ACOG Practice Bulletin Research Articles

Peripartum thromboprophylaxis.

Prophylaxis with low-molecular-weight heparin during pregnancy is advocated for women at risk of venous thromboembolism due to its single daily dosing, expectable therapeutic response and low risk of bleeding occurrences (ACOG Practice Bulletin No. 196. American College of Obstetricians and Gynecologists. Obstet Gynecol 2018; 132: e1-17; RCOG Green-top Guideline No 37a. Royal College of Obstetricians & Gynaecologists. April 2015).

Gestational Hypertension and Preeclampsia: ACOG Practice Bulletin, Number 222.

Hypertensive disorders of pregnancy constitute one of the leading causes of maternal and perinatal mortality worldwide. It has been estimated that preeclampsia complicates 2-8% of pregnancies globally (). In Latin America and the Caribbean, hypertensive disorders are responsible for almost 26% of maternal deaths, whereas in Africa and Asia they contribute to 9% of deaths. Although maternal mortality is much lower in high-income countries than in developing countries, 16% of maternal deaths can be attributed to hypertensive disorders (). In the United States, the rate of preeclampsia increased by 25% between 1987 and 2004 (). Moreover, in comparison with women giving birth in 1980, those giving birth in 2003 were at 6.7-fold increased risk of severe preeclampsia (). This complication is costly: one study reported that in 2012 in the United States, the estimated cost of preeclampsia within the first 12 months of delivery was $2.18 billion ($1.03 billion for women and $1.15 billion for infants), which was disproportionately borne by premature births (). This Practice Bulletin will provide guidelines for the diagnosis and management of gestational hypertension and preeclampsia.

Gestational Hypertension and Preeclampsia: ACOG Practice Bulletin Summary, Number 222.

Hypertensive disorders of pregnancy constitute one of the leading causes of maternal and perinatal mortality worldwide. It has been estimated that preeclampsia complicates 2-8% of pregnancies globally (). In Latin America and the Caribbean, hypertensive disorders are responsible for almost 26% of maternal deaths, whereas in Africa and Asia they contribute to 9% of deaths. Although maternal mortality is much lower in high-income countries than in developing countries, 16% of maternal deaths can be attributed to hypertensive disorders (). In the United States, the rate of preeclampsia increased by 25% between 1987 and 2004 (). Moreover, in comparison with women giving birth in 1980, those giving birth in 2003 were at 6.7-fold increased risk of severe preeclampsia (). This complication is costly: one study reported that in 2012 in the United States, the estimated cost of preeclampsia within the first 12 months of delivery was $2.18 billion ($1.03 billion for women and $1.15 billion for infants), which was disproportionately borne by premature births (). This Practice Bulletin will provide guidelines for the diagnosis and management of gestational hypertension and preeclampsia.

Management of Genital Herpes in Pregnancy: ACOG Practice Bulletin Summary, Number 220.

Genital herpes simplex virus (HSV) infection during pregnancy poses a risk to the developing fetus and newborn. Genital herpes is common in the United States. Among 14- to 49-year-old females, the prevalence of HSV-2 infection is 15.9%. However, the prevalence of genital herpes infection is higher than that because genital herpes is also caused by HSV-1 (1). Because many women of childbearing age are infected or will be infected with HSV, the risk of maternal transmission of this virus to the fetus or newborn is a major health concern. This document has been revised to include that for women with a primary or nonprimary first-episode genital HSV infection during the third trimester of pregnancy, cesarean delivery may be offered due to the possibility of prolonged viral shedding.

Operative Vaginal Birth: ACOG Practice Bulletin Summary, Number 219.

Despite significant changes in management of labor and delivery over the past few decades, operative vaginal birth remains an important component of modern labor management, accounting for 3.3% of all deliveries in 2013 (1). Use of obstetric forceps or vacuum extractor requires that an obstetrician or other obstetric care provider be familiar with the proper use of the instruments and the risks involved. The purpose of this document is to provide a review of the current evidence regarding the benefits and risks of operative vaginal birth.

ACOG Practice Bulletin No. 206: Use of Hormonal Contraception in Women With Coexisting Medical Conditions: Correction.

ACOG Practice Bulletin No. 206: Use of Hormonal Contraception in Women With Coexisting Medical Conditions: Correction.

ACOG Practice Bulletin No. 211: Critical Care in Pregnancy.

Critical care in pregnancy relies predominantly on recommendations from nonpregnant adult critical care with only limited research available for obstetric critical care specifically. The purpose of this document is to review available evidence, propose strategies for obstetric-related critical care, and highlight the need for additional research. Much of the review will, of necessity, focus on general principles of critical care, extrapolating when possible to critical care in pregnancy and the puerperium. This Practice Bulletin is updated to include information about unique issues to pregnancy when conditions such as sepsis or acute respiratory distress syndrome (ARDS) are encountered and the obstetrician's role in the management of the critically ill pregnant woman, which is dependent upon the care setting and the intensive care unit (ICU) model used. The role of the tele-intensive care unit in the care of critically ill pregnant women also is explored.

ACOG Practice Bulletin No. 208: Benefits and Risks of Sterilization.

Female and male sterilization are both safe and effective methods of permanent contraception used by more than 220 million couples worldwide (). Approximately 600,000 tubal occlusions and 200,000 vasectomies are performed in the United States annually (2-4). For women seeking permanent contraception, sterilization obviates the need for user-dependent contraception throughout their reproductive years and provides an excellent alternative for those with medical contraindications to reversible methods. The purpose of this document is to review the evidence for the safety and effectiveness of female sterilization in comparison with male sterilization and other forms of contraception.

ACOG Practice Bulletin No. 208 Summary: Benefits and Risks of Sterilization.

Female and male sterilization are both safe and effective methods of permanent contraception used by more than 220 million couples worldwide (1). Approximately 600,000 tubal occlusions and 200,000 vasectomies are performed in the United States annually (2-4). For women seeking permanent contraception, sterilization obviates the need for user-dependent contraception throughout their reproductive years and provides an excellent alternative for those with medical contraindications to reversible methods. The purpose of this document is to review the evidence for the safety and effectiveness of female sterilization in comparison with male sterilization and other forms of contraception.

ACOG Practice Bulletin No. 207: Thrombocytopenia in Pregnancy.

Obstetricians frequently diagnose thrombocytopenia in pregnant women because platelet counts are included with automated complete blood cell counts obtained during routine prenatal screening (). Although most U.S. health care providers are trained using U.S. Conventional Units, most scientists, journals, and countries use Système International (SI) units. The laboratory results reported in U.S. Conventional Units can be converted to SI Units or vice versa by using a conversion factor. Given the conversion factor is 1.0, when converting from 10/μL to 10/L the platelet "count" does not seemingly change. Thrombocytopenia, defined as a platelet count of less than 150 × 10/L, is common and occurs in 7-12% of pregnancies at the time of delivery (). Thrombocytopenia can result from a variety of physiologic or pathologic conditions, several of which are unique to pregnancy. Some causes of thrombocytopenia are serious medical disorders that have the potential for maternal and fetal morbidity. In contrast, other conditions, such as gestational thrombocytopenia, are benign and pose no maternal or fetal risks. Because of the increased recognition of maternal and fetal thrombocytopenia, there are numerous controversies about obstetric management of this condition. Clinicians must weigh the risks of maternal and fetal bleeding complications against the costs and morbidity of diagnostic tests and invasive interventions. This Practice Bulletin is a targeted revision to reflect limited changes to information about new estimates for thrombocytopenia in pregnancy and the risk of recurrence of fetal-neonatal alloimmune thrombocytopenia in subsequent pregnancies, and to provide new information on the level of thrombocytopenia that permits regional anesthesia.

ACOG Practice Bulletin No. 205 Summary: Vaginal Birth After Cesarean Delivery.

Trial of labor after cesarean delivery (TOLAC) refers to a planned attempt to deliver vaginally by a woman who has had a previous cesarean delivery, regardless of the outcome. This method provides women who desire a vaginal delivery the possibility of achieving that goal-a vaginal birth after cesarean delivery (VBAC). In addition to fulfilling a patient's preference for vaginal delivery, at an individual level, VBAC is associated with decreased maternal morbidity and a decreased risk of complications in future pregnancies as well as a decrease in the overall cesarean delivery rate at the population level (1-3). However, although TOLAC is appropriate for many women, several factors increase the likelihood of a failed trial of labor, which in turn is associated with increased maternal and perinatal morbidity when compared with a successful trial of labor (ie, VBAC) and elective repeat cesarean delivery (4-6). Therefore, assessing the likelihood of VBAC as well as the individual risks is important when determining who is an appropriate candidate for TOLAC. Thus, the purpose of this document is to review the risks and benefits of TOLAC in various clinical situations and to provide practical guidelines for counseling and management of patients who will attempt to give birth vaginally after a previous cesarean delivery.

ACOG Practice Bulletin No. 206 Summary: Use of Hormonal Contraception in Women With Coexisting Medical Conditions.

Although numerous studies have addressed the safety and effectiveness of hormonal contraceptive use in healthy women, data regarding women with underlying medical conditions or other special circumstances are limited. The U.S. Medical Eligibility Criteria (USMEC) for Contraceptive Use, 2016 (1), which has been endorsed by the American College of Obstetricians and Gynecologists, is a published guideline based on the best available evidence and expert opinion to help health care providers better care for women with chronic medical problems who need contraception. The goal of this Practice Bulletin is to explain how to use the USMEC rating system in clinical practice and to specifically discuss the rationale behind the ratings for various medical conditions. Contraception for women with human immunodeficiency virus (HIV) (2); the use of emergency contraception in women with medical coexisting medical conditions, including obesity, (3); and the effect of depot medroxyprogesterone acetate (DMPA) on bone health (4) are addressed in other documents from the American College of Obstetricians and Gynecologists.

ACOG Practice Bulletin No. 206: Use of Hormonal Contraception in Women With Coexisting Medical Conditions.

Although numerous studies have addressed the safety and effectiveness of hormonal contraceptive use in healthy women, data regarding women with underlying medical conditions or other special circumstances are limited. The U.S. Medical Eligibility Criteria (USMEC) for Contraceptive Use, 2016 (), which has been endorsed by the American College of Obstetricians and Gynecologists, is a published guideline based on the best available evidence and expert opinion to help health care providers better care for women with chronic medical problems who need contraception. The goal of this Practice Bulletin is to explain how to use the USMEC rating system in clinical practice and to specifically discuss the rationale behind the ratings for various medical conditions. Contraception for women with human immunodeficiency virus (HIV) (); the use of emergency contraception in women with medical coexisting medical conditions, including obesity, (); and the effect of depot medroxyprogesterone acetate (DMPA) on bone health () are addressed in other documents from the American College of Obstetricians and Gynecologists.

ACOG Practice Bulletin No. 200 Summary: Early Pregnancy Loss

Early pregnancy loss, or loss of an intrauterine pregnancy within the first trimester, is encountered commonly in clinical practice. Obstetricians and gynecologists should understand the use of various diagnostic tools to differentiate between viable and nonviable pregnancies and offer the full range of therapeutic options to patients, including expectant, medical, and surgical management. The purpose of this Practice Bulletin is to review diagnostic approaches and describe options for the management of early pregnancy loss.

ACOG Practice Bulletin No. 200: Early Pregnancy Loss.

Early pregnancy loss, or loss of an intrauterine pregnancy within the first trimester, is encountered commonly in clinical practice. Obstetricians and gynecologists should understand the use of various diagnostic tools to differentiate between viable and nonviable pregnancies and offer the full range of therapeutic options to patients, including expectant, medical, and surgical management. The purpose of this Practice Bulletin is to review diagnostic approaches and describe options for the management of early pregnancy loss.

ACOG Practice Bulletin No. 198 Summary: Prevention and Management of Obstetric Lacerations at Vaginal Delivery.

Lacerations are common after vaginal birth. Trauma can occur on the cervix, vagina, and vulva, including the labial, periclitoral, and periurethral regions, and the perineum. Most of these lacerations do not result in adverse functional outcomes. Severe perineal lacerations, extending into or through the anal sphincter complex, although less frequent, are more commonly associated with increased risk of pelvic floor injury, fecal and urinary incontinence, pain, and sexual dysfunction with symptoms that may persist or be present many years after giving birth. The purpose of this document is to provide evidence-based guidelines for the prevention, identification, and repair of obstetric lacerations and for episiotomy.

ACOG Practice Bulletin No. 198: Prevention and Management of Obstetric Lacerations at Vaginal Delivery.

Lacerations are common after vaginal birth. Trauma can occur on the cervix, vagina, and vulva, including the labial, periclitoral, and periurethral regions, and the perineum. Most of these lacerations do not result in adverse functional outcomes. Severe perineal lacerations, extending into or through the anal sphincter complex, although less frequent, are more commonly associated with increased risk of pelvic floor injury, fecal and urinary incontinence, pain, and sexual dysfunction with symptoms that may persist or be present many years after giving birth. The purpose of this document is to provide evidence-based guidelines for the prevention, identification, and repair of obstetric lacerations and for episiotomy.

ACOG Practice Bulletin No. 199 Summary: Use of Prophylactic Antibiotics in Labor and Delivery.

The use of antibiotics to prevent infections during the antepartum, intrapartum, and postpartum periods is different than the use of antibiotics to treat established infections. For many years, the use of prophylactic antibiotics was thought to have few adverse consequences. Concerns about the emergence of resistant strains of common bacteria, in addition to the emergence of strains with increased virulence, have resulted in increased scrutiny of the use of antibiotics, particularly in the hospital setting. Awareness of the potential adverse effects of resistant bacterial infections on neonates has been growing. Attention has been focused on the effect of mode of delivery or early antibiotic exposure on the neonatal oral and gut microbiome, which is essential for immune development. Finally, cost is a consideration in the use and choice of prophylactic agents. The purpose of this Practice Bulletin is to present a review of clinical situations in which prophylactic antibiotics are frequently prescribed and to weigh the evidence that supports the use of antibiotics in these scenarios. This Practice Bulletin is updated to reflect a limited change to clarify and provide additional information on recommendations from recent consensus guidelines for antimicrobial prophylaxis in surgery and the prevention of surgical site infection. The following practices related to cesarean delivery include preoperative skin and vaginal cleansing, weight-based dosage for cefazolin antibiotic prophylaxis, the addition of adjunctive azithromycin antibiotic prophylaxis, and antibiotic selection and dosage for women with a penicillin allergy.

ACOG Practice Bulletin No. 197: Inherited Thrombophilias in Pregnancy.

Inherited thrombophilias are associated with an increased risk of venous thromboembolism and have been linked to adverse outcomes in pregnancy. However, there is limited evidence to guide screening for and management of these conditions in pregnancy. The purpose of this document is to review common thrombophilias and their association with maternal venous thromboembolism risk and adverse pregnancy outcomes, indications for screening to detect these conditions, and management options in pregnancy. This Practice Bulletin has been revised to provide additional information on recommendations for candidates for thrombophilia evaluation, updated consensus guidelines regarding the need for prophylaxis in women with an inherited thrombophilia during pregnancy and the postpartum period, and discussion of new published consensus guidelines from the Society for Obstetric Anesthesia and Perinatology addressing thromboprophylaxis and neuraxial anesthetic considerations in the obstetric population.

ACOG Practice Bulletin No. 196 Summary: Thromboembolism in Pregnancy.

Women who are pregnant or in the postpartum period have a fourfold to fivefold increased risk of thromboembolism compared with nonpregnant women (1, 2). Approximately 80% of thromboembolic events in pregnancy are venous (3), with a prevalence of 0.5-2.0 per 1,000 pregnant women (4-9). Venous thromboembolism (VTE) is one of the leading causes of maternal mortality in the United States, accounting for 9.3% of all maternal deaths (10).The prevalence and severity of this condition during pregnancy and the peripartum period warrant special consideration of management and therapy. Such therapy includes the treatment of acute thrombotic events and prophylaxis for those at increased risk of thrombotic events. The purpose of this document is to provide information regarding the risk factors, diagnosis, management, and prevention of thromboembolism, particularly VTE in pregnancy. This Practice Bulletin has been revised to reflect updated guidance regarding screening for thromboembolism risk and management of anticoagulation around the time of delivery.