The country with the lowest sex ratio in the world is China. The primary reason behind the low sex ratio is due to China's one-child policy, which was implemented in 1979 to control the population growth.

Impact of One-Child Policy
The one-child policy resulted in a preference for male children in Chinese society, as they were seen as more valuable and could carry on the family name. This led to the selective abortion of female fetuses and even infanticide of baby girls. As a result, the sex ratio at birth became skewed towards males.

Current Sex Ratio
According to the World Bank, the sex ratio at birth in China was 1.1 males per female in 2019. This means that for every 100 female babies born, there were 110 male babies born.

Consequences
The imbalanced sex ratio in China has several consequences, including an increase in human trafficking, bride trafficking, and forced marriages. It has also resulted in a shortage of brides, particularly in rural areas, where families cannot afford to pay high bride prices. In addition, the gender imbalance has contributed to a rise in social problems, such as crime and violence.

Efforts to Address the Issue
The Chinese government has taken several measures to address the issue of the low sex ratio, including the abolition of the one-child policy in 2015. However, the impact of these measures is yet to be seen, and it will take several years before the sex ratio is balanced.

In conclusion, the low sex ratio in China is a result of the one-child policy, which has led to a preference for male children and the selective abortion of female fetuses. The imbalanced sex ratio has several consequences and will take time to be resolved, even after the abolition of the one-child policy.

Martinique has lowest gender ratio of 83.919 followed by Curaçao (84.340). Latvia (84.831), Lithuania (85.359) and Ukraine (85.913) is at 3rd, 4th and 5th position, respectively. In the list of top 10 countries having lowest male to female ratio, six countries are located in Europe continent, three in North America and one in Asia.

Top ten countries having more males population than females population are : Qatar, United Arab Emirates, Oman, Bahrain, Kuwait, Saudi Arabia, Maldives, Equatorial Guinea, Bhutan, Western Sahara. Qatar and United Arab Emirates has sex ratio 306.565 and 272.190 respectively. Except Equatorial Guinea and Western Sahara, which belong to Africa continent, other eight are from Asia continent.