1. It is becoming increasingly common for fathers to be primary caretakers while wives develop their careers

Here is another topic sentence with a new main idea.

Then I explain and begin developing the idea.

I vary my use of long and short sentences.

I include a hypothetical example.

Finally, I state the full results.

1. In conclusion, the advent of women in the workforce has brought great benefits to the world. 2. The pertinent question is now how quickly will all parts of the world adopt these progressive improvements.

1. 
   I repeat my opinion.
   
2. 
   Then I add a final thought/detail. Read more about conclusions here.
   

Vocabulary
What do the words in bold below mean?
It is becoming increasingly common for fathers to be primary caretakers while wives develop their careers. I believe this is because of a societal shift in gender relations and it is a positive development.
The most obvious cause of more women in the workplace is modern gender relations. As recently as the 1950s in the United States, it was the unquestioned role of women to cook, clean, and look after the children. Many progressive women began to feel that they were more than their biological prerogative and feminism movements sprouted up in the 1960s. There have been years of struggle and the wage gap is still a hotly debated issue but now most reasonable adults accept that both men and women should have equal opportunity to pursue a career.
On the whole, I believe this is a positive development because women can contribute greatly to society. Since women have come into the workforce en masse there are countless examples of high performing professionals including CEOs like Shery Sandberg, athletes like Serena Williams, and authors like Margaret Atwood. That belies the impact of millions of women performing well in the average job. A company meeting a few decades ago might have been more one-sided in its male dominated viewpoints, but now it is likely to showcase more female viewpoints. This added perspective is one key to creative thinking and greatly enhances decision-making and the resultant products and services of many companies.
In conclusion, the advent of women in the workforce has brought great benefits to the world. The pertinent question is now how quickly will all parts of the world adopt these progressive improvements.