Why You’re Seeing More Twins Everywhere

As a Yoruba boy growing up, I remember how rare twins felt, even in Yorubaland, the fabled land of twins. In my entire school, there couldn’t have been more than seven sets. We had one pair in my class, two wiry boys with different temperaments.

Twins, to us, weren’t just siblings. They were phenomena. A living embodiment of cultural wonder and divine fingerprints. They bore names like Taiwo and Kehinde, and elders whispered old truths about who really came first. You couldn’t speak of twins without dipping into reverence and myth.

But what I didn’t realize then, what I later learned, is just how rare this “everyday miracle” truly is across the globe. And even more astounding: twins are now being born at rates the world has never seen before.

Yoruba culture has long held a unique relationship with twins. In fact, the town of Igbo-Ora in Oyo State, Nigeria, is known as the Twin Capital of the World. The incidence of twin births in the region is believed to be the highest globally. Local lore attributes this to the diet, particularly yams and other tubers. Whether that’s true or not, twins here are seen as blessings, often associated with prosperity, balance, and spiritual power.

Contrast that with many other parts of the world, where twinning has historically been interpreted with suspicion, or worse. In some cultures, twins were once thought to bring bad luck. In pre-colonial Calabar, twins were sometimes abandoned and even killed, until missionary Mary Slessor famously intervened in the 19th century, saving many and transforming social attitudes.

Yet for all this contrast in perception, a shared truth is emerging across the globe: twins are becoming far more common, and it’s not because of folklore or yams. It’s because of science, and shifting societal choices.

Between 1980 and 2015, the global twin birth rate surged by over 30%, according to research analyzing over 165 countries. Today, 1 in every 42 babies born is a twin, that’s approximately 1.6 million twins each year. This is the highest rate in recorded human history.

And this isn’t just happening in one region. The increase spans continents, from North America to Europe, from Asia to parts of sub-Saharan Africa. While genetics and ethnicity play a role (African women are more likely to have fraternal twins), the primary drivers of this boom are distinctly modern: fertility treatments and delayed childbirth.

Let’s start with medicine. Over the past few decades, fertility treatments like in vitro fertilization (IVF) and intrauterine insemination (IUI) have revolutionized reproductive health. These techniques often involve hormone therapies that stimulate the ovaries to release multiple eggs, or implanting more than one embryo to increase chances of conception. The result? A dramatic rise in fraternal twins — non-identical siblings born from two separate eggs.

In some fertility clinics, especially in earlier years when success rates were lower, multiple embryos were routinely implanted to ensure at least one successful pregnancy. Sometimes, more than one took hold. That’s why many people who give birth to triplets or quadruplets often have a little help from science.

What used to be a rare biological accident, a double blessing of nature, is now often an intentional, clinical decision. A planned miracle.

But it’s not just doctors driving this trend. It’s also women, making empowered life choices.

Across the globe, more women are choosing to have children later in life, often in their 30s and early 40s. Motivated by education, career advancement, or financial stability, this trend has had an unintended side effect. As women age, their levels of follicle-stimulating hormone (FSH) increase. This hormone, responsible for ovulation, also boosts the chances of releasing more than one egg at a time.

In plain English: A 36-year-old woman is biologically more likely to have twins than a 23-year-old, even without fertility treatments.

So, sociology and biology meet. Education leads to career planning. Career planning leads to delayed childbirth. Delayed childbirth leads, often, to multiple births.

Interestingly, while fraternal twins are on the rise, the rate of identical twins has remained constant over time. Identical twinning, where a single fertilized egg splits into two embryos, is pure chance. It happens at a steady rate of about 4 per 1,000 births, regardless of ethnicity or maternal age.

That means the real engine behind the twin boom is the predictable kind, fraternal twins, born of two eggs, shaped by hormones, age, and modern medicine.

As someone from a culture that has always revered twins, it’s humbling to witness the world catching up. What my ancestors considered mystical is now becoming mainstream. The divine has found allies in data. The spiritual has made room for science.

But in all this, one thing remains unchanged: the awe. Whether born under a thatched roof in Igbo-Ora or delivered in a high-tech suite in London or Seoul, twins still elicit gasps. They still pull crowds. They still reflect the age-old mystery of life duplicating itself.