Table 1.
Baseline demographic and clinical maternal and fetal characteristics of the study population stratified by corpus luteum number
| Characteristic | Total study population (n = 201) |
0 CL (n = 8) |
1 CL (n = 142) |
> 1 CL (n = 51) |
p-value |
|---|---|---|---|---|---|
| Maternal | |||||
| Age, years | 32.2 ± 4.5 | 30.5 ± 3.9 | 32.0 ± 4.4 | 33.0 ± 4.7 | 0.25 |
| Nulliparous (n, %) | 115 (57.2) | 6 (75.0) | 68 (47.6) | 42 (82.4) | < 0.01*3 |
| Mode of conception, IVF/ICSI (n, %) | 82 (40.8) | ||||
| Frozen ET, programmed cycle | 8 (9.8) | ||||
| Frozen ET, natural cycle | 23 (28.0) | ||||
| Fresh ET | 51 (62.2) | ||||
| GA at first visit, days | 55 [51, 65] | 54 [51, 58] | 62 [52, 65] | 53 [50, 63] | 0.021*3 |
| Geographic origin (n, %) | 0.24 | ||||
| Dutch | 156 (79.2) | 6 (75.0) | 104 (75.4) | 46 (90.2) | |
| Western other | 6 (3.0) | 0 (0.0) | 5 (3.6) | 1 (2.0) | |
| Non-western | 35 (17.8) | 2 (25.0) | 29 (21.0) | 4 (7.8) | |
| Educational level (n, %) | 0.53 | ||||
| Low | 18 (9.1) | 0 (0.0) | 14 (10.1) | 4 (7.8) | |
| Middle | 65 (33.0) | 4 (50.0) | 41 (29.7) | 20 (39.2) | |
| High | 114 (57.9) | 4 (50.0) | 83 (60.1) | 27 (52.9) | |
| BMI at first visit in first trimester, measured (kg/m2) | 24.9 [22.2;28.5] | 21.4 [20.9;22.8] | 25.2 [22.6;29.2] | 23.9 [21.8;27.4] | 0.02*1 |
| MAP at first visit in first trimester, measured (mmHg) | 80.3 ± 7.2 | 80.8 (12.1) | 80.7 (6.8) | 79.6 (7.1) | 0.74 |
| Folic acid supplement use, (n, %) | 198 (98.5) | 8 (100.0) | 139 (97.9) | 51 (100.0) | 1.00 |
| Preconception initiation (n, %) | 165 (82.1) | 8 (100.0) | 110 (77.5) | 51 (100.0) | 0.001*3 |
| Alcohol consumption (n, %) | 57 (28.4) | 5 (62.5) | 42 (29.4) | 10 (19.6) | 0.04*2 |
| Smoking (n, %) | 27 (13.4) | 1 (12.5) | 21 (14.7) | 5 (9.8) | 0.68 |
| Vitamin supplement use (n, %) | 118 (58.7) | 4 (50.0) | 83 (58.5) | 31 (60.8) | 0.16 |
| First-trimester blood measurements | |||||
| 9 weeks GA, n = 111 | |||||
| Renin, pg/mL | 25 [18;33] | 10 [9;14] | 25 [18;32] | 30 [23;38] | < 0.001*1–3 |
| Prorenin, pg/mL | 277 [201;380] | 107 [75;134] | 264 [191;365] | 373 [270;443] | < 0.001*1–3 |
| Aldosterone, pg/mL | 357 [216;571] | 323 [214;469] | 297 [185;496] | 533 [348;866] | < 0.001*2,3 |
| 11 weeks GA, n = 192 | |||||
| Renin, pg/mL | 25 [17;32] | 12 [11;17] | 23.4 [17;31] | 27.0 [23;34] | 0.001*1–3 |
| Prorenin, pg/mL | 266 [206;386] | 129 [109;152] | 245.2 [204;340] | 351 [278;465] | < 0.001*1–3 |
| Aldosterone, pg/mL | 314 [222;465] | 360 [266;411] | 288 [209;398] | 454 [301;727] | 0.002*3 |
| Birth outcomes | |||||
| GA at birth, days | 39+ 1 [38+ 0;40+ 0] | 39+ 0 [38+ 6;40+ 0] | 39+ 0 [37+ 6;39+ 5] | 39+ 2 [37+ 3;40+ 4] | 0.19 |
| Birthweight, gram |
3330 [2975;3570] |
3490 [3243; 3530] |
3305 [2939; 3562] |
3335 [3045; 3682] |
0.70 |
| Placental weight, gram | 455 [387;569] | 380 [260; 426] | 438 [360; 514] | 491 [433; 563] | 0.34 |
| Fetal sex, girls (n, %) | 94 (47.7) | 3 (42.9) | 64 (46.0) | 27 (52.9) | 0.91 |
| Placenta-related complication**(n, %) | 50 (24.9) | 1 (12.5) | 39 (27.5) | 10 (19.6) | 0.38 |
| PIH | 9 (4.5) | 0 (0.0) | 7 (4.9) | 2 (3.9) | 0.79 |
| PE | 7 (3.5) | 0 (0.0) | 6 (4.2) | 1 (2.0) | 0.65 |
| FGR | 14 (7.0) | 0 (0.0) | 11 (7.7) | 3 (5.9) | 0.67 |
| PTB (iatrogenic and spontaneous) | 21 (10.4) | 1 (12.5) | 17 (11.9) | 3 (5.9) | 0.47 |
| SGA | 19 (9.5) | 0 (0.0) | 16 (11.2) | 3 (5.9) | 0.35 |
Table is partially based on previously published data [14]. Data are presented as mean ± SD or median (interquartile range). *Significance at p < 0.05. **Overlapping diagnoses. 1, statistical difference between 0 CL and 1 CL; 2, statistical difference between 0 CL and > 1 CL; 3, statistical difference between 1 CL and > 1 CL. CL = corpus luteum; GA = gestational age; ICSI = intracytoplasmic sperm injection; IVF = in vitro fertilization; ET = embryo transfer; BMI = body mass index; MAP = mean arterial pressure; PE = preeclampsia; PIH = pregnancy-induced hypertension; PTB = preterm birth; SD = standard deviation; SGA = small-for-gestational age, defined as birth weight below the 10th percentile. FGR = fetal growth restriction, defined as abdominal circumference and/or estimated fetal weight (EFW) below the 10th percentile or a more than twenty-percentile decrease on the growth curve, compared to previous measurements with at least a time span of two weeks