| Table 36.—Infant Mortality Rate for all Children Borne by Married Mothers, According to Specified Number of Reportable Pregnancies. | |
|---|---|
| REPORTABLE PREGNANCIES FOR MARRIED MOTHERS. | Infant mortality rate. |
| Total | 149.9 |
| 1 and 2 | 108.5 |
| 3 and 4 | 126.0 |
| 5 and 6 | 152.8 |
| 7 and 8 | 176.4 |
| 9 or more | 191.9 |
This tendency is shown in still another form of summary: Combinations of four or less pregnancies are, for convenience, considered as group 1, while the combinations of over four are designated group 2. The differences in rates in the two groups are notable. The infant mortality rate is much lower for the first than for the second group.
| Table 37.—Infant Mortality Rate for All Children Borne by Married Mothers, According to Specified Number of Reportable Pregnancies, by Groups | |
| REPORTABLE PREGNANCIES FOR MARRIED MOTHERS. | Infant mortality rate. |
|---|---|
| GROUP 1. | |
| 2 or less | 108.5 |
| 3 or less | 124.7 |
| 4 or less | 119.2 |
| GROUP 2. | |
| Over 4 | 171.5 |
| Over 5 | 178.8 |
| Over 6 | 183.9 |
This influence of the size of the family upon the infant mortality rate is shown in the computations giving the relative infant mortality rate for the different children borne by married mothers. The rate is most favorable for the second-born child, being 131.2. Among first born it is 143.6; for tenth or later born children 252.3.
| Table 38.—Infant Mortality Rate for All Children Borne by Married Mothers, According to the Order in which the Child was Born | |
|---|---|
| ORDER OF BIRTH. | Infant mortality rate. |
| First-born child | 143.6 |
| Second-born child | 131.2 |
| First and second born children | 138.3 |
| Third-born child | 144.2 |
| Fourth-born child | 142.0 |
| Third and fourth born children | 143.2 |
| Fifth-born child | 178.1 |
| Sixth-born child | 175.5 |
| Fifth and sixth born children | 177.0 |
| Seventh-born child | 192.1 |
| Eighth-born child | 165.4 |
| Seventh and eighth born children. | 181.5 |
| Ninth-born child | 128.2 |
| Tenth or later born child | 252.3 |
| Ninth and later born children | 201.1 |
The next table gives a further elaboration of the same data; that is, it shows the infant mortality rate where such rates are lowest and highest, respectively, according to the age of the mother at the child’s birth and the order in which the child was born. Attention is again directed to the fact that the statistics presented in this section on “Reproductive histories” are based upon the total number of reportable pregnancies; that is, in addition to the pregnancies resulting in births in 1911, all prior pregnancies of the women considered in the investigation have been included.
| Table 39.—Lowest and Highest Infant Mortality Rates, According to Age of Mother at Birth of Child and the Order in which Child was Born. | ||||
|---|---|---|---|---|
| ORDER OF BIRTH. | INFANT MORTALITY RATES, ACCORDING TO MOTHER’S AGE. | |||
| Lowest mortality. | Highest mortality. | |||
| Mother’s age. | Mortality rate. | Mother’s age. | Mortality rate. | |
| All children | 20–24 | 140.0 | Under 17 | 367.3 |
| First child | 25–29 | 92.1 | 17–19 | 190.4 |
| Second child | 25–29 | 100.3 | 17–19 | 178.6 |
| Third child | 30–39 | 106.4 | 25–29 | 160.8 |
| Fourth child | 30–39 | 122.4 | 20–24 | 155.0 |
| Fifth child | 30–39 | 105.8 | 25–29 | 236.6 |
| Sixth child | 30–39 | 164.8 | 25–29 | 171.4 |
The difference in size of family for native and foreign mothers of different ages are indicated in the next table. The total and average number of live-born children, not reportable pregnancies, are given.
| Table 40.—Total and Average Number of Live-Born Children Borne by Married Mothers Having Either a Live Birth or a Stillbirth in 1911, Classified by Nativity and Age of Mother. | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| AGE OF MOTHER AT BIRTH OF CHILD IN 1911. | ALL MARRIED MOTHERS. | NATIVE MARRIED MOTHERS. | FOREIGN MARRIED MOTHERS. | ||||||
| Total. | Live-born children. | Total. | Live-born children. | Total. | Live-born children. | ||||
| Number. | Average. | Number. | Average. | Number. | Average. | ||||
| All ages | 1,465 | 5,363 | 3.7 | 801 | 2,600 | 3.2 | 664 | 2,763 | 4.2 |
| Under 20 years | 81 | 96 | 1.2 | 62 | 70 | 1.1 | 19 | 26 | 1.4 |
| 20 to 24 years | 456 | 908 | 2.0 | 258 | 483 | 1.9 | 198 | 425 | 2.1 |
| 25 to 29 years | 389 | 1,261 | 3.2 | 196 | 536 | 2.7 | 193 | 725 | 3.8 |
| 30 to 39 years | 459 | 2,480 | 5.4 | 240 | 1,188 | 5.0 | 219 | 1,292 | 5.9 |
| 40 years and over. | 80 | 618 | 7.7 | 45 | 323 | 7.2 | 35 | 295 | 8.4 |
The next table shows all losses of pregnancy sustained by 628 mothers and the rate of loss per 1,000 births for mothers having different numbers of births or reportable pregnancies. For all mothers it was 188.4. “Loss,” as here used, means the sum of infant deaths (or deaths in first year) and stillbirths.