据《香港医学杂志》（Hong Kong Medical Journal）报道，一名在香港出生的小女孩体内竟然“育有”双胞胎。这名女孩在香港伊丽莎白女王医院（Queen Elizabeth Hospital in Hong Kong）出生。刚刚出生才3周，就不得不经历手术来摘除她体内的双胞胎。这2个胎儿大约已被孕育8～10周,已经长出了腿、手臂、脊柱、胸腔和内脏,身体皮肤完整。其中一个胎儿重14.2g,另一个重9.3g,每个胎儿身上都有脐带。手术很成功,小女孩在8天后就出院了。最新一期的《香港医学杂志》上详细记录了这一医学奇迹。这种刚出生的婴儿体内有婴儿的情况被称作重复畸胎,世界上每50万名新生儿中才会出现一例这类情况。目前被报道出来的案例不超过200个。

产科学和妇产科医学的专家Yu Kai-man医生认为这是香港第一例重复畸胎。他说:“医生几乎不可能在产前检查出这种情况,因为胎儿体内的胚胎实在太小了。鉴于刚出生的婴儿没法自己怀孕,因此这两个受精的双胞胎胎儿属于她的父母,它们跑到了错误的地方。”

该小女孩于2010年出生,畸形背后的原因人们仍不得而知。世界卫生组织将其归类为一种肿瘤。不过医生认为这种情况与女孩母亲多次堕胎的经历有关。一名医院发言人拒绝就此案例做出评论。

下面是《医学日报》（Medical Daily）的相关报道：

A newborn girl in China came out of her mother’s womb to be found “pregnant” herself with twins. The Chinese baby born in Queen Elizabeth Hospital in Hong Kong had to undergo surgery at 3 weeks old to remove the fetuses that were believed to be at 8 to 10 weeks of gestation. Doctors claim this is the first documented case of fetus-in-fetu in the city, an extremely rare condition that occurs in one in 500,000 births, according to the latest issue of the Hong Kong Medical Journal.

The mother of the 9-pound girl was suspected to have been pregnant with triplets, but the surviving baby interred her siblings inside her body. The two fetuses each had four limbs, a spine, rib cage, intestines, and anus, but were different in weight. The twins weighed 14.2 grams and the other 9.3 grams, and each had an umbilical cord connected to a single placenta-like mass.

A view of the spine of each fetus. Hong Kong Medical Journal

Doctors emphasized the complicated nature of this rare medical condition, and err on the side of caution. “Since it is impossible for the little girl to have conceived the pregnancy on her own, the fertilization of the twin fetuses, of course, belongs to her parents, which has gone to the wrong place. It was almost impossible to detect during the prenatal check-up, as the embryo inside the baby was too small,” said Dr. Yu Kai-man, a specialist in obstetrics and gynecology, the South China Morning Post reported.

Rare, but a possibility, there has only been 200 cases of the fetus-in-fetu phenomenon reported. When babies are born this way, they can be seen in many different ways. In the case of the newborn girl, she had a mass of fetal tissue between her liver and left kidney inside her body cavity. Doctors were able to tell there were two separate fetuses, because upon removal there were two separate partially formed fetal structures.

Fetuses-in-fetu with umbilical cords. Hong Kong Medical Journal

Aside from the possibility of being pregnant with triplets, researchers hypothesize the condition was triggered by either the mom having more than one previous abortion, or that the mass is a teratoma —— a non-cancerous tumor containing tissue, hair, and even teeth. Although the cause is still being investigated, the girl was able to make a good recovery and was discharged from the Yau Ma Tei hospital eight days after surgery.

A similar 2012 case published in BMJ Case Reports, a Chinese schoolgirl, believed to have fetus-in-fetu, grew a third arm out of her back, along with the remnants of a parasitic twin while she was still in the womb. The arm had been part of an identical twin that had failed to have been pushed out of its sister’s body. The twin also had a breast and an arm with a shoulder blade and two fingers.

Chinese school girl grew a breast, and an arm which included a shoulder blade and two fingers, believed to caused by fetus-in-fetu. BMJ Case Reports

These cases may be prevented with early testing and early detection. "The widespread use of antenatal ultrasound in early gestation may provide more concrete evidence … and shed light on this intriguing condition," the researchers wrote.