According to the RCOG (Royal College of Obstetricians and Gynecologists for its acronym in English), between 1 and 2 cases of superfetation are currently registered per year.
The pharmacist Álvaro Fernández has published a video on social networks where he explains the strange conditions under which cases of superfetation can occur through his social networks.
To accompany the information he was providing, he used images and videos of one of the few recorded cases of superfetation throughout human history.
The case that the pharmacist is talking about, according to his comments, is the fourteenth registered case, where the babies that were born are twins but not twins.
Although in the photographs shared by the health professional you can see the similarity between them, the difference in size between one and the other stands out. Throughout the pharmacist’s video, he explains that superfetation occurs when a woman who is already pregnant becomes pregnant again within days of each other.
@farmaceuticofernandez superfetation #farmaceuticofernandez #pharmacy #pharmacist #health #learnwithtiktok ♬ original sound – Farmaceuticofernandez
How does the second pregnancy happen?
According to the organization of assisted reproduction, the main cause of superfetation is a new ovulation during pregnancy due to a failure in the reproductive blocking system.
When a woman becomes pregnant, high levels of the hormone progesterone cause ovarian blockage and prevent the maturation of new follicles. Therefore, an error in all this hormonal regulation of the ovary is responsible for superfetation.
In addition, it is also necessary for two other events to take place for a new pregnancy to occur:
- The penetration of sperm through the cervical mucus of the cervix, much more dense and with an antibacterial action.
- A receptive endometrium for a new embryo implantation and without affecting the already implanted embryo.
All these unusual phenomena have been associated with assisted reproduction treatments, where the woman must be administered high doses of hormones for ovarian stimulation.
Normally, the gestational difference between the two implanted embryos is 2-4 weeks. In fact, it could happen that babies resulting from superfetation have two different fathers if the woman has unprotected sex with another man a few weeks after becoming pregnant.