Clinical manifestations and biochemical tests
Among 248 patients with placenta implantation, the mean age was 32.58±4.79 years, and the average gestational week of diagnosis was 28.84±7.04 weeks. Compared with non-placenta previa patients, patients with placenta previa had longer treatment time (13.0 [9.0,20.0] vs. 10.0 [7.0,19.0] days, p=0.029) and earlier termination of pregnancy (31.17±7.77 vs. 33.59±5.65 weeks, p<0.001). Table 1 shows that hemoglobin, fibrinogen, and D-dimer levels (postpartum) were higher in the placenta previa group. There were no significant differences in birth weight, body mass index, systolic blood pressure, diastolic blood pressure, albumin, serum creatinine, or uric acid between the two groups.
Table 1 Basic demographic characteristics and laboratory data of patients with placenta implantation
Variate
|
All
(n=248)
|
Placenta implantation
|
p-value
|
Non-placenta previa (n=63)
|
Placenta previa (n=185)
|
General condition
|
Age (years, x±s)
|
32.26±4.53
|
31.27±5.30
|
32.58±4.79
|
0.988
|
Diagnosis time (week, x±s)
|
28.84±7.04
|
30.72±7.81
|
28.35±6.68
|
0.003
|
Treatment time (day, M (1/4,3/4) )
|
13.0(8.0,19.5)
|
10.0(7.0,19.0)
|
13.0(9.0,20.0)
|
0.029
|
Terminal pregnancy (week, x±s)
|
32.85±6.39
|
33.59±5.65
|
31.17±7.77
|
<0.001
|
Birth weight (g, x±s)
|
2684.01±649.86
|
2849.71±699.42
|
2643.51±635.66
|
0.137
|
BMI (kg/m2, M (1/4,3/4))
|
25.40(22.98,27.30)
|
24.10(22.60,26.70)
|
25.60(23.25,27.35)
|
0.124
|
SBP (mmHg, x±s)
|
114.62±12.51
|
114.79±12.24
|
114.51±12.47
|
0.762
|
DBP (mmHg, x±s)
|
70.05±9.72
|
70.89±10.68
|
69.61±9.27
|
0.364
|
Lab tests
|
Hb (g/l, x±s)
|
108.0(98.0,115.0)
|
102.0(87.0,113.0)
|
109.0(100.0,115.0)
|
0.007
|
Plt (×109/l, M (1/4,3/4))
|
216.0(186.0,250.0)
|
225.0(191.0,311.0)
|
214.0(186.0,241.0)
|
0.064
|
Fibrinogen (g/l, M (1/4,3/4))
|
3.78(3.19,4.47)
|
4.06(3.26,5.87)
|
3.66(3.19.4.25)
|
0.013
|
D-Dimer (antenatal)
(ug/ml, M (1/4,3/4))
|
1.87(1.20,3.11)
|
2.00(1.20,2.81)
|
1.86(1.20,3.20)
|
0.574
|
D-Dimer (postpartum)
(ug/ml, M (1/4,3/4))
|
3.40(1.87,5.30)
|
2.34(1.10,4.34)
|
3.59(2.15,6.15)
|
<0.001
|
Alb (g/l, x±s)
|
32.23±4.19
|
32.56±5.19
|
32.15±3.83
|
0.507
|
GPT (iu/l, x±s)
|
15.50±9.79
|
17.79±9.72
|
14.69±9.68
|
0.029
|
Scr (umol/l, x±s)
|
41.90±11.93
|
43.87±10.83
|
41.16±12.23
|
0.115
|
BUN (umol/l, x±s)
|
2.98±1.05
|
3.23±1.22
|
2.87±0.94
|
0.18
|
UA (umol/l, x±s)
|
264.55±77.13
|
259.59±82.22
|
267.30±75.35
|
0.541
|
Ca (mmol/l, x±s)
|
2.14±0.18
|
2.14±0.18
|
2.14±0.17
|
0.890
|
LDH (u/l, M (1/4,3/4))
|
214.0(168.0,377.0)
|
290.0(180.0,475.0)
|
197.0(167.0,360.0)
|
0.011
|
Hb, hemoglobin; Alb, serum albumin; Scr, serum creatinine; UA, uric acid; GPT, glutamic pyruvic transaminase; LDH, lactate dehydrogenase; Ca, calcium; Plt, platelet; BMI, body mass index; SBP, systolic pressure; DBP, diastolic pressure.
The perioperative condition in patients with or without placental previa
Compared with patients with non-placenta previa, those with placenta previa had a higher proportion of delivery history (87.0% vs. 65.1%, p<0.001), antepartum hemorrhage (34.1% vs. 20.6%, p=0.046), and uterine surgery history (80.0% vs. 27.0%, p<0.001), which also requires more active preoperative intervention. Patients with non-placenta previa also had a higher rate of induced labor (44.4% vs. 18.9%, p<0.001) (Table 2). Cesarean section (34.3% vs. 10.7%, p=0.039) and hysterectomy (28.6% vs. 3.6%, p=0.016) were the main surgical methods used in patients with placenta previa. Placenta previa was mainly induced by placenta problems (54.2% vs. 10.7%, p=0.039). In contrast, non-placenta previa was mostly induced by fetal problems (27.0 vs. 5.9%, p<0.001) (Table 3). According to the classification of placenta accreta, penetrative placenta percreta has a higher cesarean section rate and probability of hysterectomy, a greater amount of postpartum hemorrhage, and a lower menstrual recovery rate after 6 and 12 months postpartum (Table 4).
Table 2 The Perioperative basic data in placenta implantation patients with or without placenta previa
Variate
|
All
(n=248)
|
Placenta implantation
|
p-value
|
Non-placenta previa (n=63)
|
Placenta previa (n=185)
|
Delivers history
|
|
|
|
|
0(n, %)
|
46(18.5)
|
22(34.9)
|
24(13.0)
|
<0.001
|
≥1(n, %)
|
202(81.5)
|
41(65.1)
|
161(87.0)
|
<0.001
|
Antepartum hemorrhage (n, %)
|
76(30.6)
|
13(20.6)
|
63(34.1)
|
0.046
|
Miscarriages
|
0
|
58(23.4)
|
10(15.9)
|
48(25.9)
|
0.122
|
1
|
87(35.1)
|
20(31.7)
|
67(36.2)
|
0.545
|
≥2 (n, %)
|
103(41.5)
|
33(52.4)
|
70(37.8)
|
0.054
|
Uterine surgery history (n, %)
|
165(66.5)
|
17(27.0)
|
148(80.0)
|
<0.001
|
Interventional therapy
|
No (n, %)
|
108(43.5)
|
34(54.0)
|
74(40.0)
|
0.057
|
Yes, antenatal (n, %)
|
110(44.4)
|
5(7.9)
|
105(56.8)
|
<0.001
|
Yes, postpartum (n, %)
|
30(12.1)
|
24(38.1)
|
6(3.2)
|
<0.001
|
Deliver way
|
Easy labor
|
34(13.7)
|
29(46.0)
|
5(2.7)
|
<0.001
|
Caesarean
|
171(69.0)
|
14(22.2)
|
157(84.9)
|
<0.001
|
Induced labor
|
63(25.4)
|
28(44.4)
|
35(18.9)
|
<0.001
|
Table 3 The Induced labor in placenta implantation patients with or without placenta previa
Variate
|
All
(n=63)
|
Placenta implantation
|
p-value
|
Non-placenta previa (n=28)
|
Placenta previa (n=35)
|
Induced methods
|
Caesarean section (n, %)
|
15(23.8)
|
3(10.7)
|
12(34.3)
|
0.039
|
Drug induction (n, %)
|
37(58.7)
|
24(85.7)
|
13(37.1)
|
<0.001
|
Total hysterectomy (n, %)
|
11(17.5)
|
1(3.6)
|
10(28.6)
|
0.016
|
Induced labor: placental problem
|
22(34.9)
|
3(10.7)
|
19(54.2)
|
<0.001
|
Induced labor: Fetal problem
|
28(11.3)
|
17(27.0)
|
11(5.9)
|
<0.001
|
Table 4 The Basic data for patients with different grades of placenta implantation
|
Placenta Accreta
(n=109)
|
Placenta Increta
(n=112)
|
Penetrative placenta Percreta (n=27)
|
Caesarean section (n, %)
|
65(59.6)
|
80(71.4)
|
27(100)**
|
Hysterectomy (n, %)
|
4(3.7)
|
27(24.1) **
|
19(70.4) **
|
menstrual recovery
|
6 months (n, %)
|
43(38.4)
|
21(18.4) **
|
2(7.4)**
|
12 months (n, %)
|
82(73.2)
|
52(45.6) **
|
2(7.4)**
|
Postpartum hemorrhage
(Ml, M (1/4,3/4))
|
600.0
(400.0,1000.0)
|
1023.0**
(600.0,1800.0)
|
2500.0**
(1500.0,4750.0)
|
** compared with Adhesion group p<0.01
The postoperative condition in patients with or without placental previa
Patients with placenta previa had a large amount of postoperative bleeding (1000 [600, 2000] vs. 800 [500, 1500], p<0.001), so the blood transfusion rate (67% vs. 28.6%, p<0.001) was significantly increased. The Apgar score for infants born at 0 min was significantly lower for patients with placenta previa than that for non-placenta previa patients (8.60±1.79 vs. 9.40±1.09, p=0.012), and there was no significant difference between the two groups at 5 and 10 min. During the 6- and 12-months follow-up, the menstrual recovery rate of patients with placenta previa was significantly lower than that of non-placenta previa patients (22.2% vs. 39.7%, p=0.008; 48.1% vs. 71.4%, p=0.001, respectively) (Table 5).
Table 5 The Postoperative basic data in placenta implantation patients with or without placenta previa
Variate
|
All
(n=248)
|
Placenta implantation
|
p-value
|
Non-placenta previa (n=63)
|
Placenta previa (n=185)
|
Blood transfusion (n, %)
|
142(57.3)
|
18(28.6)
|
124(67.0)
|
<0.001
|
Placental classification
|
Adhesion (n, %)
|
109(44.0)
|
27(42.9)
|
82(44.3)
|
0.884
|
Implantation (n, %)
|
112(45.2)
|
21(33.3)
|
91(49.2)
|
0.029
|
Perforating (n, %)
|
27(10.9)
|
2(3.2)
|
25(13.5)
|
0.023
|
Placental residues after labor induction or delivery (n, %)
|
81(32.7)
|
48(76.2)
|
33(17.8)
|
<0.001
|
Postpartum hemorrhage (ml, M (1/4,3/4))
|
800.00
(500.00,1500.00)
|
500.00
(300.00,800.00)
|
1000.00
(600.00,2000.00)
|
<0.001
|
Menstrual recovery
|
6 months (n, %)
|
66(26.6)
|
25(39.7)
|
41(22.2)
|
0.008
|
12 months (n, %)
|
134(54.0)
|
45(71.4)
|
89(48.1)
|
0.001
|
Apgar (0 min) (x±s)
|
8.26±1.70
|
9.40±1.09
|
8.60±1.79
|
0.012
|
Apgar (5 min) (x±s)
|
9.65±0.85
|
9.47±0.61
|
9.62±0.90
|
0.442
|
Apgar (10 min) (x±s)
|
9.85±0.62
|
9.86±0.55
|
9.85±0.64
|
0.974
|
Analysis of risk factors for menstrual recovery after one year and postpartum hemorrhage
Univariate analysis showed that placenta previa correlated with menstrual recovery after one year. Logistic regression analysis showed that placental grading after delivery (hazard ratio [HR]= 0.260, 95% confidence interval [CI]: 0.135-0.530, p<0.001), blood transfusion (HR= 0.252, 95% CI: 0.089-0.718, p=0.010), placenta previa (HR= 0.291, 95% CI: 0.103-0.822, p=0.002), postpartum hemorrhage (HR= 0.307, 95% CI: 0.120-0.783, p=0.013), and diastolic blood pressure (HR=2.255, 95% CI: 1.058-4.805, p=0.035) were independent risk factors for menstrual recovery after one year in placenta accreta spectrum patients (Table 6).
Univariate analysis also showed that placenta previa correlated with postpartum hemorrhage. Logistic regression analysis showed that placental grading after delivery (HR= 3.740, 95% CI: 2.157-6.484, p<0.001), placenta previa (HR= 6.499, 95% CI: 2.699-15.651, p<0.001), D-dimer (postpartum) (HR= 2.655, 95% CI: 1.376-5.121, p=0.004), and albumin (HR= 0.503, 95% CI: 0.264-0.960, p=0.037) were independent risk factors for postpartum hemorrhage (Table 7).
Table 6 Logistic regression analysis of risk factors for menstrual recovery after one year
|
Univariate analysis
|
Multivariate analysis
|
|
HR
|
p
|
HR
|
p
|
Deliver way (Caesarean)
|
0.268(0.115,0.624)
|
0.002
|
|
|
Uterine surgery history
|
0.436(0.253,0.752)
|
0.003
|
|
|
Placental grading
|
0.242(0.153,0.381)
|
<0.001
|
0.260(0.135,0.530)
|
<0.001
|
Blood transfusion
|
0.174(0.062,0.209)
|
<0.001
|
0.252(0.089,0.718)
|
0.010
|
Placenta previa with implantation
|
0.371(0.200,0.688)
|
0.002
|
0.291(0.103,0.822)
|
0.002
|
Prenatal bleeding
|
0.574(0.334,0.985)
|
0.044
|
|
|
Postpartum hemorrhage
|
0.107(0.06,0.191)
|
<0.001
|
0.307(0.120,0.783)
|
0.013
|
Alb (32.9 g/l)
|
1.66(1.008,2.735)
|
0.047
|
|
|
Ca (2.15 mmol/l)
|
2.273(1.372,3.766)
|
<0.001
|
|
|
DBP (70 mmHg)
|
1.866(1.115,3.124)
|
0.018
|
2.255(1.058,4.805)
|
0.035
|
Table 7 Logistic regression analysis of risk factors for postpartum hemorrhage
|
Univariate analysis
|
Multivariate analysis
|
|
HR
|
p
|
HR
|
p
|
Deliver way (Caesarean)
|
5.410(2.216,13.204)
|
<0.001
|
|
|
Uterine surgery history
|
2.895(1.667,5.028)
|
<0.001
|
|
|
Placental grading
|
3.677(2.355,5.741)
|
<0.001
|
3.740(2.157,6.484)
|
<0.001
|
Placenta previa with implantation
|
5.131(2.601,10.120)
|
<0.001
|
6.499(2.699,15.651)
|
<0.001
|
Plt (216×109/l)
|
0.542(0.328,0.895)
|
0.017
|
|
|
D-dimer (postpartum) (3.40 ug/ml)
|
1.76(1.065,2.907)
|
0.027
|
2.655(1.376,5.121)
|
0.004
|
Alb (32.9 g/l)
|
0.508(0.307,0.841)
|
0.008
|
0.503(0.264,0.960)
|
0.037
|
Ca (2.15 mmol/l)
|
0.508(0.307,0.840)
|
0.008
|
|
|
Receiver operating characteristic curve analysis of placenta previa with implantation
predicting menstrual recovery after one year and postpartum hemorrhage
The area under the receiver operating characteristic curve for placenta accreta spectrum with placenta previa plus postpartum hemorrhage to predict menstrual recovery after one year was 0.783 (95% CI: 0.719-0.847, p<0.001), and the area under the receiver operating characteristic curve for placenta previa plus D-dimer to predict the presence of postpartum hemorrhage was 0.717 (95% CI: 0.653-0.780, p<0.001)(Figure1,2).