UNDERSTANDING INFERTILITY
are fertilized either by co-culture with sperm or
direct intracytoplasmic sperm injection (ICSI),
and the resulting embryos are most commonly
cultured to the blastocyst stage of development,
where they can either be transferred back to the
uterus or cryopreserved for future use. Embryo
selection is traditionally based on morphometric
grading, though many patients now elect to use
preimplantation genetic testing (PGT) to screen
for aneuploidy, monogenetic disorders and other
genetic factors that may affect the prognosis of an
embryo and resulting child.
Modern IVF treatment should be distinguished
from its earlier iterations on several points, but first
has to be its safety. One of the main risks associ-
ated with IVF treatment is multiple gestation: the
incidence of which is directly correlated with the
number of embryos that are transferred at a time.
However, with the combined benefits of contem-
porary lab technologies and genetic screening of
embryos, most practices now prioritize the use of
elective single embryo transfer (eSET). In 2017,
43.9% of all transfers in the country were eSET
Dr. Hunter with Louise Brown, the world’s first baby born from IVF treatment.
cycles. At Kentucky Fertility Institute, our average
number of embryos transferred per cycle across all
and prospectively adjust treatment protocols to essentially obviate
age strata for the year was 1.2, and our cumulative rate of multi-
the risk moving forward. By utilizing tools such as GnRH agonist
ple pregnancy was 11.1%, all of which were twin gestations. Our
triggers, freeze-all protocols and medications designed to abate the
twinning rate in women under 35 was only 6.9%, which compares
hormonal drivers of OHSS, we have nearly eradicated the syndrome
quite favorably to published rates for alternate infertility treatment
from modern practice, with severe presentations now being effec-
options such as ovulation induction (8 to10%) and superovulation
tively reduced to case reports.
therapy (20 to 30%). In fact, we’ve seen a number of women at our
As the safety profile of IVF has improved, we have also seen a
practice who specifically elect to pursue IVF treatment because of
notable expansion in the spectrum of its clinical utility over recent
its advantageous rate of multiples - with planned eSET therapy, rates
years. While initially developed as a treatment for tubal-factor in-
of twinning should be no higher than 1 to 2% (all monozygotic,
fertility, IVF is now commonly used to treat male-factor infertility,
by definition).
unexplained infertility, advanced-stage endometriosis, diminished
The other risk commonly associated with IVF is ovarian hy-
ovarian reserve, women of advanced reproductive age, hypothalamic
perstimulation syndrome (OHSS), which is characterized by hor-
amenorrhea, drug-resistant polycystic ovarian syndrome, recurrent
mone-driven ascites formation and resulting metabolic sequelae.
pregnancy loss, couples at risk for having a child with a genetic dis-
Mild cases associated with nausea and pelvic discomfort were
order, couples with prior sterilization procedures, same-sex couples
previously reported in up to 6% of women undergoing IVF treat-
pursing reciprocal IVF (one partner supplies eggs; the other carries
ment. More severe features were reported in 1 to 2% of patients, and
the pregnancy), patients utilizing an oocyte donor and/or gesta-
complications related to excessive ascites formation (e.g., pleural
tional carrier, and patients desiring fertility preservation for future
effusion) and resultant hemoconcentration (e.g., thromboembolic
pregnancies to name a few. Currently, tubal disease is the indication
events) were occasionally seen. Fortunately, improved understand-
for IVF treatment in only about 12% of cycles nationwide, which
ing of the pathophysiology of this condition has given modern
demonstrates the breadth of its modern utilization in our field. Fu-
providers the reliable ability to recognize patients at risk for OHSS
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