成语解释：
在怀孕时就为子女定下婚约。
成语出处：
《魏书·王宝兴传》：“汝等将来所生，皆我之自出，可指腹为亲。”
成语例子：
彼时九王爷因娘娘又怀身孕，曾与骆老爷～，倘生郡主，情愿与骆公子再续前姻。 ★清·李汝珍《镜花缘》第五十六回
英文翻译：
propose a marriage by pointing to the stomach -- an old practice of marriage had been engaged to each other before they were born