Male Pregnancy: A Dangerous Proposition

Is it possible for male humans to carry babies? Many scientists hope not
A few intrepid researchers are learning how to make babies the new-fashioned way: growing them in artificial wombs Holly Lindem

All signs point to pregnancy: increased appetite, a bulging belly and an ultrasound that shows a growing fetus. But the patient, Lee Mingwei, is a man.
He is also a performance artist, and the images of his swollen abdomen and kicking baby are part of his hoax Web site But is it only a matter of time before the idea of a baby-bearing dad moves beyond the realm of hoax and into the delivery room?

Robert Winston, a pioneer of in-vitro fertilization, created a stir in 1999 when he told London’s Sunday Times that “male pregnancy would certainly be possible.” In rare cases, women have given birth to babies that developed outside the uterus–a phenomenon known as ectopic or extrauterine pregnancy. Winston argued that men should also be able to bear fetuses in their abdominal cavities. But male pregnancy would be complicated and, scientists say, potentially fatal.

A doctor would first administer a battery of hormones, including estrogen and progesterone, to prepare the male body to support a developing fetus. Side effects of the hormones could include the development of breasts, sterility, even cancer. A surgeon would then implant an embryo, created by in-vitro fertilization, in the wall of the man’s peritoneum, the membrane that lines the abdominal cavity. If all went well, the fetus would grow inside the abdomen until delivery by cesarean section.

The delivery would probably be the most dangerous part of this hypothetical process, because there would be a high risk of hemorrhaging. During pregnancy, the placenta extends villi, hairlike projections containing blood vessels, into the surrounding tissues to establish a blood supply for the baby. Unlike the uterus, the abdomen is not designed to separate from the placenta during delivery. The placenta would become so bonded to the man’s body that it might be impossible to surgically remove it without also removing parts of abdominal organs, such as the bowels. The likely end product: a gaping wound in the abdomen and heavy, uncontrolled bleeding, says Gillian Lockwood, medical director of Midland Fertility Services, a leading British fertility clinic.

The alternative–leaving the placenta in place–could be even more dangerous. The placenta would shrink after the birth, thus possibly rupturing the blood vessels attached to it. There would also be a high risk of infection caused by the dead placental tissue. “The question is not ‘Can a man do it?’ ” says bioethicist Glenn McGee of Albany Medical College. “It’s ‘If a man does have a successful pregnancy, can he survive it?’ “

The pregnancy would pose serious health risks to the baby as well, according to Lockwood. Without a womb to protect it, the fetus would be in an unusual position and under unusual pressures, which could cause malformation of the limbs or organs. There would also be a high risk of premature birth, either as a result of abdominal pain or a rip in the amnion, the membrane surrounding the fetus.

McGee estimates that male pregnancy is 20 years away, but others believe Lee Mingwei’s prank is as close as we’ll ever get. “Saying it’s possible is very different from saying anyone would ever advocate it,” Lockwood says.

Efforts to develop artificial wombs, using female uterine cells grown on biodegradable structures, could open a new avenue to male pregnancy. But for now, implantable artificial wombs are not far enough along to know what the side effects might be, says Simon Fishel, managing director of CARE Fertility Group, another top British clinic.

Even if men won’t be suffering from morning sickness and pickle cravings anytime soon, it doesn’t mean there aren’t any knocked-up dads in the animal kingdom. Male seahorses and pipefish, a closely related species, carry the brood in the family. The female of these species deposits her eggs in the male’s pouch, where they are fertilized and stored until he goes into labor a few weeks later. For that rare man who longs to be pregnant, perhaps Mother Nature isn’t entirely opposed to the idea after all.