Babies born via c-section are more likely to become obese¹ than those born naturally, a study has revealed.

一项研究显示，通过剖腹产出生的婴儿比顺产出生的婴儿更容易出现肥胖问题。

Research from New York University found that mice born via a c-section are more likely to have an unbalanced amount of good and bad bacteria in their stomachs, which puts them at risk for gaining too much weight.

纽约大学的研究发现，剖腹产出生的小鼠胃里的有益细菌和有害细菌数量更容易出现不平衡，从而增加它们超重的风险。

For the study, researchers observed 34 mice that were delivered by c-section and 35 mice that were born naturally.

在这项研究中，研究人员对34只剖腹产出生的小鼠和35只自然分娩出生的小鼠进行观察。

They tracked their body weights and analyzed² their intestinal³ bacteria until the mice had grown into adults.

研究人员持续追踪小鼠成年前的体重，并分析它们的肠道细菌。

The human gut⁴ has more bacteria than any other part of the body, both in number and diversity.

无论从数量还是种类上，肠道都是人体器官中拥有细菌最多的地方。

There are four major types of gut bacteria: Firmicutes, Bacteroidetes, Actinobacteria and Proteobacteria.

肠道细菌主要分为四种：厚壁菌门、拟杆菌门、放线菌门和变形菌门。

Firmicutes play a role in energy re-absorption, and may be linked to diabetes⁵ and obesity⁶.

厚壁菌门的作用是重新吸收能量，它可能与糖尿病和肥胖症相关。

Bacteroidetes account for 30 percent of all gut bacteria, and are important to our ability to digest and use energy from carbohydrates⁷ and sugars.

拟杆菌门的数量占所有肠道菌细菌的30%，对人们消化、利用碳水化合物以及糖类中的能量至关重要。

Acinobacteria produce bioactive metabolites, which we use in medicines like antibacterials.

放线菌门能产生活性代谢物，这是抗菌药等药物中含有的成分。

Proteobacteria are a category of bacteria that include diseases like chlamydia, but exist in healthy guts⁸.

变形菌门中包含沙眼衣原体等病菌，这类细菌也存在于健康的肠道内。

Mice that were born via a c-section put on about 30 percent more weight than their counterparts who'd had a natural birth.

剖腹产出生的小鼠比顺产出生的小鼠大约重30%。

Females, specifically, who had been delivered by c-section had gained a staggering 70 percent more weight than the mice born vaginally.

具体来说，剖腹产出生的雌性小鼠比其顺产出生的同类超重多达70%。

The drastic increase is credited to a difference in the bacteria found in the stomachs of the two groups of mice.

体重明显增长是因为两组小鼠肠道细菌的差异。

The microbiome, which houses such bacteria, in mice born vaginally progressed normally throughout the course of the study.

能培养此类细菌的微生物菌群在自然分娩降生的小鼠体内生长正常。

However, that of mice born by c-section, matured too quickly at first and then regressed later in their lives.

然而，剖腹产出生的小鼠起初成熟速度过快，随后发育出现倒退。

Study author Dr Maria Dominguez-Bello said: 'Our study is the first to demonstrate a causal relationship between c-section and increased body weight in mammals.'

研究报告的作者玛丽亚?多明格斯-贝罗称：“我们的研究首次证明了剖腹产和哺乳动物体重增加之间的因果关系。”

The research team said that c-sections, while critical in about 15 percent of births, are widely overused, citing that 50 percent of births in Brazil, Iran and the Dominican Republic are performed via the operation.

该研究团队表示，虽然在人类的生产中约15%的剖腹产是必要的，但很多地方都在滥用剖腹产手术，例如巴西、伊朗和多米尼加共和国的剖腹产比例为50%。

They are hopeful that their work will curb⁹ unnecessary cesareans and bring down the growing obesity rate in the US.

该团队希望他们的研究可以扼制不必要的剖腹产手术，降低美国日益严重的肥胖率。