The number of American women who gave birth last year fell precipitously over 2019, as provisional government data shows a national baby bust getting worse during the coronavirus pandemic.

A new report from the National Center for Health Statistics at the Centers for Disease Control and Prevention (CDC) found births in the United States declined 4 percent between 2019 and 2020, the steepest annual decline since 1973.

But there is evidence that even before the pandemic struck, birth rates were on pace for a steep decline: Birth rates dropped in every month of 2020, compared to 2019 — including in January, before the pandemic struck, and in the early months of a pandemic, well after parents would have chosen to conceive.

Most of the largest declines in birth rates, however, came in December, November and October, about nine months after the pandemic began and a sign that the crisis may have delayed some parents’ decisions to have children. 

Just over 3.6 million births occurred in 2020, according to the preliminary data, which covers all but a small fraction of reported births in a few states. That is nearly 150,000 fewer births than occurred during 2019 and about 700,000 fewer births than occurred in 2007, the year in which births reached a record high.

The preliminary tally represents the steepest one-year decline in births since the first year in which members of Generation X were born and the ninth-fastest drop since records began. That puts the coronavirus pandemic on par with societal catastrophes like the Great Depression and World War II, and only slightly below the damage wrought by the Spanish Flu a century ago.

The ongoing baby bust that demographers have described in recent decades began as the average age of first-time mothers rose, and became more pronounced during the great recession more than a decade ago. Demographers have estimated that so many women have put off having children, because of financial, educational, professional or personal reasons, that there are as many as three million childless women today who might have been expected to have children by this point in their lives in earlier decades.

Today, lower birth rates are occurring across racial, ethnic and economic lines. Births among white women and Black women dropped 6 percent in the last half of 2020 compared with 2019; among Asian American women, births plummeted by 12 percentage points; and and births dropped by 5 percentage points among women of Hispanic descent.

The number of births dropped in the last half of last year in all 50 states and the District of Columbia, according to the CDC figures. Declines were just as steep in fast-growing states like Texas, Florida and Georgia as they were in states that have seen population declines in recent years, like Illinois, West Virginia and New York.