If the embryo becomes implanted in the section of the fallopian tube found within the muscle of the uterus (called an interstitial or cornual pregnancy). The rate of ectopic pregnancy following IVF is usually 1% to 2%, far lower than the 15% recurrence risk with a spontaneous pregnancy.
Fortunately, most ectopic pregnancies are readily diagnosed very early in pregnancy using blood hormone assays for beta human chorionic gonadotropin (HCG) combined with transvaginal ultrasonography. It is now uncommon for such pregnancies to go undiagnosed leading to tubal rupture, hemorrhage, or death. Most ectopic pregnancies can be treated medically using low doses of methotrexate (a type of chemotherapy that selectively destroys the pregnancy tissue), thereby avoiding surgery. This medical therapy is 80% to 95% effective.
I had an ectopic pregnancy after a Clomid cycle that was monitored by my OB. I was 8 to 9 weeks pregnant and thought I was having a miscarriage when the ectopic pregnancy was confirmed at my first RE appointment. Unfortunately, the methotrexate therapy did not work, and I had to have surgery to remove my right fallopian tube. After determining that my remaining tube was not blocked through an HSG, and with the counsel of our new RE, we opted to move on to IVF. This option would offer the greatest chance for us to become pregnant and avoid another ectopic pregnancy.
When I did become pregnant through IVF, my RE agreed to a very early ultrasound to make sure that the pregnancy was in my uterus. I appreciated that my RE understood my concerns of having another ectopic pregnancy. He treated me as an individual instead of requiring me to wait until the typical 7-week mark to perform an ultrasound.