Michael Davis and his
colleagues from Adelaide University's Robinson Institute conducted a
comprehensive study to determine the risk of birth defects related to
assisted reproductive technology (ART).
The study was
published in the New England Journal of Medicine and presented in Barcelona,
Spain at the World Congress on Building Consensus in Gynecology, Infertility
Spina bifida, cleft
palate, cerebral palsy, and gastrointestinal and musculoskeletal conditions are
some of the commonly seen birth defects associated with assisted reproductive
therapies such as in vitro fertilization (IVF), ovulation induction and
intracytoplasmic sperm injection (ICSI).
Michael Davis, the
lead author and Associate Professor at the Robinson Institute stated, "While
[fertility] treatments appear quite safe, we cannot ignore that there are
significant risks that require urgent investigation with additional ongoing
studied 302,811 pregnancies that included terminations and stillbirths between
January 1986 and December 2002 resulting from spontaneous conception and 6,163
resulting from fertility treatment. The study identified birth defects before
the age of 5 years.
Comparisons were made
in the frequency of birth defects in pregnancies with fertility treatment and
pregnancies without fertility treatment.
mentioned, "The unadjusted risk of any birth defect in pregnancies
involving assisted conception was 8.3% (513 defects), compared with 5.8% for
pregnancies not involving assisted conception (17,546 defects)."
observed that ICSI had high rates of birth defects at 9.9% while in vitro
had 7.2 percent.
Davis clarified that the
risks associated with IVF
could be attributed to age or weight of the
mother while risks linked to intracytoplasmic sperm injection were
unexplainable by the available factors.
injection (ICSI) is the direct fertilization of one egg with a single sperm
injection. And in vitro
consists of creating multiple human embryos by mixing many sperms and ova in a
petri dish in in vitro
The newly created
embryo is inserted in the womb in both these forms of artificial fertility
concluded, "Infants conceived with use of intracytoplasmic sperm injection or in vitro
fertilization have twice as
high a risk of a major birth defect as naturally conceived infants."
The experts also
compared the frequency of birth defects post fresh and frozen embryo transfer.
Fresh embryo cycles were more commonly associated with birth defects as
compared to frozen embryo cycles.
Davis' team also
studied birth defects in females using clomiphene citrate for ovulation
induction. Around 37,000 women across Australia annually use this easily
available drug. According to the study findings, the use of this drug triples
the risk of birth defects.
Dr. Davis said, "It is
very commonly used as a first-line treatment for anovulatory infertility, as it
is considered to be safe, cheap and non-invasive."
According to Dr.
Davis, further researches are required as the reproductive techniques are
continuously undergoing innovations and newer inventions might reduce the risk
associated with them.
Reproductive Technologies and the Risk of Birth
Defects; Michael Davies et al; N Engl J Med 2012; 366:1803-1813