Briefly, the authors found that, for certain kinds of infertility,
artificially inducing a woman to ovulate and artificially inseminating her by
depositing her partner's sperm directly into the uterus resulted in more
pregnancies than did several similar techniques.
"The demand for effective infertility treatments is high and this
frequently leads to use of therapies that haven't been tested by clinical
trials," said NICHD Director Duane Alexander. "This rigorous
evaluation--perhaps the most comprehensive of its kind--will provide invaluable
information for those who need it most."
The research team was composed of scientists in NICHD's National
Cooperative Reproductive Medicine Network, and the study's first author was
David S. Guzick, MD, PhD,of the University of Rochester, in Rochester, New York.
In all, the investigators tested 932 couples with infertility in which
the woman appeared to ovulate normally, including what is known as unexplained
infertility as well as less severe forms of male factor infertility. Couples
who have this condition are unable to conceive a child, despite the fact that
the woman appears normal and her male partner produces at least some sperm,
explained Dr. Donna Vogel, Associate Chief for Clinical Research of NICHD's
Reproductive Sciences Branch and a coauthor of the study.
The couples who took part in the study were assigned to one of four
groups. In the control group, the women did not receive any drugs to induce
ovulation, and were inseminated in the cervix (intracervical insemination).
Insemination took place when the women's urinary levels of luteinizing hormone
(LH) peaked. A surge in (LH) indicates that ovulation is taking place.
In the second group, the women did not receive any drugs to induce
ovulation but were inseminated in the uterus with their partner's sperm
(intrauterine insemination) when their urinary levels of luteinizing hormone
The third group of women received injections of follicle stimulating
hormone (FSH) to induce them to ovulate, and then received intracervical
insemination. The fourth group received FSH injections and intrauterine
The 231 women in the group receiving FSH injections and intrauterine
insemination had the highest rate of pregnancy, at 33 percent. In comparison,
the 234 couples receiving induced ovulation and intracervical insemination had a
pregnancy rate of 19 percent, the 234 women receiving intrauterine insemination
timed to coincide with a surge in LH had a pregnancy rate of 18 percent, and the
233 women receiving intracervical insemination timed to a surge in LH had a
pregnancy rate of 10 percent.
"Clearly, treatment with induced ovulation and intrauterine insemination
is more effective in this population than any of the other methods we tested,"
Dr. Vogel said. "This information is particularly important in view of the high
costs of the procedures involved -- induced ovulation, for example averages about
$1,300 per cycle."
Dr. Vogel noted, however, that these procedures are considerably less
expensive than many other infertility treatments.
Dr. Vogel added that pregnancy rates in each of the four groups were not
affected by the women's age or the man's age. However, pregnancy rates declined
with longer durations of infertility: the pregnancy rate was 28 percent, for
couples who had previously experienced 12 to 23 months of infertility; 20
percent with 24 to 35 months of infertility; and 17 percent, with 36 months of
Dr. Vogel cautioned that any couple considering the infertility
treatments mentioned above should be advised of the risks involved. From one to
two percent of women receiving superovulation -- the treatment used to induce
ovulation -- may require hospitalization for ovarian hyperstimulation. This
condition may result in extreme swelling of the ovaries, accumulation of fluid
in the abdomen and lungs, as well low blood pressure and a high pulse rate.
Superovulation may also lead to the release of large numbers of eggs, which
could lead to a multiple pregnancy. In this study, the researchers took
precautions against a large number of conceptions. For example, they did not
inseminate the women when the ovaries appeared to contain a large number of
eggs. In all, 6 of the women undergoing superovulation were hospitalized due to
ovarian hyperstimulation, 3 of whom were pregnant. Other researchers are
looking at whether or not superovulation may increase the risk of ovarian
Of the pregnancies that resulted in the study, there were three
quadruplet pregnancies, one in the superovulation and intracervical insemination
group, and two in the superovulation and intrauterine insemination group.
Similarly, there was one triplet pregnancy in the superovulation/ intracervical
insemination group, and three triplet pregnancies in the
superovulation/intrauterine insemination group. Of the 18 sets of twins, 17
were in the superovulation groups.
"We conclude that for infertile couples in which the woman has no
identifiable infertility factor and the man has motile sperm, the combination of
superovulation and intrauterine insemination is an effective means of achieving
pregnancy," the study's authors wrote.
The authors concluded that physicians devising treatment for their
infertile patients should consider the costs of the various procedures, the
women's age, the results of semen analysis and weigh them against the incidence
of ovarian hyperstimulation and the likelihood of multiple pregnancy.
"We recommend that couples be informed of all their options, be given
realistic information about the chances of success as well as the costs and
complications, and be involved in the final decisions," they wrote.