The total fertility rate (number of children per woman) seems stubborn against attempts to raise it.
I suggest instead altering the male/female ratio, so a stable or growing population can be maintained at lower TFR. Technically, filter sperm to remove those with Y chromosomes before artificial insemination.
I suggest instead altering the male/female ratio, so a stable or growing population can be maintained at lower TFR. Technically, filter sperm to remove those with Y chromosomes before artificial insemination.