fertility rate

High fertility rate is a big problem but one of the biggest problems is the early onset of the first pregnancy , and maternal death and child death is greatly enhanced if the mother is young .

高人口出生率是一个大问题，但是最大的问题之一是首次怀孕过早，如果母亲太年轻，母婴死亡率将极大地增加。

By comparison , the fertility rate in developed countries has been stable , or falling .

比较而言，发达国家的人口出生率已稳定下来，或者说在下降。

Optimal Fertility Rate Control for Age - Dependent Population System

年龄相关的种群系统的最优生育率控制

Some results on the critical value of variable specific fertility rate with time

关于时变总和生育率β（t）的临界值的几个结果

Population Control Under Low Fertility Rate in China

低生育率条件下的中国人口控制

A Composite Age - Specific Fertility Rate Model Based on Random Distribution Functions

基于随机分布函数的分年龄别生育率组合模型

The fertility rate of this group is 67 % .

怀孕率占67%。

The Changes of Social Mobility Mechanism 's Effects on Fertility Rate in Rural

社会流动机制的转变对农村生育率的影响

Identification of the Total Fertility Rate for the Distributed Parameter Control System of Population

一类人口分布参数系统的总和生育率的同定问题

The scholars used to study the fertility rate from the aspect of culture .

在过去的生育率研究中，学术界习惯于从文化学的角度进行分析。

City Problems Caused by Low Fertility Rate

低生育率带来的城市问题

Estimation and Analysis on Total Fertility Rate

总和生育率的测算及分析

Critical Fertility Rate of Women in Population Problem

人口问题中的妇女临界生育率

Remark on the Necessary Conditions of Optimal Fertility Rate Control for Time-varying Population System

关于时变种群系统最优生育率控制存在性的必要条件的注记

Census officials said the current fertility rate was 1.7 .

人口普查官员表示，目前的生育率为1.7。

Probability Model of Women 's Fertility Rate

妇女生育模式概率模型的探讨

Women 's Status and Total Fertility Rate

女性社会地位与总和生育率

The Social and Economic Variables Affecting the Fertility Rate in China : An Observation of 1990-2000

中国各地区妇女生育水平差异的社会经济影响因素分析兼对19902000年期间各地区生育水平下降因素考察

To control population quantity , we need reduce the fertility rate and realize bearing transition .

控制人口数量，需要降低生育率，实现生育转变。

Experimental results also showed a positive correlation between percentage of functional pollen and fertility rate .

正常花粉率与稔实率相关极显著。

Since our country fertility rate change always all has close relationship with the birth civilization development .

摘要我国的生育率变化一直以来都与生育文明的发展有着密切的关系。

Stabilizing low fertility rate will bring very important influences to the elder security .

稳定低生育水平会对养老保障产生重大影响。

Marital fertility rate may bethe future trend of change ?

婚内生育率未来变化的可能趋势如何？

The Influence Factor on Fertility Rate of Tujia Nationality Women in Hubei Province

湖北省土家族妇女生育率的影响因素分析

The fertility rate is the number of children a woman can expect to have .

生育率是一个女性预计会生下的孩子数。

On norm optimal control problems of FEMALE-SUM fertility rate for population systems

关于人口系统妇女总和生育率的范数最优控制问题

The Optimal Control on the Noncompetitive Fertility Rate for the Time-dependent Population Developing System

时变人口发展系统非竞争人口生育率的最优控制

Non-linear Problem of the Fertility Rate Control for Age-dependent Population Diffusion System with Distributed Observation

具分布观测的年龄相关的种群扩散系统生育率控制的非线性问题

Effect factors of oocyte fertility rate in routine in-vitro fertilization

常规IVF卵母细胞受精率影响因素的探讨

A low fertility rate and increased life expectancy are the main reasons behind the rapid aging .

出生率低和人的寿命的增长是造成加拿大人口老年化速度增快的主要原因。