Table 2 Comparison of demographic and pregnancy risk factor variables between women who had ate their placenta, compared to women who did not, before and after propensity score matching. The “before” data are presented as percents and frequencies from the dataset as a whole, whereas the “after” data are the percents with 95% confidence intervals, from the propensity score frequency matched datasets that were resampled 1000 times (see methods). Data come from the Midwives Alliance of North America Statistics Project (MANA Stats), birth years 2016–2018
Before Matching | After Matching | |||||
|---|---|---|---|---|---|---|
Comparison Variable | Ate placenta n (%) | Did not eat placenta n (%) | p-value (Chi-square test) | Ate placenta % (95% CI) | Did not eat placenta % (95% CI) | p-value (Chi-square test) |
Total | n = 2065 | n = 3973 | n = 1876 | n = 1876 | ||
Midwife-identified race of mother = White | 1711 (83.7%) | 3370 (85.8%) | 0.017 | 84.4% (84.0 – 84.9) | 84.5% (83.7 – 85.4) | 0.93 |
Mother is married or partnered | 1939 (94.8%) | 3763 (95.8%) | 0.049 | 94.9% (94.7 – 95.2) | 95.1% (94.6 – 95.6) | 0.76 |
Maternal education BA/BS or more | 1109 (54.8%) | 1815 (46.5%) | < 0.001 | 53.6% (53.1 – 54.1) | 54.0% (52.9 – 55.1) | 0.82 |
Mother eligible for WIC during this pregnancy | 203 (9.9%) | 389 (9.9%) | 1.0 | 10.0% (9.6 – 10.2) | 9.9% (9.2 – 10.7) | 0.91 |
Mother eligible for Medicaid | 456 (22.3%) | 952 (24.2%) | 0.048 | 22.7% (22.3 – 23.1) | 23.1% (22.1 – 24.0) | 0.79 |
Place of birth | ||||||
home | 1375 (67.2%) | 2106 (53.6%) | < 0.001 | 65.2% (64.9 – 65.6) | 65.7% (64.4 – 67.0) | 0.73 |
birth center | 671 (32.8%) | 1822 (46.4%) | 34.8% (34.4 – 35.1) | 34.3% (33.0 – 35.6) | ||
Primary midwife credentiala | ||||||
Certified Professional Midwife | 1267 (61.9%) | 2254 (57.4%) | < 0.001 | 61.0% (60.1 – 61.5) | 61.1% (59.9 – 62.4) | 0.96 |
Certified Nurse Midwife | 349 (17.1%) | 844 (21.5%) | 17.9% (17.5 – 18.1) | 17.6% (16.6 – 18.7) | ||
Other | 430 (21.0%) | 830 (21.1%) | 21.2% (20.7 – 21.5) | 21.2% (20.1 – 22.3) | ||
Pre-gravid BMI | ||||||
< 18.5 | 74 (3.6%) | 138 (3.5%) | 0.049 | 3.7% (3.5 – 3.8) | 4.0% (3.6 – 4.5) | 0.99 |
18.5—< 25 | 1286 (63.4%) | 2339 (59.8%) | 62.4% (61.9 – 62.9) | 62.0% (60.8 – 63.3) | ||
25—< 30 | 418 (20.6%) | 889 (22.7%) | 20.7% (20.3 – 21.1) | 20.8% (19.8 – 21.9) | ||
30—< 35 | 161 (7.9%) | 327 (8.4%) | 8.1% (7.8 – 8.3) | 8.1% (7.4 – 8.8) | ||
35 + | 90 (4.4%) | 220 (5.6%) | 4.5% (4.3 – 4.6) | 4.5% (4.3 – 4.6) | ||
Mother is primiparous | 645 (31.5%) | 1008 (25.7%) | < 0.001 | 30.7% (30.1 – 31.2) | 30.2% (29.0 – 31.2) | 0.75 |
If multipara, history of cesareanb | ||||||
and history of vag. birth | 52 (3.7%c) | 110 (3.8%c) | 0.068 | 3.7%c (3.5 – 4.0) | 3.8%c (3.2 – 4.4) | 0.99 |
without history of vag. birth | 42 (3.0%c) | 55 (1.9%c) | 2.8%c (2.6 – 3.1) | 2.8% (2.3 – 3.2) | ||
Mother has “significant psychosocial history”d | 695 (34.0%) | 940 (23.9%) | < 0.001 | 32.4% (31.9 – 32.9) | 31.2% (30.1 – 32.2) | 0.42 |
Mother has history of anxiety, depression of psychiatric disease, treated with drugs or inpatient therapy | 218 (10.7%) | 303 (7.7%) | < 0.001 | 14.0% (13.2 – 14.7) | 13.9% (12.7 – 15.1) | 0.92 |
Mother has history of anxiety, depression of psychiatric disease, NOT treated with drugs or inpatient therapy | 419 (20.6%) | 575 (14.7%) | < 0.001 | 23.3% (22.5 – 24.0) | 23.3% (22.1 – 24.6) | 1.0 |
mean (SD) | mean (SD) | mean (95% CI) | mean (95% CI) | |||
Maternal age | 31.0 (4.8) | 30.3 (4.9) | < 0.001e | 30.9 (30.9 – 31.0) | 30.9 (30.8 – 31.0) | 1.0 |
Gestational age, daysf | 281.4 (7.4) | 280.8 (7.7) | 0.006e | 281.3 (281.2 – 281.3) | 281.3 (281.1 – 281.5) | 1.0 |