YearMultiparous MothersInterpregnancy Interval
Short IPIIPI of 12-35 MonthsIPI of 36 Months and over
NumberRateNumberRateNumberRate
Number & Rate of Live Births by Interpregnancy Interval and by Year,
Branch-Hillsdale-St. Joseph Health Department,
Michigan 1989-2022
19891,265  257  203.2586  463.2422  333.6
19901,124  241  214.4529  470.6354  314.9
19911,022  252  246.6464  454.0306  299.4
1992952  234  245.8418  439.1300  315.1
19931,191  253  212.4542  455.1396  332.5
19941,109  240  216.4510  459.9359  323.7
19951,079  203  188.1497  460.6379  351.3
19961,124  192  170.8524  466.2408  363.0
19971,074  207  192.7480  446.9387  360.3
19981,141  222  194.6495  433.8424  371.6
19991,133  198  174.8520  459.0415  366.3
20001,405  293  208.5617  439.1495  352.3
20011,196  237  198.2523  437.3436  364.5
20021,238  238  192.2565  456.4435  351.4
20031,261  253  200.6603  478.2405  321.2
20041,302  277  212.7599  460.1426  327.2
20051,273  250  196.4593  465.8430  337.8
20061,276  300  235.1542  424.8434  340.1
20071,316  295  224.2593  450.6428  325.2
20081,210  259  214.0529  437.2422  348.8
20091,162  255  219.4527  453.5380  327.0
20101,154  211  182.8544  471.4399  345.8
20111,113  231  207.5496  445.6386  346.8
20121,012  219  216.4420  415.0373  368.6
20131,240  232  187.1546  440.3462  372.6
20141,164  212  182.1561  482.0391  335.9
20151,126  234  207.8528  468.9364  323.3
20161,207  277  229.5513  425.0417  345.5
20171,140  231  202.6521  457.0388  340.4
20181,225  240  195.9563  459.6422  344.5
20191,112  197  177.2485  436.2430  386.7
20201,115  218  195.5525  470.9372  333.6
20211,111  200  180.0497  447.3414  372.6
2022999  213  213.2432  432.4354  354.4
        

Notes:

Rates are per 1,000 multiparous mothers.
Inter-pregnancy Interval (IPI) is the time in months between the date of last menstrual period of current pregnancy and the date of previous live birth among multiparous mothers. (This definition of IPI is sometimes called the "birth-to-birth interval, minus 9 months.")

Short IPI
The IPI is less than 12 months.

Source: 1989 Michigan Birth Certificate Registry;1990-2022 Geocoded Michigan Birth Certificate Registries.
Division for Vital Records & Health Statistics, Michigan Department of Health & Human Services