In May, I did a fresh embryo transfer. The embryo was a perfect 5AA and hopes were high. Some friends had got a positive as early as 3 days after a 5 day transfer (equivalent of 8 days past ovulation) so we started testing with a FRER then. And there was a line! Same the next day and the next. But it didn’t get darker.
Finally on 6 days past transfer (6dp5dt = 11 dpo) the line was gone. It had just been the trigger.
If you are doing fertility treatment, you often have an injection to trigger ovulation. This is called a trigger shot. This usually takes place 36 hours before an insemination, or egg retrieval, but you might also use a trigger shot for a home insemination or timed intercourse.
Many of these injections will make you test positive on a pregnancy test. So if you were to do the trigger shot and test a few days later, you will get two lines.
This can lead to confusion and disappointment when people test early and think they are pregnant and later discover it was just the trigger shot. To avoid this, some people choose to test out the trigger.
What does testing out the trigger involve?
To test out the trigger, you start testing early and keep testing until the trigger disappears or until it fades and then starts getting darker every day.
This way you will be able to identify a pregnancy early and avoid getting your hopes up because of a pesky lingering trigger.
Below is an example from when I tested out the trigger following an IUI. Unfortunately, after getting blank it stayed blank.
Here is an example with a more positive outcome. The trigger started disappearing and then a line came back as the person was pregnant.
Do all trigger shots create false positives on pregnancy tests?
Nope. During IVF, some people are at risk of Ovarian Hyperstimulation Syndrome (OHSS) and in these cases doctors sometimes prefer to use a different type of trigger, such as Lupron or Decapeptyl. These do not contain anything similar to HCG and will not cause a false positive. You don’t need to test these ones out.
Common pitfalls to avoid
- Don’t assume it will be the same as last cycle or the same as someone else. Each time can be a bit different. Following my second IVF retrieval I tested with Easy@home strips again and the line disappeared way quicker than after my IUI. Even though I had the same dosage and was testing with the same brand.
- Don’t switch tests midway. I made this mistake when I tested on Easy@home strips and they were negative so I switched to FRER and got positives. The FRER was simply more sensitive so the trigger continued to show there.
- Test at the same time each day. If you try to compare a test you took after waking up one day with another you took in the afternoon, it won’t give you an accurate comparison.