Analysis of the clinical characteristics of pregnant women who were hospitalized for more than 7 days after the implementation of the two-child policy

Background: To analyze the clinical characteristics of pregnant women who were hospitalized for more than 7 days after the implementation of the two-child policy. Methods: The patients who were hospitalized for more than 7 days before and after the implementation of the two-child policy were divided into a study group (after the implementation of the two-child policy) and a control group (before the implementation of the two-child policy). Data on the clinical diagnosis, rate of cesarean sections, incidence of severe placenta previa, characteristics of the ICU cases and cost of hospitalization in the two groups were analyzed and compared. Result: The proportion of patients who were hospitalized for more than 7 days after the implementation of the two-child policy increased from 28.09% to 32.44% (P < 0.05). Regarding older patients, the proportion of those with a cesarean section history increased from 15.92% to 30.15%; however, the rate of cesarean section decreased from 59.26% to 54.35% (P < 0.05). Among patients who underwent cesarean sections, the proportion of those with placental previa, postpartum hemorrhage, ART and a cesarean section history increased (P < 0.05). Compared with that in the control group, the proportion of patients with severe placenta previa in the study group increased from 3.86% to 8.73 (P < 0.05). The proportion of patients admitted to the ICU increased from 2.90% to 4.68% (P < 0.05). Conclusion: Changes in the characteristics of obstetrics inpatients after the implementation of the two-child policy are a challenge for obstetricians. Diagnosis and treatment standardization, a more detailed and comprehensive inpatient management approach, and the rational use of health resources should be promoted.

of severe placenta previa, characteristics of the ICU cases and cost of hospitalization in the two groups were analyzed and compared. Result: The proportion of patients who were hospitalized for more than 7 days after the implementation of the two-child policy increased from 28.09% to 32.44% (P < 0.05). Regarding older patients, the proportion of those with a cesarean section history increased from 15.92% to 30.15%; however, the rate of cesarean section decreased from 59.26% to 54.35% (P < 0.05). Among patients who underwent cesarean sections, the proportion of those with placental previa, postpartum hemorrhage, ART and a cesarean section history increased (P < 0.05). Compared with that in the control group, the proportion of patients with severe placenta previa in the study group increased from 3.86% to 8.73 (P < 0.05). The proportion of patients admitted to the ICU increased from 2.90% to 4.68% (P < 0.05). Conclusion: Changes in the characteristics of obstetrics inpatients after the implementation of the two-child policy are a challenge for obstetricians. Diagnosis and treatment standardization, a more detailed and comprehensive inpatient management approach, and the rational use of health resources should be promoted.

Background
On January 1st, 2016, the Chinese government issues the following statement: "The Chinese government encourages a couple to have two children; this is the two-child policy (hereinafter referred to as 'the policy')", which means the "two-child age" is around the corner. According to the China Statistical Yearbook (2017), the number of newborns in

Severe placenta previa
Severe placenta previa refers to patients who have placenta previa and whose placenta covers the previous cesarean section incision 2 . In addition to the above mentioned inclusion of inpatients with severe placental previa, this study also included some cases of placental adhesion due to a history of multiple factors such as uterine cavity surgery or infection.

Inpatients admitted to the ICU
The WHO maternal near miss criteria were used 3 .

Other Diagnoses
The diagnosis of gestational diabetes mellitus/pregestational diabetes mellitus (GDM/PGDM)and hypertensive disorder of pregnancy (HDP) were based on a Gynecology and Obstetrics reference(People's Health Publishing House, 9th Edition) 4 . Postpartum hemorrhage refers to a bleeding volume ≥ 500 ml during vaginal delivery and ≥ 1000 ml during cesarean delivery within 24 hours after delivery of the fetus 5 .

Statistical method
The data were analyzed with SPSS19.0. The measured data were expressed as the mean ±standard deviation (x±s), and a t-test was used to compare the differences between the two groups. A chi-square test was used to compare the differences in the composition ratios of the two groups, and the difference was statistically significant when P < 0.05.

2.1
The characteristics of the pregnant women who were hospitalized for more than 7 days before and after the implementation of the policy The total number of inpatients before and after the implementation of the policy was 21,003 and 10,594, respectively. The number of inpatients in the study group and the control group was 3437 and 5900, respectively, accounting for 32.44% (3437/10,594) and 28.09% (5900/21003) of all inpatients. When comparing the two groups, the proportions of older pregnant women, much older pregnant women, inpatients terminating pregnancy by vaginal delivery, inpatients terminating pregnancy by cesarean section, inpatients with severe placenta previa, inpatients using assisted reproductive technology (ART), and inpatients admitted to the ICU and the hospitalization cost were all statistically significant (P < 0.05), as shown in Table 1.
There were significant differences in the proportions of GDM/PGDM, hypertensive disorder of pregnancy, placenta previa, postpartum hemorrhage, cesarean section, severe placenta previa and termination of pregnancy by cesarean section between the two groups (P < 0.05) ( Table 2).

Characteristics of inpatients terminating pregnancy by cesarean section in the two groups
In the study group and the control group, the number of inpatients terminating pregnancy by cesarean section was 1751 and 3258, respectively. When the two groups were compared, the average age and the average hospitalization cost were higher in the study group than in the control group. The proportions of older inpatients, much older inpatients, inpatients with hypertensive disorder of pregnancy, inpatients with placenta previa, inpatients with postpartum hemorrhage, inpatients who had undergone ART treatment, inpatients with dangerous placenta previa, and inpatients terminating pregnancy by cesarean section increased significantly in the study group (P < 0.05). There were no significant differences in the proportions of inpatients with GDM/PGDM or twin pregnancy between the two groups (Table 3).

Characteristics of the patients with severe placenta previa in the two groups
There were 228 inpatients and 300 inpatients with severe placental previa in the study group and control group, respectively. There were significant differences in the average usage of plasma and of suspended red blood cells between the two groups (P < 0.05).
There were no significant differences in the average hospitalization cost or the proportion of older or most older inpatients (Table 4).

Characteristics of the inpatients admitted to the ICU in the two groups
There was a significant difference between the two groups in terms of the admission to the ICU due to obstetrical complications, such as severe placenta previa (P<0.05) ( Table   5).

Discussion
The characteristics of obstetrical inpatients in the obstetrical department of Peking University third Hospital, a critical care referral center for pregnant women in Beijing, changed after the policy was implemented. The main changes were as follows: the average age of pregnant women rose from 31.86 years to 33.04 years; the proportion of older pregnant women increased from 25.34% to 37.15%; the proportion of much older pregnant women increased from 4.58% to 7.45%; and the incidence of pregnancy complications, such as GDM/PGDM, hypertensive disorder of pregnancy, placenta previa, postpartum hemorrhage, cesarean section and dangerous placenta previa, increased in older pregnant women. Reports in the literature 6 indicate that advanced-age pregnancy has become increasingly common in both developing and developed countries.
Family planning policies, delays in pregnancy planning and the development of assisted reproductive technology have led to an increase in the number of older pregnant women.
Bekir Kahveci found that compared with pregnant women aged less than 35 years, older women show increased rates of pregnancy complications, such as hypertensive disorder of pregnancy, GDM/PGDM, and cesarean section. The incidences of placenta previa, postpartum hemorrhage, ART, cesarean section and severe placenta previa are also significantly increased compared with those before the implementation of the policy.
These factors have led to an increase in critical obstetric inpatients, longer hospital stays and higher hospitalization costs in the short term after the implementation of the policy in China.

Rate of cesarean section
In the study group, the cesarean section rate of older pregnant women rose from 15.92% to 30.15%, but the total cesarean section rate in the study group decreased from 59.26% to 54.35%. An indicated cesarean section can effectively decrease the probability of an adverse pregnancy outcome in women with complications. However, a 2015 World Health Organization statement concluded that a cesarean section rate of more than 10% does not contribute to a decline in maternal or infant mortality. In contrast, a statement issued by the WHO in 2015 indicates that when the cesarean section rate is higher than 10%, the operation can lead to more complications and deaths. 8 The rate of cesarean section in China rose rapidly from the mid-1980s to the 1990s. By the beginning of this century, the cesarean section rate was as high as 70% in multiple hospitals and even 100% in specific hospitals 9 . This situation, which is the basis of the obstetrical problems observed after the implementation of the current "policy", has caused concern in the domestic medical

Improvement of prognosis in patients with severe placenta previa
The mean number of hospitalization days decreased from 13.5 days to 11.75 days (P < 0.05) for patients with severe placenta previa. There was no difference between the two groups in terms of the mean hospital stay before surgery, but the average hospital stay after surgery decreased from 8 days to 6.66 days (P < 0.05). The average usage of plasma decreased from 711.83 ml to 445.61 ml, and the average usage of suspended red blood cells decreased from 7.36 U to 4.54 U in recent years (P < 0.05). A history of cesarean section increases the risk of severe placenta previa in the second pregnancy, and generally, the amount of cesarean section hemorrhage in placental accretion cases is more than that in other patients. In recent years, with the increasing incidence of placental accretion, Peking University third Hospital has documented many experiences in the diagnosis and treatment of placental accretion. We use the ultrasound scoring system to predict the type and severity of placental implantation 11 based on the following parameters: the placental location and thickness, whether the retroplacental hypoechoic vocal cords had disappeared, whether the bladder lines are continuous, the placental lacuna characteristics, the placental basal blood flow signals, cervical morphology, whether there are blood sinuses in the cervix, and the history of cesarean section. There are 2 points per item, and the total score is calculated. A score ≥ 5 is used to predict the adhesive type and severe type (including implantation and penetrating type, respectively) of placental accretion. When the score is ≥ 10, the possibility of a penetrating type of placental accretion is higher than that of the other two types of placental accretion.
Prenatal dynamic ultrasound examination combined with MRI provides an important reference value for evaluating the severity of placental accretion. These preoperative preparations are effective measures to reduce intraoperative bleeding and the transfusion of blood products. This approach provides important clinical guidance for preparation before termination of pregnancy. In addition, we use a balloon catheter to temporarily block the blood supply artery, which effectively reduces intraoperative bleeding, maintains clarity of the surgical field and provides an opportunity to preserve the uterus 12 . Placental hemorrhage is greatly reduced by ultrasound diagnosis for high-risk cases, the application of the balloon hemostatic method, and the cooperation of the surgical team. Multidisciplinary collaboration and effective collaboration by the MDT team reduces clinical blood consumption and improves patient prognosis.

Establishment of the criteria for admission to the ICU
The results show that the number of patients with internal and surgical diseases admitted to the ICU is lower than that in the control group, which may be related to the

Increase in hospitalization cost
Our results showed that the average hospitalization cost rose from 8766.40 yuan in the control group to 11,595.58 yuan in the study group. The average hospitalization cost increased from 10,250.77 yuan to 14,666.33 yuan for patients undergoing cesarean sections due to pregnancy complications. Although the average hospitalization cost was high for both the patients with severe placenta previa and the patients admitted to the ICU, there was no significant difference between the study group and the control group.
According to the Law of Social Insurance of China, maternity insurance is a type of social insurance that is provided by the state and society for the temporary interruption in the woman's participation in the labor force due to the birth of a child. However, some scholars have noted that [15] the scope of reimbursement is narrow and that the rate of reimbursement is too low to meet the needs of social development. Most areas of maternity insurance are reimbursed in accordance with local policies, which means that no matter how much money is spent, patients can only be reimbursed a certain amount of money. In some complicated situations during pregnancy, many more of the expenses will not be reimbursed.   Table 2 Characteristics of the older inpatients in the two groups