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Review

Maternal-Fetal Medicine in China

Zheng, Thomas Q.1,2,3,∗; Yang, Hui-Xia4

Section Editor(s): Pan, Yang; Shi, Dan-Dan

Author Information
doi: 10.1097/FM9.0000000000000029
  • Open

Abstract

Introduction

Maternal-fetal medicine (MFM) is a new concept in China. Due to the lack of standardized training and certification, MFM is hardly considered a distinct subspecialty. As medical residency and fellowship training are being implemented in China, the practice of MFM will be gradually recognized. This review is to provide a brief introduction to the Chinese medical education and training, obstetric care structure, and management of common obstetric problems. The readers must be reminded that the information presented in this review on each topic is not complete. It only serves as a window to the vast complex of landscape of medicine in China.

Medical education in China

Chinese healthcare has evolved into a unique complex system since the founding of the People's Republic of China in 1949. To better understand the healthcare system, we briefly introduce the medical education and training which forms the foundation of obstetric practice in China.

Chinese medical students are recruited directly from high school. In the past, the length of medical education used to vary from 3 years to 8 years. After a couple of decades of experimenting with different length of medical education, it has settled on the 5-year and 8-year models. Most medical schools only offer 5-year programs. Upon graduation from a 5-year program, the medical students are awarded the bachelor degree of medicine. Some prestigious medical universities offer 8 years of medical education, but the curriculum of 8-year program is different from the counter part in the United States. In the last 3 years, the medical students enrolled in the 8-year program of Chinese medical universities are actually undergoing residency training. The graduates from the 8-year programs are awarded both a doctor of medicine degree and residency training certificates in a variety of specialties. The 8-year programs are highly competitive. To enter the 8-year program, high school seniors need to perform extremely well on the national college entrance examination.

Though the bachelor degree of medicine guarantees the entrance to medical residency training, it does not allow the graduates to secure a position in the desirable hospitals in the metropolitan areas, like the large hospitals in Beijing, Shanghai, and Guangzhou. Therefore, many graduates from 5-year bachelor programs compete hard for the entrance to the master degree programs and subsequent doctor degree programs. Both the master and doctor degree programs are 3 years long.

Obstetrics and gynecology training in China

In 2013, seven ministries of the Chinese government have issued the statement to universally implement medical residency training throughout China. Most residencies including obstetrics and gynecology were established from 2014 to 2015. The medical school graduates must go through 3 years of structured residency training before being employed by any healthcare organization as staff physicians. Minor variations may exist in some cities or regions from this model. All the residencies are 3 years long regardless of medical specialties.

During 3 years of obstetrics and gynecology (OB/GYN) residency training, all the residents are required to rotate through obstetrics, gynecology, and related subspecialties. Due to the lack of adequate clinical training in medical schools, the residents have to catch up while in their residencies. Compared to the residents in the United States, Chinese OB/GYN residents work less hours. Understandably, the residency curriculum is not well structured. From the hospital administration to attending physicians and ancillary staff, everyone is learning the new concept of residency training. Residents’ opportunities for performing surgeries and procedures are quite limited due to many factors including cultural acceptance of inexperienced residents doing surgeries and legal challenges. The physician pay is also a major factor that discourages the experienced physicians to teach residents, especially in the surgical specialties. The physician's bonus is closely tied to the financial performance. Spending time to teach during surgery will likely slowly down the surgery which negatively affects a physician's income. The minimum number of surgeries required for graduation from OB/GYN residency between China and the United States are roughly compared in Table 1.1,2 Even with a fairly low number of surgeries and procedures required for graduation, many OB/GYN residents in China are still struggling to meet the minimum requirement. Some curriculum designs slightly different from the national standard may better reflect the reality of OB/GYN practice in the region. In Beijing area, for example, 21 hysterectomies, 25 adnexal surgeries, and 100 cesarean deliveries are required during residency training, but the resident can be either the surgeon or the assistant.3

Table 1
Table 1:
Minimum number of surgical procedures required for graduation from OB/GYN residency.

With the exception of some cities, most graduates from residencies need to find employments perhaps with different hospitals. However, they will continue to work as residents until they complete the chief resident training in the hospitals where they are employed. Once completed, they are promoted to the attending physician status. Throughout their medical career, a physician may go through different ranks from a resident to attending physician, then to associate chief physician, and finally to chief physician. Usually, the chief of an obstetrical unit is in charge of the daily operation, including personnel, finance, research projects, and education for rotating students and residents. When it comes to management of a difficult clinical situation, the chief of the obstetric unit or the most senior obstetrician makes the final decision.

MFM training in China

Currently, there are no formal MFM fellowship training programs in China. Therefore, the practice of MFM is fragmented and varies from one hospital to another. Chinese MFM is usually divided into maternal medicine and fetal medicine. Maternal medicine focuses on the management of pregnancy complications or maternal comorbidities, whereas, fetal medicine is further divided into prenatal diagnosis, genetic counseling, and fetal therapy (Fig. 1). The senior obstetricians usually head the teams of maternal medicine or fetal medicine and assume the role of MFM specialists.

Figure 1
Figure 1:
Structure of Chinese fetal medicine.

Chinese obstetricians and MFM providers are not licensed to perform ultrasonography which significantly limits development of MFM in China. All the ultrasonic examinations are performed by the physicians from the ultrasound division of radiology department. Technicians are not allowed to perform ultrasonography.

Training programs for visiting physician remains the dominant training method for an obstetrician who aspires to become a specialist either in maternal medicine or fetal medicine. There are many tertiary hospitals in the major cities that provide training for physicians from other hospitals. Visiting physician training usually lasts several months to 1 year. During this kind of training, the obstetricians learn how to manage complicated obstetric problems and obtain necessary procedural skills. After the training, they return to their own hospitals to implement a new treatment program.

Obstetric providers in China

There are two medical professionals who mainly provide care for pregnant women. Obstetricians manage the entire pregnancy and pregnancy-related issues. Nurse midwives manage normal labor only. If there is any problem from labor and delivery, the midwives will immediately notify the obstetricians. Midwifery students are also directly recruited from high schools in China. After completing 3 or 4 years of midwifery education, the graduates will be recruited by the hospitals to work in the labor and delivery units. However, some midwives may not have formal midwifery education. Instead, they are converted to the midwives through on-the-job training. The midwives do not have privileges to prescribe medications. Therefore, they do not have their own clinics in China.

Structure of obstetric care

In China, most infants are born in the public hospitals. The women and infant hospitals specializing in maternity care are seen in most Chinese cities. These freestanding women and infant hospitals are staffed mostly by the obstetricians and gynecologists who provide prenatal care and deliver most Chinese infants. Complete medical and surgical specialties are not available in women and infant hospitals for inpatient and outpatient consultations. If the need for other medical services arises, for example, critical care, surgery, infectious disease, hematology, cardiology, nephrology, and neurology, the patient has to be referred or transferred to the nearby general hospitals for consultation or management.

A color-coded system was developed and gradually implemented to coordinate regional maternity care. At the first prenatal visit and during the course of pregnancy, the woman is evaluated for various risk factors using color-coded system (green, yellow, orange, pink, red, and purple) where red represents the pregnancy at the most severe risk; pink represents the pregnancy at high risk; orange represents the pregnancy at moderate risk; and green represents low-risk or normal pregnancy. The color of purple represents pregnancy complicated by infectious diseases. The pregnant women identified to have pregnancy-related complication or medical problems are recommended to go to appropriate facilities for continued care.

In the general hospitals with low patient volume, the practice of OB/GYN is usually combined. In the large women and children's hospitals, OB/GYN are often separated completely. Early pregnancies, usually before 16 weeks of gestation, can be managed by the gynecologists, although the protocol varies from different hospitals. The obstetric department can be further divided into several divisions headed by different senior obstetricians (Fig. 2). Each obstetric division may have antenatal and postpartum patients and function independently.

Figure 2
Figure 2:
Obstetric care flow in women and children's hospitals.

In the public healthcare system, the outpatient evaluation is quite limited due to the physician's time constraints. The large hospital clinics are burdened with overwhelming number of patients. It is not uncommon for an obstetrician to see over 100 patients a day. Obstetric triage, an indispensable component of obstetric services in Western countries, is not available in Chinese hospitals. Therefore, the pregnant women with major complaints or diagnostic uncertainties have to be admitted to the obstetric wards for evaluation.

Labor and delivery units

In contrast to large patient volume and large inpatient wards, the labor and delivery unit is often small. For example, there are only eight delivery suites in the main campus of Guangzhou Women and Children's Hospital where over 15 000 infants are born annually. In some public hospitals, more than one patient may give birth in a large delivery suite although this practice is discouraged secondary to the concerns about infection and privacy. The laboring women usually stay at the delivery-waiting area next to the delivery suites until advanced cervical dilation is reached. There are no universally accepted criteria regarding when to move the laboring patients from the delivery-waiting area to the delivery suites. The decision is likely dependent on the laboring patient load.

In Chinese hospitals, there is no restriction on oral intake in labor and delivery units. The laboring patients can have regular diet including solid food. In the United States; however, only oral intake of clear liquids is allowed during labor. A fasting period of 6–8 hours before elective cesarean delivery is required both in China and United States.4

Many hospitals do not have fully equipped and staffed operating rooms in labor and delivery units. Occasionally, cesarean delivery has to be performed under local anesthesia in an emergency situation. Most cesarean deliveries including emergency cesarean deliveries are often performed in the main operating rooms. Lack of operating room and epidural analgesia in labor and delivery unit is fairly common in the general hospitals. However, this situation is markedly improving in many women and infant hospitals. In the exceptional cases, the rate of epidural analgesia may approach 90% in women who attempt vaginal deliveries.5

Due to limited space and staff shortage, Chinese hospitals cannot handle prolonged labor induction. Induction of labor is usually initiated in the obstetric wards by artificial rupture of membranes, intravenous (IV) infusion of oxytocin, or vaginal placement of prostaglandins. When IV infusion of oxytocin is used in obstetric wards for induction of labor, the staff needs to count drops of IV fluid to ascertain the dose of oxytocin because electronic infusion pump is not commonly used. The patient is later transferred to labor and delivery units when the labor progresses to active phase. In obstetric wards, continuous electronic fetal monitoring is not always available which constitutes a major hazard to labor induction. Most hospitals do not have central electronic fetal monitoring system.

Maternal mortality in China

As the Chinese economy and living standard improve over past few decades, maternal mortality has been rapidly decreasing. According to the official figure from the National Health Commission, the overall maternal mortality decreased from 88.8/100 000 in 1990 to 18.3/100 000 in 2018.6 However, enormous disparity exists in mortality rate across different regions in China, which closely reflects the region's economic development. For example, the mortality rate was 3/100 000–13/100 000 in the coastal areas and 193/100 000–3 511/100 000 in Tibet and some western provinces.7

In China, obstetric hemorrhage and amniotic fluid embolism, accounting for 25.3% and 15.7% of deaths, respectively, are the main causes of maternal deaths.8 In the past, the criteria for diagnosis of amniotic fluid embolism were not stringent. Many patients diagnosed with amniotic fluid embolism probably had obstetric hemorrhage initially which then developed to the stage of disseminated intravascular coagulation. In 2018, more strict criteria for diagnosing amniotic fluid embolism were proposed in a Chinese expert consensus consistent with the current criteria used in the United States and the United Kingdom.9 With the new criteria in use, the number of amniotic fluid embolism is expected to decrease. In comparison, the leading cause of maternal death in the United States is cardiovascular diseases including cardiomyopathy.10

Practice difference between China and the United States

Many differences in obstetric practice exist between China and the United States. China's birth control policy has had significant impact on obstetric practice. In the era of one-child policy, the national rate of cesarean delivery was estimated to be 40% to 50%, and up to 70% of cesarean rate was reported in some urban areas.11–13 With changes in national family planning policy in 2016 and especially with efforts from Chinese obstetricians and academic organizations, the rate of cesarean delivery has gradually decreased in China. For example, in the Guangzhou Women and Children's Hospital where the author (TQZ) works, the latest overall cesarean delivery rate is 32%. Some obstetric practices, such as, trial of labor after cesarean and external cephalic version that vanished in the era of one-child policy, are gradually coming back to clinical practice in China.

Management of placenta accreta spectrum in China

Cesarean hysterectomy with placenta left in situ after delivery of the fetus is generally accepted as the standard operative technique in the management of placenta accreta spectrum in the United States.14,15 In China, however, hysterectomy is infrequently performed for management of placenta accreta. Most obstetricians and patients prefer uterine preservation regardless of placenta accrete, increta, or percreta. Chinese obstetricians have developed a variety of operative techniques in preserving uterus while removing placenta at the same time.16–18 Uterine devascularization is the critical step in uterine preservation. Before attempting placental removal, uterine blood flow has to be effectively controlled. Reconstruction of lower uterine segment has to be performed if large uterine defect is encountered after removal of invaded placental tissue. In extreme cases, the uterine body has to be reattached, because the invading placental tissue has destroyed the entire lower uterine segment including the anterior and posterior uterine wall.18 Operative outcomes of uterine preservation surgeries appear comparable to hysterectomy with reasonably low blood loss. Successful uterine preservation rates were reported to be over 90% for patients with the placenta accreta spectrum.16,17 If the uterine preservation procedure fails to control the hemorrhage or the uterus is damaged beyond repair, of course, hysterectomy needs to be performed.

Management of placenta accreta spectrum in China and the United States represents two extremes of different approaches. Due to language barriers, vast Chinese experiences in uterine preservation have been rarely reported in the major influential journals. Currently, there are no convincing data from randomized clinical trials to guide the management of placenta accreta spectrum. With large population in China, conducting randomized clinical trials in this area can become a reality.

Fetal viability issues

Pregnancy loss either before 28 weeks of gestation or with fetus less than 1 000 grams is defined as abortion in China. Spontaneous abortion (SAB) before 13 weeks of gestation is termed early SAB. SAB between 13 weeks and 28 weeks is termed late-term SAB. Preterm birth is called when the birth occurs between 28 weeks and 37 weeks of gestation.19 If major congenital anomalies are identified in the fetus, pregnancy termination can be performed based on the patient's request. The pregnancy cannot be terminated after 28 weeks for a minor fetal anomaly in China.

Periviable birth is defined as delivery occurring from 20 0/7 weeks to 25 6/7 weeks of gestation in the United States.20,21 At 23 weeks to 26 weeks of gestation; however, most tertiary hospitals in the United States choose aggressive management of preterm labor.20,21

The gestational threshold for fetal viability is set at 28 weeks of gestation in China. Understandably, management of abortion and preterm birth in China is markedly different from the United States at 23–28 weeks of gestation during which the patient and her family play an important role in decision making regarding the medical management. Some patients may choose not to intervene and allow the nature to take its course. However, many patients may desire all the interventions possible to rescue the pregnancies and fetuses.

In the United States, all the newborns are eligible for health coverage. The parents are not paying the medical expenses associated with neonatal resuscitation and subsequent therapies. Whereas in China, the expenses incurred from preterm birth can be a formidable barrier for many families. Significant neurological morbidity associated with very early birth is also a major concern to many Chinese parents. Therefore, therapeutic intervention at very early gestational age has to be modified based on the individual situation.

Management of preterm labor in China

Antenatal corticosteroid is considered the most beneficial therapy for the improvement of neonatal outcomes in patients with preterm birth. A single course of dexamethasone given intramuscularly is widely used in China in patients with preterm labor between 24 weeks and 37 weeks of gestation.22 Betamethasone commonly used in the United States is not available in China. Magnesium sulfate for fetal neuroprotection is also used, but the standard treatment regimen has not been established in China.

The widespread use of tocolytic agents is concerning in China. Euphemism for the use of tocolytics is baotai or antai in Chinese which sounds so comforting, and makes tocolytics appear irresistible. Even though maintenance therapy with tocolytics has not been proven effective for preventing preterm birth and improving neonatal outcomes,23 prolonged tocolytic therapy is widely used in Chinese hospitals. Some providers even use tocolytics to treat threatened abortion at much earlier gestation. Progesterone is also wildly used for vaginal bleeding associated with early pregnancy.

Selection of tocolytic agents is also a concern. Although calcium channel blockers and nonsteroidal anti-inflammatory drugs are available and easy to use, many institutions elect to use ritodrine as first-line tocolytic agent while terbutalineis not easily available. Many obstetricians are not aware that ritodrine was withdrawn from the US market due to maternal side effects. Atosiban therapy is also widely used in China.

Management of hypertensive disorders

In antenatal wards, pregnant patients with hypertensive disorders are often hospitalized and given magnesium sulfate for prolonged period of time. Although the mechanism of magnesium sulfate in preventing seizure is unclear,24 many obstetricians in China believe magnesium sulfate relieves vasoconstriction associated with preeclampsia.

Sedatives, such as diazepam, are frequently used in the management of hypertensive disorders in China.25 For example, diazepam 2.5–5 mg given orally every 8 hours or 5 mg given at bedtime are common regimens for hospitalized patients. Sedatives are believed to relieve patient's anxiety, lower blood pressure, and prevent seizures. In patients with eclampsia, in addition to the use of magnesium sulfate, diazepam 10 mg IV or intramuscular is also used. Some hospitals may use a combination of meperidine, promethazine, and chlorpromazine to manage eclamptic seizures. In Western countries, benzodiazepines and phenytoin are used only as antiepileptic treatment if magnesium sulfate is contraindicated or unavailable.24

For severely elevated blood pressure, IV hydralazine and IV labetalol are considered first-line therapies,26 but IV or oral hydralazine is not available in China. Supplies of IV labetalol are not reliable either. Therefore, oral nifedipine is the most commonly used first-line therapy for severely elevated blood pressure. If nifedipine fails to control the blood pressure, next step of management varies from one hospital to another. Obstetricians have to resort to a variety of other antihypertensive medications available in their hospitals including nitroglycerine, nitroprusside, phentolamine, nicardipine, nimodipine, esmolol, or urapidil. In outpatient and inpatient setting, oral labetalol, and oral nifedipine are commonly used to manage hypertension in pregnancy. Methyldopa is not available in China.

Alloimmunization

Anti-D immune globulin has been widely used in the United States and other Western Countries for many decades which contributes to significant reduction of red cell alloimmunization in developed countries. It is given to unsensitized RhD negative women at 28 weeks of gestation and within 72 hours after birth.27 The American College of Obstetrics and Gynecology also recommends that RhD immune globulin be given to RhD negative women when performing amniocentesis or chorionic villus sampling, external cephalic version, and uterine evacuation for molar pregnancy. It is also recommended to give to RhD negative women who have SAB, medical or surgical termination of pregnancy, ectopic pregnancy, antenatal hemorrhage after 20 weeks of gestation, abdominal trauma, and fetal death in the second or third trimester. The dose of anti-D immune globulin can be adjusted based on gestational age, for example, 50–120 micrograms before 12 weeks of gestation and 300 micrograms after 12 weeks of gestation.27

There are many ethnic groups in China with Han Chinese accounting for 91.51% in Mainland based on the data from the Sixth National Census conducted in 2010.28 Among Han Chinese, Rh negative population is only 0.34%.29 In some minority groups, up to 5% can be Rh-negative. Even though the prevalence of Rh-negative population is low, Rh hemolytic disease of the fetus and newborn is still an important cause of pregnancy complications because of the population of nearly 1.4 billion people in China.30 There is no prophylaxis program in China to prevent hemolytic disease of fetus and newborn mainly because anti-D immune globulin is not available. For those pregnant women with Rh-negative status, they often try to obtain anti-D immune globulin from other sources, for example, drug stores in Hong Kong (China) or sellers on internet. Administering anti-D immune globulin obtained from nonofficial channels is a gray area and may cause legal problems.

As genetic testing becomes increasingly available, targeted administration of anti-D immune globulin to RhD negative women has been proposed. Testing of fetal Rh status can be done through analysis of cell-free DNA in maternal plasma. If the fetus is Rh D negative, anti-D immune globulin can be avoided.27 However, with such a high prevalence of RhD positive population in China, the chance of having RhD negative fetus is low. Therefore, selective administration of RhD immune globulin based on fetal RhD status is unlikely to be cost effective in China. Additionally, the rate of inconclusive results of cell-free DNA is also a concern.

Prenatal care in China

The items in prenatal care package reflect vast difference in economic development in different areas. It is recommended that pregnant women receive prenatal care at 6–13 weeks, 14–19 weeks, 20–24 weeks, 24–28 weeks, 30–32 weeks, 33–36 weeks, and 37–41 weeks, with a total of seven visits for a normal pregnancy. The laboratory tests are classified as routine tests and optional tests. Each institution may decide its own prenatal test panel based on local economic situation, patient's financial capability, and risk factors for certain conditions.31

In general, Chinese obstetricians tend to order more laboratory tests (Table 2). For a normal pregnancy without any complications, liver and renal function panels are routinely performed. At least four ultrasound examinations may be done in addition to nuchal translucency screening. In the United States, only one or two ultrasound may be needed for a normal pregnancy. In China, nonstress test and Doppler velocity are routinely performed between 37 and 41 weeks.31 Some institutions may begin nonstress test and Doppler velocimetry at 34 weeks. Home monitoring devices for fetal heart rate are also approved for widespread use in China.

Table 2
Table 2:
Practice difference between China and the United States.

Funding

None.

Conflicts of Interest

None.

References

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Keywords:

Education; Internship and residency; Maternal fetal medicine; Medical; Obstetric care; Prenatal care

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