私も諸説の一つをシェアします。
できちゃった婚がshotgun marriageと言われるのは
shotgun（ショットガン）にはbullet(銃弾）を二つ入れられるから、
ブライドと赤ちゃんの二つに打ち込むっていう。。。（失礼しました）
Akikoさんの説が多分一般的だけど、私の地元ではコレも言われてました。
A friend of mine recently had a shotgun marriage（wedding).
「最近友達ができちゃった婚しました。」
If someone is getting married because they are pregnant, in Texas we call it a "marriage of necessity." It basically means that the couple got married because they had to.
In other words, because they got pregnant.
妊娠を理由として結婚をすることはテキサスでは "marriage of necessity" と呼ばれます。
要するに「結婚しなければならなかったから結婚した」という意味です。
言い換えれば「妊娠してしまったから結婚した」ということです。
All of these mean they are getting married because the bride is having a baby.
A rush down the aisle - the aisle is the long corridor in a church that the bride and groom walk down t actually get married. A rush down the aisle means they are getting married very quickly because of the baby
Hope this helps
Jane :)
これらのフレーズはすべて、お嫁さんに赤ちゃんができたから結婚することを意味します。
a rush down the aisle
- the aisle とは、実際の結婚式のときに新郎新婦が歩く教会の長い廊下のことです。
a rush down the aisle は、赤ちゃんのために結婚をとても急いでいることを意味します。
参考になれば幸いです。
Shotgun marriage (noun)
Informal
An enforced or hurried wedding, especially because the bride is pregnant
____________________________________________________________
Shotgun wedding (noun)
Informal
A wedding that is arranged to avoid embarrassment due to premarital sex possibly leading to an unintended pregnancy
They didn't want the child to be born out of wedlock, So they got married.
1.
many people say shotgun marriage. In my country, they call it a "must marriage".
A common belief amongst many people is that if you fall pregnant, you MUST get married. This is how the term was born.
2.
Born out of wedlock means that your parents were not married when you were born.
1.
"shotgun marriage" と言う人が多いです。私の国では "must marriage" と言います。
妊娠したら結婚しなければならない（must）と多くの人が考えています。
そこから生まれました表現です。
2.
"born out of wedlock" は「両親が結婚していない時に生まれた」という意味です。
Shotgun wedding -A wedding that happens quickly due to an unplanned pregnancy.
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Example :
After finding out she was pregnant, Mary and John had a shotgun wedding.
It was a shotgun wedding, but they sure are in love.
Dan would never have married Mia if she hadn't been pregnant. Mia's father saw to it that it was a shotgun wedding.
Shotgun wedding -予定外の妊娠によって早く行われる結婚式
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例 :
After finding out she was pregnant, Mary and John had a shotgun wedding.（妊娠がわかった後、メアリーとジョンはできちゃった婚をした）
It was a shotgun wedding, but they sure are in love.（できちゃった婚ではあったけれど、彼らは確かに愛し合っている）
Dan would never have married Mia if she hadn't been pregnant. Mia's father saw to it that it was a shotgun wedding.（妊娠していなかったらダンはミアと結婚していなかっただろう。ミアの父親はできちゃった婚だとみた）
他のアンカーの方もおっしゃるように、「できちゃった婚」はshotgun marriageですが、
もしその表現を知らなければ、
They got married because she became pregnant.
「彼女が妊娠したので彼らは結婚した」
のように説明することもできます。
ご参考までに(^^♪
Some couples find themselves in this situation, and choose to get married to provide the baby with a stable home and to avoid the child becoming a bastard.
Getting married because you are pregnant is called 'a shotgun wedding'. It is an American expression because it was believed that the man might have had to be threatened (with a shotgun!) into marrying a pregnant girl.
In Australia the colloquial (slang) expression for pregnancy is "up the duff". Therefore you could say "They had a shotgun marriage because she is up the duff!"
妊娠が理由で結婚することを'a shotgun wedding'といいます。
アメリカの表現であり、男性が妊娠した女性と結婚するように（ショットガンで）脅されたからだと言われています。
妊娠はオーストラリアでは口語表現（スラング）で"up the duff"と言います。なのでこういう風にいうことができます。
"They had a shotgun marriage because she is up the duff!"
彼らは子供ができたので結婚しました！
If a couple is getting married because the woman got pregnant, this is known as a forced marriage. That is to say, the couple are only getting married because it seems they are going to have a child together, so they should stick together and raise it. It can feel a little forced because it is based solely on having a baby, not on love.
"My sister had a forced marriage. She was pregnant when she walked down the aisle and I don't think she was very much in love with her partner anymore!"
It is common in certain cultures/religions that you need to married first before you have children, so if a couple finds out that the woman has fallen pregnant they may organize a marriage before the child is born.
アメリカ合衆国 
日本 
イギリス 
南アフリカ 
カナダ 
オーストラリア 
アイルランド 
ニュージーランド 
