a summary of some of the latest research on children conceived through fertility treatment, including IVF treatment. Today I’m the bearer of good news from the pages of the journal Fertility and Sterility. (I know the titles of the research sound awful and can be intimidating, but don’t let that stop you from plunging in since the results are summarized and easy to understand.)
First Study on Health Risks of In Vitro Fertilization on the Babies
“The risk of cytogenetic abnormalities in the late first trimester of pregnancies conceived through assisted reproduction”. Conway, et al. Fertility & Sterility Vol. 95, No. 2, 2011 p. 503-506
Researchers out of Cedars-Sinai and UCLA studied whether pregnancies conceived through infertility treatment were more likely than naturally conceived pregnancies to have chromosomal abnormalities. They also wanted to know if there was a difference in the number of chromosomal abnormalities depending on the type of assisted reproduction that was used—specifically comparing IVF to less invasive fertility treatments (controlled ovarian stimulation with an IUI). 559 women who conceived through fertility treatment (233 IUI, 326 IVF) were compared to 1,606 women who conceived naturally. The median ages of the women were 39 for the natural conception group and 39.4 for the infertility treatment group. All pregnancies were singletons. Chromosomal abnormalities were determined by chorionic villus sampling (CVS). This was a retrospective case-controlled study where all women with singleton pregnancies who had CVS at Cedar-Sinai Medical Center were evaluated.
No differences were found in the number or type of chromosomal abnormalities between the natural conception group and the assisted reproduction group. Also, no differences were found between the IUI and IVF group. Note , that this study focused on chromosomal abnormalities, not on birth defects in general. A large case-control study in 2009 found a higher incidence of septal heart defect, cleft lip, and esophageal or anorectal artresia among infants conceived through assisted reproduction.
Second Study on How IVF Affects the Child in Adolescence
“Pubertal development of the first cohort of young adults conceived by in vitro fertilization in the US”. Beydoun, et al. Fertility & Sterility Vol. 95, No. 2, 2011, p. 528-533
The first round of babies conceived through IVF are now reaching adulthood. I am following with great interest the research that is beginning to trickle in on these adults. Most of the research that is available on the safety of infertility treatment on the resulting children has focused on fetuses or young children for conditions that are evident early in life. This study focus on whether adolescence conceived through assisted reproduction reached puberty at roughly the same age as children conceived without fertility treatment.
The age when puberty begins is a surprisingly important factor which influences a person’s future height (shorter) and health status (risk of obesity, diabetes, cardiovascular disease, and reproductive cancers later in life). Early puberty can be caused by perinatal stress, preterm delivery, low birth weight, and fetal growth restrictions—all of which can also be associated with pregnancies from infertility treatment.
This was not a large study–173 young adults conceived through IVF between 1981 and 1990 were studied (71 male and 95 female). The average age was 21.2 years and 38% were part of a multiple pregnancy. Given the state of fertility treatment when they were conceived, no egg, sperm, or embryo manipulations, such as ICSI or assisted hatching, were done. Researchers found that conception through IVF did not affect the age of puberty onset. No cases of delayed or early puberty were found.
Image credit: bhenak (And for the record, infertility treatment does not cause adorably cute crossed eyes in newborns. )