pregnant woman looking at ultrasounds

Mom-to-be conceives a third baby — while pregnant with twins

TikTok star @TheBlondeBunny1 announced last month that she is not only expecting twins but that now she’s got a third baby on the way. How is this possible? Through an incredibly rare type of pregnancy called superfetation. (1)

TikTok Mom Conceives Third Baby Through Superfetation

When she first found out that she was pregnant with twins, TikTok superstar @TheBlondeBunny1 was over the moon. She got the surprise of her life, however, when she found out less than a week later that she had conceived a third child via a phenomenon called superfetation. (1)

The influencer, who gained fame on TikTok for being a Britney Spears look-alike, is using her platform to share her journey while she prepares to become a mom of three and educate her followers on this phenomenally rare occurrence. (1)

What Is Superfetation?

Superfetation is the creation of another fetus in a uterus that already has one. It occurs when the ova (eggs) from two separate menstrual cycles are released, fertilized, and then implanted in the uterine wall. (2)

“We knew it was two separate pregnancies,” the TikTok influencer said in one of her videos. “When you ovulate, you ovulate for 24 hours. And sperm can live in your body for up to three to five days. So our first two babies are 10 and 11 days older than our third baby.” (1)

They differ from fraternal twins because they are not fertilized at the same time – the second one can happen days or even weeks after the first. (3) It is extremely rare for a number of reasons:

1. Ovulation

In order for superfetation to occur, the woman must continue to ovulate throughout her pregnancy. This doesn’t normally happen because the female body releases hormones while pregnant to stop ovulation entirely. (3)

2. Fertilization

In order to actually develop into a fetus, the second ovum must be fertilized. This is incredibly difficult during pregnancy because usually when a woman becomes pregnant, her cervix forms a mucus plug to block sperm from getting through. Again, hormonal changes trigger this formation. (3)

3. Implantation

There are specific hormonal requirements for an ovum to become implanted in the uterine wall. Normally, those hormones are not released when a woman is already pregnant. There is also less space for a second ovum to implant itself into. (3)

For all three of these to happen together is extraordinarily rare indeed. Like anything, however, not 100% impossible.

Superfetation vs Superfecundation

Many more people have heard of superfecundation than superfetation, primarily because the former is much more common in animals, such as cats. This is when an animal becomes pregnant while they are already pregnant, however, the sperm is not from the same male. (2)

Superfecundation can happen in humans, but is of course extremely rare, whereas in cats it is actually quite common.

Are There Repercussions?

Naturally, a superfetation pregnancy automatically becomes a higher-risk pregnancy. This is because of the difference in gestational ages between the two fetuses. If the age difference is only a few days, it is not as much of a concern. If the second fetus is conceived weeks after the first, you run the risk of having a premature birth, because the woman will go into labor when the first child is ready to be born. (3)

A premature baby is at much higher risk for many complications, and the earlier they are born the longer and more severe that list becomes. (3)

Other Cases of Superfetation

TheBlondeBunny1 is not the only woman to experience a superfetation pregnancy. There are reports from 1999, 2005, 2009, 2010, and 2016 of other women experiencing the same thing. (2, 3) Some were pregnant with twins before conceiving a third time, others were pregnant with just one baby and ended up with twins. (2, 3)

In some of the cases the women were undergoing hormonal procedures to help them become pregnant, however, in several of the cases, it was all completely natural. (2, 3)

If this article has you wondering if this could potentially happen to you, the answer is technically, yes. That being said, it is so incredibly rare that it isn’t something you should spend too much time worrying about. Either way, babies are a blessing in whatever manner they are conceived.


  1. Mom-to-be conceives a third baby — while pregnant with twins.” NY Post. Marisa Dellatto. December 29, 2020.
  2. Superfetation: Twins Conceived at Different Times.” Very Well Family. Pamela Prindle Fierro. October 3, 2019.
  3. Superfetation.” HealthLine. Jacquelyn Cafasso. March 26, 2018.