Provisional Estimates for Selected Maternal and Infant Outcomes by Month, 2019-2023

The table below presents provisional estimates for selected pregnancy characteristics and birth outcomes that may be relevant to the direct and indirect impacts of COVID-19.  Estimates are shown for each month in 2021 and 2022 and compared with data for the same period in 2020 and 2019 to identify changes. Note that COVID-19 would have had little to no impact on many of these indicators in the early months of the pandemic.

Table. Selected medical and health characteristics of births, by month of birth: United States, final 2019-2022 and provisional 2023
Table
Characteristic Month of Birth
January February March April May June July August September October November December
Mother Percent
Initiation of prenatal care
Prenatal care beginning in the 1st trimester
20231 74.82 75.22 75.92 76.92 77.12 75.82 74.92 76.52 77.02
2022 76.8 76.8 77.2 77.9 78.1 77.0 75.4 76.3 77.4 77.72 77.12 76.02
2021 77.7 78.1 78.8 79.3 79.3 78.2 76.8 77.9 78.4 78.9 79.0 77.8
2020 76.7 77.1 77.7 78.5 78.9 77.9 76.9 78.2 78.6 77.3 76.9 78.0
2019 76.5 76.9 77.4 78.4 78.3 77.3 76.4 77.5 78.2 78.6 78.3 77.5
Late or no prenatal care4
20231 7.22 7.02 7.12 6.92 6.62 6.52 6.72 6.72 7.12
2022 6.7 6.5 6.6 6.7 6.5 6.5 6.6 6.7 7.0 7.02 7.12 7.12
2021 6.1 6.0 6.0 6.1 5.9 5.9 6.2 6.3 6.7 6.7 6.6 6.8
2020 6.3 6.2 6.4 6.4 5.9 5.7 5.9 6.1 6.3 6.4 6.4 6.2
2019 6.4 6.4 6.4 6.4 6.2 6.2 6.2 6.3 6.5 6.5 6.5 6.4
Adequacy of prenatal care utilization5
Adequate plus6
20231 33.42 34.32 35.22 35.82 35.52 35.82 34.92 35.12 34.72
2022 33.1 33.3 34.3 34.9 34.9 34.5 34.2 34.0 33.9 34.52 34.12 33.92
2021 33.0 33.2 34.3 35.2 35.1 34.7 34.9 34.8 34.3 34.2 34.4 34.0
2020 36.0 36.6 36.7 34.7 32.2 31.7 32.3 32.2 31.4 32.1 32.6 33.1
2019 34.9 35.9 36.7 37.0 36.9 36.9 37.3 37.0 36.1 36.8 37.1 36.5
Adequate7
20231 40.12 40.22 40.22 40.22 40.52 39.92 40.52 40.92 40.92
2022 40.7 41.1 41.1 41.0 40.8 40.9 40.6 41.1 41.2 40.72 40.22 39.92
2021 40.9 41.5 41.8 41.3 41.3 41.3 40.9 41.1 41.3 41.4 41.0 40.6
2020 39.9 39.9 40.4 41.5 42.5 42.4 41.7 42.0 41.9 41.0 40.8 41.0
2019 40.6 40.2 40.1 40.3 40.2 39.9 39.8 40.1 40.8 40.2 39.6 39.6
Less than adequate8
20231 26.52 25.42 24.72 24.02 24.12 24.32 24.52 24.02 24.42
2022 26.2 25.6 24.6 24.1 24.2 24.7 25.2 24.8 24.9 24.92 25.72 26.22
2021 26.1 25.2 23.9 23.5 23.6 24.1 24.2 24.1 24.4 24.4 24.7 25.4
2020 24.0 23.4 22.9 23.8 25.2 25.9 26.0 25.9 26.7 27.0 26.6 25.9
2019 24.5 24.0 23.1 22.7 22.9 23.2 22.9 22.9 23.2 23.0 23.3 23.8
Cesarean delivery (total)
20231 32.22 32.22 32.42 31.82 32.42 32.82 32.0 32.63 32.22
2022 32.0 32.2 32.1 31.9 32.3 32.3 31.8 32.2 32.0 32.1 32.42 32.32
2021 31.5 32.0 32.2 32.2 31.6 32.3 32.0 32.0 32.2 31.9 32.5 32.5
2020 31.8 31.4 31.6 31.8 31.6 32.0 32.1 31.6 31.7 32.0 31.9 32.0
2019 32.0 31.6 31.3 31.8 31.7 31.4 31.9 31.5 31.2 31.8 31.7 32.1
Low-risk cesarean delivery9
20231 26.42 26.62 26.82 26.52 26.63 26.93 26.42 26.83 26.42
2022 26.0 26.3 26.4 26.4 26.6 26.5 26.1 26.3 26.1 26.3 26.43 26.62
2021 25.9 26.2 26.4 26.8 26.4 26.3 26.2 26.1 26.1 26.3 26.2 26.6
2020 25.5 25.4 25.7 26.1 26.0 26.0 26.1 26.0 25.8 26.2 25.9 25.9
2019 25.8 25.8 25.5 25.8 25.8 25.5 25.5 25.6 25.0 25.6 25.6 25.7
Infant
Total preterm10
20231 10.492 10.212 10.332 10.482 10.392 10.732 10.352 10.262 10.142
2022 10.90 10.26 10.17 10.36 10.59 10.56 10.47 9.80 9.94 10.643 10.442 10.522
2021 11.01 10.45 10.22 10.59 10.50 10.44 10.42 10.49 10.12 10.44 10.41 10.83
2020 10.53 10.42 9.84 9.83 10.09 10.21 10.17 10.05 9.63 10.16 10.00 10.23
2019 10.24 10.19 10.31 10.14 10.28 10.52 10.31 10.06 9.66 10.14 10.48 10.48
Early preterm11
20231 2.772 2.652 2.722 2.862 2.832 2.822 2.75 2.722 2.712
2022 2.90 2.68 2.64 2.79 2.93 2.86 2.77 2.60 2.72 2.852 2.712 2.702
2021 3.00 2.80 2.72 2.82 2.89 2.78 2.78 2.81 2.69 2.81 2.78 2.89
2020 2.76 2.79 2.64 2.72 2.76 2.79 2.71 2.60 2.59 2.66 2.60 2.76
2019 2.72 2.76 2.83 2.78 2.83 2.94 2.78 2.65 2.65 2.70 2.86 2.77
Late preterm12
20231 7.722 7.562 7.612 7.622 7.562 7.912 7.602 7.532 7.422
2022 8.01 7.58 7.54 7.57 7.66 7.70 7.70 7.20 7.22 7.793 7.742 7.822
2021 8.00 7.65 7.49 7.77 7.61 7.66 7.64 7.67 7.43 7.63 7.63 7.94
2020 7.77 7.63 7.20 7.10 7.32 7.43 7.46 7.45 7.03 7.50 7.40 7.47
2019 7.52 7.43 7.48 7.36 7.45 7.58 7.52 7.41 7.01 7.44 7.62 7.71
Low birthweight13
20231 8.732 8.47 8.522 8.612 8.472 8.762 8.512 8.492 8.422
2022 9.01 8.48 8.39 8.54 8.76 8.74 8.59 8.18 8.33 8.833 8.742 8.692
2021 8.77 8.41 8.20 8.45 8.42 8.38 8.54 8.49 8.44 8.72 8.61 8.81
2020 8.56 8.40 8.15 8.16 8.18 8.25 8.35 8.14 7.96 8.27 8.17 8.34
2019 8.39 8.30 8.33 8.18 8.29 8.42 8.38 8.21 7.99 8.25 8.51 8.54
Very low birthweight14
20231 1.342 1.302 1.362 1.452 1.40 1.402 1.32 1.332 1.312
2022 1.41 1.30 1.31 1.37 1.47 1.40 1.36 1.29 1.37 1.412 1.352 1.31
2021 1.45 1.39 1.36 1.41 1.42 1.36 1.37 1.36 1.32 1.38 1.38 1.39
2020 1.36 1.40 1.34 1.35 1.42 1.38 1.35 1.28 1.27 1.29 1.27 1.36
2019 1.33 1.38 1.43 1.40 1.43 1.45 1.37 1.32 1.35 1.35 1.42 1.37

— Data not available.
1Provisional data; based on 100% for 2023. See Technical Notes.
2Significant quadratic trend by year (p < 0.05).
3Significant increasing trend by year (p < 0.05).
4Prenatal care the began in the third trimester and no prenatal care.
5Based on the Adequacy of Prenatal Care Utilization Index. See references 1 and 2.
6Prenatal care beginning by the fourth month of pregnancy and including 110% or more of the recommended number of visits.
7Prenatal care beginning by the fourth month of pregnancy and including at least 80%-109% of the recommended number of visits.
8Prenatal care beginning after the fourth month of pregnancy or including less than 50% of the recommended number of visits.
9Low-risk cesarean rate is the number of singleton, term (37 or more weeks of gestation based on the obstetric estimate), cephalic, cesarean deliveries to women having a first birth per 100 women delivering singleton, term, cephalic births. For more information on method of delivery, see reference 3.
10Born prior to 37 completed weeks of gestation based on the obstetric estimate. For more information on obstetric estimate, see reference 3.
11Born prior to 34 completed weeks of gestation based on the obstetric estimate. For more information on obstetric estimate, see reference 3.
12Born between 34 and 36 completed weeks of gestation based on the obstetric estimate. For more information on obstetric estimate, see reference 3.
13Less than 2,500 grams.
14Less than 1,500 grams.

SOURCE: National Center for Health Statistics, National Vital Statistics System, Natality.

Technical Notes

The National Center for Health Statistics (NCHS) is monitoring the potential impact of Coronavirus Disease 2019 (COVID-19) on pregnant women and newborn infants through compilation of the most recent birth data available through the National Vital Statistics System. Provisional estimates of selected pregnancy characteristics and birth outcomes are shown for each month in 2021 – 2023 along with the same period in 2020 and 2019 to identify changes that could potentially be associated with the indirect and direct impacts of COVID-19. These provisional estimates may be revised as additional and updated birth records are received. Note that the COVID-19 pandemic could have little if any impact on indicators such as the number of births and the percentage of women with first trimester prenatal care for births occurring in the early months of the pandemic.

Nature and sources of data

Provisional estimates are based on all complete birth records received and processed by NCHS as of a specified cutoff date. National provisional estimates include events occurring to U.S. residents within the 50 states and District of Columbia. NCHS receives the birth records and monthly provisional occurrence counts from state vital registration systems through the Vital Statistics Cooperative Program.

Provisional data are based on monthly birth records received from the states.

Table I shows the percent completeness of the provisional data by month for the United States and each jurisdiction based on where the births occurred. The percent completeness is obtained by dividing the number of complete records from each state for each month by the corresponding expected count and multiplying by 100. Expected counts are estimated by examining trends in corresponding data over the previous three-year period to adjust the counts by state and month.  All rate estimates are for the residents of the 50 states and District of Columbia.

Table I. Natality data completeness as a percentage of monthly provisional count: United States, each state, District of Columbia, and New York City, January 2023-September 2023
Table
State 2023
2023-Jan 2023-Feb 2023-Mar 2023-Apr 2023-May 2023-Jun 2023-Jul 2023-Aug 2023-Sep
Total U.S. 100 100 100 100 100 100 100 100 99.9
Alabama 100 100 100 100 100 100 100 100 100
Alaska 100 100 100 100 100 100 100 100 99.7
Arizona 100 100 100 100 100 100 100 100 100
Arkansas 100 100 100 100 100 100 100 100 99.9
California 100 100 100 100 100 100 100 100 99.9
Colorado 100 100 100 100 100 100 100 100 100
Connecticut 100 100 100 100 100 100 99.9 100 100
Delaware 100 100 100 100 100 100 100 100 99.7
District
of Columbia
100 100 100 100 100 100 100 100 100
Florida 100 100 100 100 100 100 100 100 100
Georgia 100 100 100 100 100 100 100 100 100
Hawaii 100 100 100 100 100 100 100 100 100
Idaho 100 100 100 100 100 100 100 99.9 99.9
Illinois 100 100 100 100 100 100 100 100 100
Indiana 100 100 100 100 100 100 100 100 100
Iowa 100 100 100 100 100 100 100 100 99.9
Kansas 100 100 100 100 100 100 100 100 100
Kentucky 100 100 100 100 100 100 100 100 100
Louisiana 100 100 100 100 100 100 99.9 99.8 97.5
Maine 100 99.9 100 100 100 99.9 100 100 100
Maryland 100 100 100 100 100 100 100 100 100
Massachusetts 100 100 100 100 100 100 100 100 100
Michigan 100 100 100 100 100 100 100 100 100
Minnesota 100 100 100 100 100 100 100 100 100
Mississippi 100 100 100 100 100 100 100 100 100
Missouri 100 100 100 100 100 100 100 100 100
Montana 100 100 100 100 100 100 100 100 100
Nebraska 100 100 100 100 100 100 100 100 100
Nevada 100 100 100 100 100 100 99.9 100 99.9
New Hampshire 100 100 100 100 100 100 100 100 100
New Jersey 100 100 100 100 100 100 100 100 100
New Mexico 100 100 100 100 100 100 99.9 99.9 99.7
New York State1 100 100 100 100 100 100 100 100 100
New York City 100 100 100 100 100 100 100 100 100
North Carolina 100 100 100 100 100 100 100 100 100
North Dakota 100 100 100 100 100 100 100 100 100
Ohio 100 100 100 100 100 100 100 100 100
Oklahoma 100 100 100 100 100 100 100 100 100
Oregon 100 100 100 100 100 100 100 100 100
Pennsylvania 100 100 100 100 100 100 100 100 99.9
Rhode
Island
100 100 100 100 100 100 100 100 99.4
South
Carolina
100 100 100 100 100 100 100 100 100
South Dakota 100 100 100 100 100 100 100 100 100
Tennessee 100 100 100 100 100 100 100 100 100
Texas 100 100 100 100 100 100 100 100 100
Utah 100 100 100 100 100 100 100 100 100
Vermont 100 100 100 100 100 100 100 100 100
Virginia 100 100 100 100 100 100 100 99.9 99.9
Washington 100 100 100 100 100 100 100 100 100
West
Virginia
100 100 100 100 100 100 100 100 99.7
Wisconsin 100 100 100 100 100 100 100 100 99.9
Wyoming 100 100 100 100 100 100 100 100 100

1 Excludes New York City.

NOTE: The percent completeness is obtained by dividing the number of complete records from each state for each month by the expected count and multiplying by 100. NCHS receives the birth records and monthly provisional occurrence counts from state vital registration systems through the Vital Statistics Cooperative Program.

Computing rates

Rates are presented as per 100 births.

Accuracy of estimates

Provisional estimates are subject to some nonrandom sampling error. The monthly provisional estimates are based on data that are potentially more incomplete for the most recent months. Estimates of completion rates by month were all above 95% for the United States. However, certain states may have more delayed reporting , and it is unknown whether indicators of reproductive health may be different for these states compared with states having complete reporting.

Estimates for previously released months are revised based on new data and updates received since the previous release. As a result, the reliability of estimates for a specific month will improve with each release and estimates for previous months may change with the addition of updated data

Interpretation of changes over time

Statistical significance of trends in percentages by month was assessed using the Cochran-Armitage test, a modified chi squared test, at the 0.05 level, and indicated in the table.

Adequacy of Prenatal Care Utilization Index

The Adequacy of Prenatal Care Utilization Index (APNCU) is based on the month prenatal care began and the number of visits adjusted for gestational age (1). The number of visits is assessed by comparing the number of reported visits with the number of expected visits for a particular gestational age, based on recommendations from ACOG (1,2). Inadequate care is defined as all prenatal care that began after the fourth month of pregnancy, as well as prenatal care that included less than 50% of the recommended number of visits. Intermediate care is defined as care that began by the fourth month of pregnancy and includes 50%-79% of the recommended visits. Adequate care is defined as care that began by the fourth month and includes 80%-109% of the recommended visits. Adequate plus care is defined as care that began by the fourth month and includes 110% or more of the recommended visits. In this table, “inadequate” and “intermediate” care are combined for the category “less than adequate” care (1,2). For detailed information on other measures shown in Table, see reference 3.

Suggested citation

Osterman MJK, Valenzuela CP, Martin JA. Provisional estimates for selected maternal and infant outcomes by month, 2019-2023. National Center for Health Statistics. National Vital Statistics System. 2024.

References

  1. Kotelchuck M. An evaluation of the Kessner Adequacy of Prenatal Care Index and a proposed Adequacy of Prenatal Care Utilization Index. Am J Public Heath 84(9):1414-20.1994.
  2. Osterman MJK, Martin JA. Timing and adequacy of prenatal care in the United States, 2016 [PDF – 359 KB]. National Vital Statistics Reports, vol 67 no 3. Hyattsville, MD: National Center for Health Statistics. 2018.
  3. National Center for Health Statistics. User Guide to the 2020 Natality Public Use . Hyattsville, MD.