The world population increased seven times in around 200 years, reaching one billion people after hundreds of thousands of years. In November 2022, there will be eight billion people on the planet, up from seven billion in 2011. More individuals reaching reproductive age, considerable changes in fertility rates, growing urbanization, and extensive migration have all contributed to this rapid expansion. These tendencies will significantly impact future generations. One of the biggest worldwide donors to population data gathering is the UNFPA, which helps developing nations recognize and comprehend these crucial development trends.

Biological Factors Affecting Human Fertility

Introduction to Human Fertility

As fertility is essential to both biological replenishment and the survival of human society, it is viewed as a positive force in population dynamics. The age distribution of a population is influenced by fertility numbers, which also shape the population’s social, economic, and demographic traits.

Genetic Factors

Infertility in couples is frequently linked to hereditary issues. Males and females experience distinct consequences from inherited chromosomal abnormalities and gene mutations. Among them are:

– A deletion in which a chromosomal segment is absent

– Inversion, in which a chromosome is flipped

– Translocation, in which segments of a chromosome are joined to the wrong chromosome 

– Aneuploidy, in which there are either too few or too many chromosomes – Mutation, in which the DNA sequence of a gene is altered

Physiological Factors

Even with regular periods, overweight women had a lengthier time getting pregnant than non-overweight women. Additionally, linked to an increased risk of miscarriage and complications during pregnancy and delivery is being overweight. It has been demonstrated that losing weight increases the likelihood of becoming pregnant and improves fertility. While there is no one diet that has been proven to be superior to another, group fitness programmes that include exercise and nutrition guidance have been found to increase the number of pregnancies compared to weight loss advice alone.

Males who are overweight may have less-than-ideal sperm, which lowers fertility.

Being underweight may also prevent a woman from releasing an egg on a monthly basis, which can have an impact on fertility. Pregnancy issues are often linked to underweight status.  

Environmental Factors

Concerning contributory elements are Endocrine Disrupting Chemicals (EDCs). The National Institute of Environmental Health Sciences claims that these pollutants are connected to issues with the brain, immune system, development, reproduction, and other areas.

There are five primary EDCs to be mindful of:

  • BPA: Since the 1950s, a chemical known as bisphenol A has been utilized to create plastics. Some study indicates that BPAs can infiltrate into food or beverages. Use BPA-free goods, steer clear of heating plastic, eat fewer canned foods, or switch to glass storage instead of plastic to reduce your exposure to BPAs.
  • DDT: Originally used as insecticides, DDT was outlawed in the US in the 1970s. DDT is still present in the environment. The likelihood of sperm having extra chromosomes, which can cause miscarriage or birth abnormalities, rises with exposure.
  • Dioxins: Byproducts of manufacturing operations are dioxins. Foods derived from animals, such as dairy, meat, and occasionally fish, contain dioxins that are deposited in the fatty tissues of the animals and expose humans to them.
  • Heavy Metals: Usually not dangerous, heavy metals are naturally occurring in the soil. On the other hand, fertility may be impacted by excessive exposure to certain heavy metals, such as lead, mercury, and cadmium. Excessive exposure to heavy metals can result from working with metals on a regular basis or from being exposed to lead paint. You might wish to have the heavy metal content of your water analyzed if your plumbing is older.
  • Phthalates: Phthalates are added to polymers to reduce stiffness and hardness and increase flexibility and toughness. Shower curtains, building supplies, plastic blinds, and even headphone wires contain them. Certain phthalate types can also be discovered in cosmetics and fragrances. Purchase non-PVC goods and products marked “fragrance-free” or “phthalate-free” to reduce your exposure to phthalates.

World Population Trends

Historical Population Growth

History demonstrates that the world population has not always expanded at the dizzying rate that it does now. This development was specifically recognized by two historical moments:

On the one hand, there was the Neolithic Revolution, during which time agriculture and animal husbandry were developed, and humans started to rule over nature. These changes made it easier for the populace to become more sedentarized and freed up workers for other occupations, like crafts, for example. As a result, there are now about 300 million more people on the planet. 

Furthermore, the Industrial Revolution resulted in an unparalleled surge in population. The population doubled in the 19th century, tripled in the 20th century, and reached 6 billion in 2000. This exponential increase was caused by advancements in science, medicine, and the economy. Despite the COVID-19 pandemic’s effects since November 2019, the world’s population is expected to reach 8 billion people by the year 2020. In 2011, there were 7 billion people on the earth.

Current Population Statistics

The population of the globe has increased by more than three times since the middle of the 20th century. After adding 1 billion since 2010 and 2 billion since 1998, the expected population of humans worldwide increased to 8.1 billion in June 2024 from 2.5 billion in 1950.

Factors Influencing Population Growth

Birth rate: One birth for every 1000 individuals is known as the birth rate. The birth rate of a nation with 30 births per 1000 inhabitants is (30/1000) times 100 = 3%. A high fertility rate combined with a young population may lead to high birth rates.

Life expectancy: The number of years that an average person in a nation is predicted to live is known as life expectancy. It is more than 85 years in Japan and almost 53 years in the Central African Republic!

Infant mortality: Infant mortality is the mean number of babies who pass away before turning one year old.

Fertility rate: The average number of children that a woman of childbearing age is anticipated to have during her lifetime is known as her fertility rate.

Death rate: The number of deaths per 1,000 persons is known as the death rate. You need to divide this by 10 to get the percentage that it represents; this is the same formula as the one for birth rate above. The population’s age and access to healthcare determine a nation’s death rate.

Natural increase: The gap between the birth and mortality rates is due to a natural increase. A country’s natural increase is 20 per 1000 people, or 2% if its birth rate is 30 per 1000 people and its death rate is 10 per 1000 people (when the portion is multiplied by 100).

Migration: The movement of people from one place to another, typically permanently, is referred to as migration. We call these individuals migrants.

Populations can decline as a result of out-migration, often known as emigration. Immigration and immigration both contribute to a nation’s population growth.

Population Projections

According to projections, there will be 8.5 billion people on Earth by 2030, 9.7 billion in 2050, and 10.4 billion by 2100. These most recent demographic forecasts are not without uncertainty, as projections of any kind are. These numbers depend on the medium projection version, which predicts a minor increase in fertility in a number of nations with an average of fewer than two children per woman, as well as a fall in fertility for those where large families are still common. All countries are expected to see an improvement in survival prospects.


In conclusion, the world’s population reached eight billion in November 2022, driven by increased reproductive rates, changes in fertility, urbanization, and migration. Biological, physiological, and environmental factors, such as genetic abnormalities, weight issues, and exposure to endocrine-disrupting chemicals, significantly influence fertility rates.

Projections suggest the global population will reach 8.5 billion by 2030, 9.7 billion by 2050, and 10.4 billion by 2100. Understanding and addressing these factors is crucial for sustainable development and improved quality of life for future generations. The efforts of organizations like the UNFPA in providing essential data and support to developing nations are vital in navigating these demographic changes.


What are population trends and facts in india?

With a population of 1.44 billion, India, a country in South Asia, is thought to be the most populous in the world at the moment. It ranks sixth in terms of area. 

What is the most recent trend in population geography?

Population Aging and Longevity: Population ageing has become a major issue due to rising life expectancy and falling birth rates in many areas.

What are the projected implications of future population growth?

The Least Developed Regions are the source of all population expansion. According to UN projections, all six regions will see decreases in population growth between 2020 and 2100; by that time, three of the regions will be experiencing population losses, and the world will be entering a phase of worldwide population decline. 

What is the current population of India?

India has 1,441,719,852 people living there as of 2024, up 0.92% from 2023. India’s population increased by 0.81% from 2022 to 1,428,627,663 in 2023.