Bioedge.org reports that in vitro fertilization (IVF) and
ICSI birth defects may be decreasing. They cite a Western Australia study of
more than 200,000 births that included nearly 2,000 IVF and ICSI babies. Researchers
found the following from fertility clinics:
From 1994–1998, nearly 11% of babies had a birth defect
diagnosed by age 6
From 1998–2002, only about 7.5% had a birth defect diagnosed
by age 6
The lead author attributes the changes to improved
laboratory practices, wiser use of meds for ovarian stimulation, and fewer
embryos transferred.
The study included some pregnancies terminated because of birth
defects. Major birth defects were listed as cleft lip, hip dysplasia, and malformations
of the heart, abdominal wall and genitals. These affected about 8% of singleton
babies conceived through IVF and ICSI, compared to about 5% of babies conceived
naturally.
What I’d like to know: Could the “improvement” be due to
pre-implantation genetic diagnosis in which embryos found to have genetic issues
are destroyed before transfer?
Bioedge has also reported that a Danish donor passed on
severe birth defects by fathering dozens of children through a clinic in
Copenhagen. It was supposed to limit to twenty-five the number of children
fathered by one door, but the donor had fathered at least forty-three kids via
sperm distributed through fourteen clinics.
At least five offspring from this donor have been found to
have a tumor-producing nerve disorder known as Neurofibromatosis type I (NF1)
or Von Recklinghausen's disease. Though the clinic was notified about four
years ago, they did nothing to prevent further use of the donor’s sperm.
Parents are considering legal action. And Danish health officials have imposed
a new twelve-pregnancy per donor rule.
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