Safe sex is vital for young couples who don’t want to have children, but some methods may not be as pregnancy-proof as you might think.
In fact, women have conceived children in surprising ways that seem to defy the laws of biology.
One factor that unites them all is the resilience of the human reproductive system and its ability to function in the face of adversity.
Professor Adam Taylor, from Lancaster University, has detailed how women can become pregnant in four extremely rare circumstances: anal sex, oral sex, a “shock” insemination without any penetration and while they are already pregnant.
Getting pregnant through anal sex is extremely rare, but it can happen in people with a reproductive abnormality called cloacal malformation.
Anal sex may seem like a safe option for couples trying to avoid pregnancy, but a rare condition can allow sperm to reach the egg.
The only truly safe way to avoid pregnancy is to use contraception, experts say
This occurs when the division between the tissue that divides the vagina and the anus does not form correctly.
When this happens, it can allow sperm to swim through any opening in the dividing wall toward the egg to fertilize it.
Professor Taylor said sperm are naturally drawn to an egg by “smelling” out small amounts of chemicals it produces, and will take any route necessary to reach their target.
“They are able to detect traces of chemicals produced by the egg,” he said. The conversation.
‘As sperm swim toward the egg, the amount of these “chemoattractants” they detect increases, signaling them to continue traveling in the right direction.’
Cloacal malformation affects one in every 50,000 girls and requires corrective surgery.
There is a high probability of complications with this surgery such as incontinence and difficulty getting pregnant.
Medical records contain details of a pregnancy caused by a strange set of circumstances that began with oral sex in 1988.
A 15-year-old girl living in the southern African nation of Lesotho went to her doctor with abdominal pain and discovered she was heavily pregnant.
Oral sex should be a safe bet to avoid pregnancy, but the determination of sperm to achieve its goal should not be underestimated.
A girl born without a vagina ended up pregnant in 1988 after a traumatic experience that began with oral sex (file photo)
But incredibly, the girl had been born without a vagina, a condition called Mullerian agenesis, leading everyone to wonder how this had happened.
It emerged that nine months earlier, she had been performing fellatio on her lover and was caught in the act by her jealous ex-boyfriend, who immediately stabbed her in the stomach.
She went to the hospital and was treated, but not before her lover’s stray sperm found its way into her system.
Sperm are known to be able to survive in the peritoneal cavity, the space between the abdominal organs and the body wall.
In the girl’s case, her lover’s brave swimmers managed to reach her egg and fertilize it, possibly through her gastrointestinal tract.
Doctors delivered a healthy baby by Caesarean section, according to a report in the British Journal of Obstetrics and Gynaecology.
There are other ways that women can get pregnant, even if they haven’t had sex.
“If semen splashes onto the external genitalia, sperm can reach the vagina and swim to the ovaries,” Professor Taylor explained.
Women can get pregnant during sexual activity, even if they have not had full intercourse.
Healthy sperm have great resistance and can survive half an hour outside the human body.
So-called “unplanned pregnancies” are very unlikely because sperm cannot survive more than half an hour outside the body.
Healthy sperm swim at a speed of up to 5 mm per minute and can survive up to five days in a woman’s genitals.
During sexual intercourse, under ideal conditions, hundreds of millions of sperm are released into the vagina, but only 200 to 300 reach the egg, proving that accidental pregnancies are so rare.
They cannot be produced from sperm present in bath water or hot tubs, because water disperses sperm and dilutes the seminal fluid that protects them.
Chemicals like chlorine in water also quickly kill sperm.
In very rare cases, it may be possible for a woman to become pregnant a second time while already pregnant.
This phenomenon, called superfetation, negates all the “safety measures” that normally prevent a second pregnancy.
Hormonal changes during pregnancy usually prevent a second pregnancy from occurring.
In very rare cases, called superfetation, a second egg can be fertilized while a woman is already pregnant.
During pregnancy, a woman’s hormones change to prevent an embryo from implanting in the lining of the uterus.
Even if a second embryo were somehow formed, it is unlikely that it could begin to grow in the uterus.
This is true even for women born with two uteruses, as these mechanisms work hard to prevent a second pregnancy from occurring.
Hormones prevent ovulation and produce a thick mucus plug that covers the cervix to prevent sperm from traveling from the uterus to the ovary.
But very occasionally, usually in women undergoing IVF treatment, these safety measures may be ignored.
The two pregnancies usually occur very close to each other, usually two to four weeks apart.
While the babies will not be twins, it does mean that they can usually be born together at the same time.
Most of these pregnancies progress normally without complications.
Professor Taylor said: “These cases are of course extremely rare, so you probably don’t need to worry too much. But if you don’t want to get pregnant in the near future, make sure you use contraception.”