The Most Common Birth Months by US State

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In the United States, like in most countries located in the middle latitudes of the Northern hemisphere, the most significant average number of births per day observing in September.

The map below shows the month with the highest count of births per day by US State.

When this information is interpreted into conception dates, using a 40-week pregnancy period, we see that the peak time for baby-making in the United States is December.