BACKGROUND: Extreme temperature events, including extreme cold, are becoming more frequent worldwide, which might be harmful to pregnant women and cause adverse birth outcomes. We aimed to investigate the association between exposure to low ambient temperature in pregnant women and adverse birth outcomes, such as preterm birth, low birth weight, and stillbirth, and to summarize the evidence herein. METHODS: Relevant studies were searched in PubMed, Cochrane, and Embase electronic databases until November 2021. Studies involving low ambient temperature, preterm birth, birth weight, and stillbirth were included. The guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-analyses were followed to conduct this study risk of bias and methods for data synthesis. RESULTS: A total of 34 studies were included. First, pregnant women exposed to low ambient temperature had an increased risk of preterm birth (risk ratio [RR] 1.08; 95% confidence interval [CI] 1.04-1.13). Subgroup analyses revealed that exposure during late pregnancy was more likely to induce preterm birth. In addition, only pregnant women exposed to <1st percentile of the mean temperature suffered increased risk of preterm birth. Moreover, pregnant women living in medium or hot areas were more prone to have preterm births than those in cold areas when exposed to low ambient temperatures. Asians and Blacks were more susceptible to low ambient temperatures than Caucasians. Second, pregnant women exposed to low ambient temperature had an increased risk of low birth weight (RR 1.07; 95% CI 1.03-1.12). Third, pregnant women had an increased risk of stillbirth while exposed to low ambient temperature during the entire pregnancy (RR 4.63; 95% CI 3.99-5.38). CONCLUSIONS: Exposure to low ambient temperature during pregnancy increases the risk of adverse birth outcomes. Pregnant women should avoid exposure to extremely low ambient temperature (<1st percentile of the mean temperature), especially in their late pregnancy. This study could provide clues for preventing adverse outcomes from meteorological factors. REGISTRATION No. CRD42021259776 at PROSPERO ( https://www.crd.york.ac.uk/PROSPERO/ ).
Pregnancy ; Infant, Newborn ; Female ; Humans ; Pregnancy Outcome ; Premature Birth/epidemiology* ; Stillbirth/epidemiology* ; Temperature ; Pregnancy Complications

OBJECTIVES: To identify the perinatal risk factors for the occurrence of singleton apparently stillborn infants. METHODS: This was a case-control study. A total of 154 singleton neonates with gestational age ≥28 weeks and Apgar score of 0-1 who were subsequently successfully resuscitated in the Obstetrics and Gynecology Hospital of Fudan University from January 2006 to December 2015 were enrolled as the case group (apparently stillborn group). A total of 616 singleton infants born from January 2006 to December 2015 (1-minute Apgar score >1) were randomly selected in a 1:4 ratio as the control group. Univariate analysis and multivariate logistic regression were used to analyze the perinatal risk factors for the occurrence of apparently stillborn infants. RESULTS: The gestational age and birth weight in the apparently stillborn group were significantly lower than those in the control group (P<0.05). The incidences of fetal hydrops, cord prolapse, grade III meconium-stained amniotic fluid, placental abruption, breech presentation, severe pre-eclampsia, maternal general anesthesia at delivery, abnormal antenatal fetal heart monitoring and decreased fetal movement were significantly higher in the apparently stillborn group than those in the control group (P<0.05). The multivariate logistic analysis showed that the mother had general anesthesia at delivery (OR=34.520), decreased antenatal fetal movement (OR=28.168),placental abruption (OR=15.641), grade III meconium-stained amniotic fluid (OR=6.365), abnormal antenatal fetal heart monitoring (OR=5.739), and breech presentation (OR=2.614) were risk factors for the occurrence of apparently stillborn infants (P<0.05), while higher gestational age was a protective factor (OR=0.686, P<0.05). CONCLUSIONS Attention needs to be paid to mothers with abnormal prenatal fetal heart monitoring, decreased fetal movement, preterm labor, placental abruption, breech presentation, grade III meconium-stained amniotic fluid, and general anesthesia. Preparations for resuscitation should be done to rescue apparently stillborn infants.
Female ; Humans ; Infant ; Infant, Newborn ; Pregnancy ; Abruptio Placentae/epidemiology* ; Apgar Score ; Breech Presentation ; Case-Control Studies ; Placenta ; Pregnancy Complications/epidemiology* ; Risk Factors ; Stillbirth

Objective: To investigate the clinical characteristics and maternal and fetal prognosis of pregnant women with acute fatty liver of pregnancy (AFLP). Methods: The clinical data of 86 AFLP pregnant women admitted to the Third Affiliated Hospital of Guangzhou Medical University from September 2017 to August 2022 were collected, and their general data, clinical characteristics, laboratory tests and maternal and fetal outcomes were retrospectively analyzed. Results: (1) General information: the age of the 86 pregnant women with AFLP was (30.8±5.4) years, and the body mass index was (21.0±2.5) kg/m². There were 50 primiparas (58.1%, 50/86) and 36 multiparas (41.9%, 36/86). There were 64 singleton pregnancies (74.4%, 64/86) and 22 twin pregnancies (25.6%, 22/86). (2) Clinical characteristics: the main complaints of AFLP pregnant women were gastrointestinal symptoms, including epigastric pain (68.6%, 59/86), nausea (47.7%, 41/86), anorexia (46.5%, 40/86), vomiting (39.5%, 34/86). The main non-gastrointestinal symptoms were jaundice of skin and/or scleral (54.7%, 47/86), edema (38.4%, 33/86), fatigue (19.8%, 17/86), bleeding tendency (16.3%, 14/86), polydipsia or polyuria (14.0%, 12/86), skin itching (8.1%, 7/86), and 17.4% (15/86) AFLP pregnant women had no obvious symptoms. (3) Laboratory tests: the incidence of liver and kidney dysfunction and abnormal coagulation function in AFLP pregnant women was high, and the levels of blood ammonia, lactate dehydrogenase and lactic acid were increased, and the levels of hemoglobin, platelet and albumin decreased. However, only 24 cases (27.9%, 24/86) of AFLP pregnant women showed fatty liver by imageology examination. (4) Pregnancy outcomes: ① AFLP pregnant women had a high incidence of pregnancy complications, mainly including renal insufficiency (95.3%, 82/86), preterm birth (46.5%, 40/86), hypertensive disorders in pregnancy (30.2%, 26/86), gestational diabetes mellitus (36.0%, 31/86), fetal distress (24.4%, 21/86), pulmonary infection (23.3%, 20/86), disseminated intravascular coagulation (16.3%, 14/86), multiple organ dysfunction syndrome (16.3%, 14/86), hepatic encephalopathy (9.3%, 8/86), and intrauterine fetal death (2.3%, 2/86). ② Treatment and outcome of AFLP pregnant women: the intensive care unit transfer rate of AFLP pregnant women was 66.3% (57/86). 82 cases were improved and discharged after treatment, 2 cases were transferred to other hospitals for follow-up treatment, and 2 cases (2.3%, 2/86) died. ③ Neonatal outcomes: except for 2 cases of intrauterine death, a total of 106 neonates were delivered, including 39 cases (36.8%, 39/106) of neonatal asphyxia, 63 cases (59.4%, 63/106) of neonatal intensive care unit admission, and 3 cases (2.8%, 3/106) of neonatal death. Conclusions: AFLP is a severe obstetric complication, which is harmful to mother and fetus. In the process of clinical diagnosis and treatment, attention should be paid to the clinical manifestations and laboratory tests of pregnant women, early diagnosis and active treatment, so as to improve maternal and fetal outcomes.
Pregnancy ; Infant, Newborn ; Female ; Humans ; Adult ; Retrospective Studies ; Premature Birth/epidemiology* ; Pregnancy Complications/diagnosis* ; Fatty Liver/diagnosis* ; Fetal Death ; Stillbirth

Objective: To analyze the ultrasonic manifestations, clinical features, high risk factors and key points of pregnancy management in prenatal diagnosis of umbilical artery thrombosis (UAT). Methods: The data of 31 pregnant women of UAT diagnosed by prenatal ultrasonography and confirmed after birth from July 2017 to July 2022 at the Women's Hospital, Zhejiang University School of Medicine were retrospectively analyzed, including the maternal characteristics, pregnancy outcomes and fetal complications. In addition, the baseline data and pregnancy outcomes were compared in 21 patients who continued pregnancy after diagnosis of UAT. Of the 21 UAT cases that continued pregnancy, 10 cases were treated with low molecular weight heparin (LMWH; LMWH treatment group), while the other 11 patients had expectant treatment(expectant treatment group). Results: The age of the 31 pregnant women was (30.2±4.7) years, of which 5 cases (16%,5/31) were advanced age pregnant women. The gestational age at diagnosis was (32.9±4.0) weeks, and the gestational age at termination of pregnancy was (35.6±2.9) weeks. In 31 fetuses with UAT, 15 cases (48%) had fetal distress, 11 cases (35%) had fetal growth restriction, and 3 cases (10%) had intrauterine stillbirth. There were 28 cases of live births, including 26 cases by cesarean section and 2 cases by vaginal delivery. There were also 3 stillbirths, all delivered vaginally. Four neonates had mild asphyxia and two newborns had severe asphyxia. Among the 31 cases, 10 cases were terminated immediately after diagnosis, the gestational age at diagnosis was (35.9±2.9) weeks. Another 21 pregnancies continued, and their gestational age at diagnosis was (31.4±3.7) weeks. The median prolonged gestational age in LMWH treatment group was 7.9 weeks (4.6-9.4 weeks), and all were live births. The median prolonged gestational age in the expectant treatment group was 0.6 weeks (0.0-1.0 weeks), and 2 cases were stillbirths. There was a statistically significant difference in prolonged gestational age (P=0.002). Conclusions: Ultrasound is the preferred method for prenatal detection of UAT. Clinicians need to be vigilant for UAT when a newly identified single umbilical artery is detected by ultrasound in the second or third trimesters. The decision to continue or terminate the pregnancy depends on the gestational age and the condition of fetus. Attention should be paid to fetal movements as the pregnancy continues. The treatment of LMWH as soon as possible after diagnosis of UAT may improve the pregnancy outcome.
Pregnancy ; Infant, Newborn ; Female ; Humans ; Adult ; Infant ; Stillbirth ; Cesarean Section ; Umbilical Arteries/diagnostic imaging* ; Asphyxia ; Retrospective Studies ; Heparin, Low-Molecular-Weight/therapeutic use* ; Pregnancy Outcome ; Fetal Growth Retardation/therapy* ; Ultrasonography, Prenatal/methods* ; Gestational Age

OBJECTIVE: To assess the value of chromosomal microarray analysis (CMA) for the analysis of 824 samples from miscarriage or stillbirth. METHODS: Copy number variations (CNVs) in the abortic chorionic villi or stillbirth tissues were detected by CMA. RESULTS: All specimens were successfully analyzed, among which 381 (46.2%) were diagnosed with chromosomal abnormalities, which included 312 (81.9%) numerical abnormalities, 66 (17.3%) structural abnormalities and 3 (0.8%) uniparental disomies. Among numerical chromosomal abnormalities, aneuploidies was most common (92.0%), with trisomy 16 and 45,X accounting for 41 (13.1%) and 63 (20.2%) of the cases, respectively. Among the 66 structural chromosomal aberrations, there were 26 (39.4%) CNVs duplications, 20 (30.3%) CNVs deletions, and 20 (30.3%) CNVs duplication and deletions. 33 CNVs were predicted as have a high chance to lead to a disease. CONCLUSION CMA is a reliable, robust, and high-resolution method for the analysis of miscarriage or stillbirth samples. Numerical aberrations, in particular chromosomal aneuploides, are the main cause for spontaneous abortions and stillbirths.
Abortion, Spontaneous ; genetics ; Chromosome Aberrations ; Chromosome Disorders ; diagnosis ; genetics ; DNA Copy Number Variations ; Female ; Humans ; Microarray Analysis ; Pregnancy ; Stillbirth ; genetics

The Schmallenberg virus (SBV) is an orthobunyavirus that causes abortions, stillbirths, and congenital defects in pregnant sheep and cattle. Inactivated or live attenuated vaccines have been developed in endemic countries, but there is still interest in the development of SBV vaccines that would allow Differentiating Infected from Vaccinated Animals (DIVA). Therefore, an attempt was made to develop novel DIVA-compatible SBV vaccines using SBV glycoproteins expressed in baculovirus. All vaccines and phosphate buffered saline (PBS) controls were prepared with adjuvant and administered subcutaneously to cattle at 6 month of age. The first trial included 2 groups of animals vaccinated with either carboxyl-terminus glycoprotein (Gc) or PBS and boosted after 2 weeks. In the second trial, 3 groups of cattle were administered either Gc, Gc and amino-terminus glycoprotein (Gn), or PBS with a booster vaccination after 3 weeks. The animals were challenged with SBV 9 days after the booster vaccination in the first study, and 3 weeks after the booster vaccination in the second study. Using a SBV Gc-specific enzyme-linked immunosorbent assay, antibodies were first detected in serum samples 14 days after the first vaccination in both trials, and peaked on days 7 and 9 after the booster in the first and second trials, respectively. Low titers of neutralizing antibodies were detected in serum from only 3/6 and 2/4 animals in the first and second trial, respectively, at 14 days after the first vaccination. The titers increased 2 to 3-fold after the booster vaccination. SBV-specific RNA was detected in the serum and selective tissues in all animals after SBV challenge independent of vaccination status. The SBV candidate vaccines neither prevented viremia nor conferred protection against SBV infection.
Animals ; Antibodies ; Antibodies, Neutralizing ; Baculoviridae ; Cattle ; Congenital Abnormalities ; Enzyme-Linked Immunosorbent Assay ; Glycoproteins ; Orthobunyavirus ; RNA ; Sheep ; Stillbirth ; Vaccination ; Vaccines ; Vaccines, Attenuated ; Vaccines, Subunit ; Viremia

BACKGROUND/AIMS: The onset of inflammatory bowel disease (IBD) usually occurs at young age, and therefore, women IBD patients experience pregnancy during their disease progression. Recently, the use of anti-tumor necrosis factor-α (anti-TNF-α) has been rapidly increasing. The aim of this study was to evaluate pregnancy related outcomes in women with IBD who were treated with anti-TNF-α during pregnancy and immunity of their children. METHODS: Korean women with IBD who had been treated with anti-TNF-α during pregnancy had been enrolled. Medical records were reviewed and a survey was performed for each patient. For the patients who agreed on additional examination for their children, children's growth, medical history and antibody to hepatitis B surface antigen (anti-HBs) titer were checked. RESULTS: All 18 patients had been diagnosed with Crohn's disease. There was not any case of preterm delivery, low birth-weight infant, congenital anomaly, nor stillbirth. All 12 children had followed the regular vaccination schedule for hepatitis B and 4 of them showed negative results for anti-HBs. After the 1 booster vaccination, all children demonstrated seroconversion. Regarding live vaccines, 4 children had bacillus Calmette-Guerin and 4 had rotavirus vaccine before 6 months, without any specific side effects. CONCLUSIONS: This was the first study of immunity of the children born from IBD women who had been treated with anti-TNF-α medication during their pregnancy. IBD women had comparable pregnancy outcomes with the general women population, suggesting that the disease activity rather than the administered medication would be more important in healthy pregnancy. Considering the history of vaccination and anti-HBs titers, immunity seems to be intact in the children.
Appointments and Schedules ; Bacillus ; Child ; Crohn Disease ; Disease Progression ; Female ; Hepatitis B ; Hepatitis B Surface Antigens ; Humans ; Infant ; Inflammatory Bowel Diseases ; Medical Records ; Necrosis ; Pregnancy ; Pregnancy Outcome ; Rotavirus ; Seroconversion ; Stillbirth ; Vaccination ; Vaccines

OBJECTIVES: Stillbirth is a common adverse pregnancy outcome that represents a distressing and traumatic event for women and their partners. The aim of this study was to identify factors associated with stillbirth in ever-pregnant women in Nepal. METHODS: This study utilized the individual women's dataset from the Nepal Demographic and Health Survey, conducted in 2016. The dependent variable of interest was whether women had at least 1 stillbirth during their lifetime. The associations between independent variables and the dependent variable of the study were analyzed using a multiple logistic regression model. RESULTS: Among 8918 ever-pregnant women aged 15-49 years, 488 had experienced at least 1 stillbirth during their lifetime, representing 5.5% of the total. After adjusting each factor for the confounding effects of other factors, maternal age, maternal education, place of residence, and sub-region remained significantly associated with having experienced stillbirth. CONCLUSIONS: Stillbirth continues to be a major problem among women, especially those with higher maternal age, those who are illiterate, and residents of certain geographical regions. To minimize stillbirth in Nepal, plans and policies should be focused on women with low education levels and residents of rural areas, especially in the western mountain and far-western hill regions.
Dataset ; Education ; Female ; Health Surveys ; Humans ; Logistic Models ; Maternal Age ; Nepal ; Pregnancy ; Pregnancy Outcome ; Pregnant Women ; Stillbirth

BACKGROUND: In pregnant women, the frequency of irregular antibodies that cause hemolytic disease of the fetus and newborn (HDFN) vary between study populations. The clinical manifestations of HDFN differ according to the specificities and degree of irregular antibodies. This study examined the frequency and nature of maternal alloimmunization and neonatal outcomes. METHODS: Pregnant women, who underwent irregular antibody screening for prenatal testing at an obstetrics clinic in a single center, were enrolled. Those who screened positive for irregular antibodies were selected as the test group, and age- and obstetrics history-matched pregnant women were selected as the control group to evaluate the pregnancy outcomes according to irregular antibodies. RESULTS: The prevalence of irregular antibodies was 2.78% (42/1,508). With the exception of an unidentified antibody, anti-D was the most frequently identified antibody, followed in order by anti-E and anti-Le(a). The rate of fetal death was higher in the test group (6/37, 16.2%) than in the control group (1/37, 2.7%) (P=0.047). Eight pregnant women had anti-C or anti-D, one woman had a stillbirth, and four living neonates developed hyperbilirubinemia. Of six pregnant women with anti-E alone or with other alloantibodies, three experienced a spontaneous abortion or stillbirth. Among the six newborns with maternal anti-Le(a) and anti-Jk(a), four developed hyperbilirubinemia, but their mothers did not experience a spontaneous abortion or stillbirth. CONCLUSION: The prevalence of unexpected antibodies among pregnant Korean women was 2.78%. A significant difference in neonatal outcomes was observed, including the death rate, prematurity, and hyperbilirubinemia, depending on the specificity of the unexpected antibody.
Abortion, Spontaneous ; Antibodies ; Female ; Fetal Death ; Fetus ; Humans ; Hyperbilirubinemia ; Infant, Newborn ; Isoantibodies ; Mass Screening ; Mortality ; Mothers ; Obstetrics ; Pregnancy ; Pregnancy Outcome ; Pregnant Women ; Prevalence ; Sensitivity and Specificity ; Stillbirth

OBJECTIVES: To analyze the causes of perinatal death and related factors from the perspective of forensic medicine, and to provide references for reducing perinatal mortality and guidance for forensic identification. METHODS: A retrospective analysis was performed on 102 cases of perinatal autopsy with clinical data from the Department of Forensic Medicine of Chongqing Medical University in 2004-2016. RESULTS: Of the 102 cases of perinatal deaths, 66 （64.71%） were neonatal deaths, 24 （23.53%） were stillborn foetuses, and 12 （11.76%） were stillbirths. Among the 66 neonatal death cases, 39 （59.09%） died within 1 d, 19 （28.79%） died within 1-3 d, and 8 （12.12%） died within >3-7 d of birth. The top 3 causes of neonatal death were pulmonary diseases, congenital malformation, umbilical cord and placental abnormalities. The causes of stillborn foetus and stillbirth were mainly umbilical cord and placental abnormalities, and intrauterine asphyxia. CONCLUSIONS Pulmonary diseases, umbilical cord and placental abnormalities, and congenital malformations are the main causes of perinatal death. In order to reduce the perinatal mortality, pre-pregnancy examination and prenatal care should be strengthened, and the knowledge of pregnancy care should be popularized.
Autopsy ; Cause of Death ; Female ; Humans ; Infant ; Infant Mortality ; Pregnancy ; Retrospective Studies ; Stillbirth