One of the most common things we see from those hesitant to use fertility awareness goes along these lines: "I want to trust fertility awareness, but what if I ovulate twice in one cycle? I just can't leave that up to chance!" Well we're here to let you know it's actually not true that you ovulate more than once per cycle!
This myth is generally based on the misunderstanding between the number of times you can ovulate per cycle and the number of eggs you can release during ovulation. But there are a few other possible reasons this myth is being spread around as well. Let's dig into them!
Releasing more than one egg at ovulation
Fraternal twins are babies conceived from two separate instances of sperm and egg joining. Some people assume that because two eggs were released, they must have ovulated twice. However, a singular ovulation event can result in multiple eggs being released within 24 hours of each other.
As stated above, this is generally the most common reason people believe in multiple ovulation, or ovulating multiple times per cycle. Luckily it's one we don't have to worry too much about, because fertility awareness method rules take the 24 hour window into consideration!
Having more than one hormone surge pre-ovulation
In 2003, there was a "groundbreaking" study done on 63 regularly-ovulating women in Canada. It showed 40% of them experienced more than one hormone surge pre-ovulation. However, they explicitly state that the scanning technology used in the observations was unable to confirm whether or not the women actually ovulated, just that they had multiple hormone surges.
The pre-ovulatory hormone easiest to measure at home is luteinizing hormone, and can be measured through luteinizing hormone test strips or ovulation predictor kits. We have two amazing articles talking more about these tests (one here and the other here), but it's not abnormal to get two positive surges in this hormone during a single cycle. However, a surge doesn't necessarily mean you've ovulated, just that you may ovulate.
So for this one, we'll summarize it as you are able to have multiple hormone surges leading up to ovulation, where only the final one actually results in ovulation. The earlier ovulation attempts can be important to recognize because you won't know until after the fact if you actually ovulated.
Twins measuring different sizes
This probably isn't as common as a reason behind the myth of multiple ovulation, but occasionally twins measuring at different gestational ages is seen as proof of multiple ovulation events occurring. The most likely reason for this scenario is actually either 1. babies just grow at different rates in the womb, or 2. twin-to-twin transfusion syndrome. We know that this happens in many cases of twins because it's found in both identical and fraternal twins - and identical twins would have to be conceived at the same time as they share DNA.
Also a less-likely reason this myth came about, but still a factor to consider, is superfetation. Superfetation is when a women is already pregnant, then becomes pregnant again a month or more later, so is carrying two pregnancies with different conception dates at the same time. This is also a highly debated topic in the scientific world, and if it does occur, there are only a maximum of 10 known cases where all criteria were met to qualify the pregnancy as possible superfetation pregnancies.
Ultimately, the low evidence on superfetation and the rarity of it occurring even if it does exist together make superfetation a low likelihood for the basis of the myth of multiple ovulation.
So ultimately, no you can't ovulate more than once per cycle. Did we miss a big reason you hear about ovulating multiple times in a single cycle? If so, let us know on Instagram!