Scientists are also working to develop chemicals to control the birth rate in deer populations.(科學家們也在努力研制化學物質來控制鹿群的出生率。)

Birth rate and the stork population are connected.(出生率與鸛的數量有關。)

As Indonesia prospers, its birth rate is falling; South Asia's remains very high.(隨著印度尼西亞走向繁榮，該國的出生率正在下降，而南亞的出生率則依舊保持在很高的水平上。)

A: In Europe, what people really care about is not the marriage rate but the birth rate.(回答：在歐洲，人們真正關心的不是結婚率而是出生率。)

The birth rate in Europe is rising slightly(歐洲人口出生率略有上升)

The CDC study did not explore why the teen birth rate is at an all-time low.(疾病控制中心的研究并沒有探究出為什么青少年出生率總是處于低比率狀態。)

Germany's population is ageing, and the birth rate falling.(德國的人口老化，出生率下降。)

The birth rate among professional women is particularly low.(職業女性的生育率則更低。)

Several factors have been adduced to explain the fall in the birth rate.(有幾個因素已被援引來說明出生率降低的原因。)

The out-of-wedlock birth rate among women who drop out of high school is 15%.(高中輟學的婦女中非婚生子女出生率為15%。)