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Risk Factors for Complications During Pregnancy

By

Raul Artal-Mittelmark

, MD, Saint Louis University School of Medicine

Reviewed/Revised Sep 2022
View PATIENT EDUCATION
Topic Resources

Risk factors for complications during pregnancy include

Hypertension

  • Chronic hypertension: Present before the pregnancy or developing before 20 weeks of pregnancy

  • Gestational hypertension: New onset of systolic and/or diastolic blood pressure (BP) ≥ 140/≥ 90 mm Hg on 2 occasions at least 4 hours apart after 20 weeks of gestation

  • Preeclampsia Preeclampsia and Eclampsia Preeclampsia is new-onset or worsening of existing hypertension with proteinuria after 20 weeks gestation. Eclampsia is unexplained generalized seizures in patients with preeclampsia. Diagnosis... read more : New onset after 20 weeks of gestation of persistent (2 episodes within 4 hours) systolic and/or diastolic BP ≥ 140/≥ 90 mm Hg OR at least 1 measurement of systolic and/or diastolic BP ≥ 160/≥ 110 mm Hg PLUS new unexplained proteinuria (> 300 mg/24 hours or urine protein/creatinine ratio ≥ 0.3 or dipstick reading of 2+; in the absence of proteinuria, new-onset hypertension with new onset of other signs of end-organ damage (eg, thrombocytopenia [platelets < 100,000/mcL], impaired liver function, renal insufficiency, pulmonary edema, new-onset headache [unresponsive to medication and not accounted for by alternative diagnoses], visual symptoms).

  • Preeclampsia with severe features: Preeclampsia with persistent (2 episodes within 4 hours) systolic and/or diastolic BP ≥ 160/≥ 110 mm Hg and/or other signs of end-organ damage

  • HELLP syndrome: A form of severe preeclampsia with hemolysis, elevated liver enzymes, and low platelet count

  • Chronic hypertension plus superimposed preeclampsia: New or worsening proteinuria or other signs of end-organ damage after 20 weeks in a woman with preexisting hypertension

  • Eclampsia: New-onset tonic-clonic, focal, or multifocal seizures not accounted for by other causes

Chronic hypertension increases risk of the following:

Before attempting to conceive, women with hypertension should be counseled about the risks of pregnancy. If they become pregnant, prenatal care should begin as early as possible. Management of chronic hypertension during pregnancy Treatment Recommendations regarding classification, diagnosis, and management of hypertensive disorders (including preeclampsia) are available from the American College of Obstetricians and Gynecologists... read more includes measurements of baseline renal function (eg, serum creatinine, blood urea nitrogen [BUN]), funduscopic examination, and directed cardiovascular evaluation (auscultation and sometimes ECG, echocardiography, or both). Each trimester, 24-hour urine protein, serum uric acid, serum creatinine, and hematocrit are measured. Ultrasonography to monitor fetal growth is done at 28 weeks and every 4 weeks thereafter. Delayed growth is evaluated with multivessel Doppler testing by a maternal-fetal medicine specialist.

If women are at high risk of preeclampsia, clinicians should prescribe low-dose aspirin (81 mg orally once a day) to be taken daily starting at 12 to 28 weeks of gestation and taken until delivery (2 Hypertension references Risk factors for complications during pregnancy include Preexisting maternal disorders Physical and social characteristics (eg, age) Problems in previous pregnancies (eg, a previous history... read more Hypertension references ).

Women with a history of preeclampsia or gestational hypertension are at a higher lifetime risk of cardiovascular events and, after delivery, should be referred for appropriate cardiovascular risk assessment and follow-up.

Hypertension references

  • 1. American College of Obstetrics and Gynecology (ACOG): ACOG Practice Bulletin, Number 222: Gestational hypertension and preeclampsia. Obstet Gynecol 133 (1):1, 2019. doi: 10.1097/AOG.0000000000003018

  • 2. ACOG Committee Opinion No. 743: Low-dose aspirin use during pregnancy. Obstet Gynecol 132 (1):e44–e52, 2018. doi: 10.1097/AOG.0000000000002708.

Diabetes

Preexisting diabetes mellitus Diabetes Mellitus in Pregnancy Pregnancy makes glycemic control more difficult in preexisting type 1 (insulin-dependent) and type 2 (non–insulin-dependent) diabetes but does not appear to exacerbate diabetic retinopathy,... read more occurs in ≥ 6% of pregnancies, and gestational diabetes occurs in about 8.5% of pregnancies. Incidence is increasing as the incidence of obesity increases.

Preexisting insulin-dependent diabetes increases the risk of the following:

The incidence of fetal macrosomia is about 50% higher in pregnant women with preexisting diabetes than in pregnant women in the general population. The incidence of perinatal mortality is also higher.

Tight glucose control before conception and during early pregnancy is essential to prevent fetal malformations.

Insulin requirements usually increase during pregnancy.

Gestational diabetes increases the risk of the following:

Gestational diabetes is routinely screened for at 24 to 28 weeks and, if women have risk factors, during the 1st trimester. Risk factors include the following:

  • Previous gestational diabetes

  • A macrosomic infant in a previous pregnancy

  • Unexplained fetal losses

  • Prepregnancy body mass index (BMI) > 30 kg/m2

  • Maternal age > 40 years

  • Family history of diabetes

  • Some races or ethnicities associated with higher rates of diabetes (eg, people with Hispanic-American, African-American, American Indian, Asian, or Pacific Islander ancestry)

Screening and confirmation of the diagnosis of gestational diabetes can be done in 1 or 2 steps:

  • 1-step test: A fasting, 75-g glucose, 2-hour oral glucose tolerance test (GTT)

  • 2-step test: A non-fasting, 50-g glucose, 1-hour GTT; if abnormal (≥ 135 mg/dL/7.5 mmol/L), then a fasting, 100-g, 3-hour GTT

The diagnosis is best based on results of an oral glucose tolerance test (OGTT—see table Glucose Thresholds for Gestational Diabetes Mellitus Using a 3-hour Oral Glucose Tolerance Test Glucose Thresholds for Gestational Diabetes Using a 3-hour Oral Glucose Tolerance Test* Glucose Thresholds for Gestational Diabetes Using a 3-hour Oral Glucose Tolerance Test* ). The OGTT may be done in 1 or 2 steps. Based on a recommendation from the 2013 National Institutes of Health (NIH) consensus development conference, screening begins with a 1-hour 50-g glucose load test (GLT); if results are positive (plasma glucose > 130 to 140 mg/dL [7.2 to 7.8 mmol/L]), a 3-hour 100-g OGTT is done.

Table

Optimal treatment of gestational diabetes Treatment Pregnancy makes glycemic control more difficult in preexisting type 1 (insulin-dependent) and type 2 (non–insulin-dependent) diabetes but does not appear to exacerbate diabetic retinopathy,... read more (with dietary modification, exercise, and close monitoring of blood glucose levels and insulin when necessary) reduces risk of adverse maternal, fetal, and neonatal outcomes. Women with gestational diabetes are at a higher lifetime risk of cardiovascular events and, after delivery, should be referred for appropriate cardiovascular risk assessment and follow-up.

Table

Women with gestational diabetes mellitus may have had undiagnosed diabetes mellitus before pregnancy. Thus, they should be screened for diabetes mellitus Screening Diabetes mellitus is impaired insulin secretion and variable degrees of peripheral insulin resistance leading to hyperglycemia. Early symptoms are related to hyperglycemia and include polydipsia... read more 6 to 12 weeks postpartum, using the same testing and criteria used for patients who are not pregnant.

Diabetes references

  • 1. Artal R: Exercise: The alternative therapeutic intervention for gestational diabetes. Clinical Obstetrics and Gynecology 46 (2):479–487, 2003.

  • 2. Artal R: The role of exercise in reducing the risks of gestational diabetes mellitus in obese women. Best Pract Res Clin Obstet Gynaecol 29 (1):123–4132, 2015.

Sexually Transmitted Infections (STIs)

Screening for sexually transmitted infections should be done during pregnancy to make treatment possible and to prevent adverse effects of intrauterine or perinatal transmitted infections to the fetus or neonate.

Routine prenatal care includes screening tests for HIV infection, hepatitis B, and syphilis and, if < 25 years, for chlamydial infection and gonorrhea at the first prenatal visit. Syphilis testing is repeated during pregnancy and at delivery if risk continues (1 STIs reference Risk factors for complications during pregnancy include Preexisting maternal disorders Physical and social characteristics (eg, age) Problems in previous pregnancies (eg, a previous history... read more STIs reference ). Pregnant women who have any of these infections are treated with antimicrobials.

Without treatment, risk of transmission of HIV Transmission Human immunodeficiency virus (HIV) infection results from 1 of 2 similar retroviruses (HIV-1 and HIV-2) that destroy CD4+ lymphocytes and impair cell-mediated immunity, increasing risk of certain... read more Transmission from woman to offspring is about 30% prepartum and about 25% intrapartum. Antiretroviral treatment of the pregnant woman before and during pregnancy and of the neonate within 6 to 12 hours of birth reduces risk of HIV transmission to the fetus Prevention Human immunodeficiency virus (HIV) infection is caused by the retrovirus HIV-1 (and less commonly by the related retrovirus HIV-2). Infection leads to progressive immunologic deterioration and... read more Prevention by two thirds; risk is probably lower (< 2%) with a combination of 2 or 3 antivirals. These drugs are recommended despite potential toxic effects in the fetus and woman.

Treatment of bacterial vaginosis, gonorrhea, or chlamydial infection may prolong the interval from rupture of the membranes to delivery and may improve fetal outcome by decreasing fetal inflammation.

STIs reference

Pyelonephritis

During pregnancy, recurrent bacteriuria occurs more frequently, and the incidence of pyelonephritis is higher. If bacteruria is present, 20 to 35 % of pregnant women develop a urinary tract infection (UTI), and pyelonephritis is possible.

Pyelonephritis is the most common nonobstetric cause of hospitalization during pregnancy.

Pregnant women with pyelonephritis are hospitalized for evaluation and treatment, primarily with urine culture plus sensitivities, IV antibiotics (eg, a 3rd-generation cephalosporin with or without an aminoglycoside), antipyretics, and hydration. Oral antibiotics specific to the causative organism are begun 24 to 48 hours after fever resolves and continued to complete the whole course of antibiotic therapy, usually 7 to 10 days.

Prophylactic antibiotics (eg, nitrofurantoin, trimethoprim/sulfamethoxazole) with periodic urine cultures are continued for the rest of the pregnancy.

Acute Surgical Problems

The most common reasons for intra-abdominal nonobstetric emergency surgery include appendicitis and biliary disorders. Prevalence is highest among women who are overweight, smoke, are older, or are multigravida and/or have had multiple gestations (1 Acute surgical problems reference Risk factors for complications during pregnancy include Preexisting maternal disorders Physical and social characteristics (eg, age) Problems in previous pregnancies (eg, a previous history... read more Acute surgical problems reference ).

Emergency and major surgery, particularly intra-abdominal, increases risk of the following:

However, surgery is usually tolerated well by pregnant women and the fetus when appropriate supportive care and anesthesia (maintaining blood pressure and oxygenation at normal levels) are provided, so physicians should not be reluctant to operate; delaying treatment of an abdominal emergency is far more dangerous.

After surgery, antibiotics and tocolytic drugs are given for 12 to 24 hours.

If nonemergency surgery is necessary during pregnancy, it is most safely done during the 2nd trimester.

Acute surgical problems reference

Genital Tract Abnormalities

Structural abnormalities of the uterus and cervix (eg, uterine septum, bicornuate uterus) make the following more likely:

Cervical insufficiency Cervical Insufficiency Cervical insufficiency (formerly called cervical incompetence) is painless cervical dilation resulting in 2nd-trimester pregnancy loss. Transvaginal cervical ultrasonography during the 2nd trimester... read more Cervical Insufficiency (incompetence) makes preterm delivery more likely. The risk of cervical insufficiency is higher in women who have had lacerations or injury of the cervix during a previous procedure (eg, therapeutic abortion, instrumental vaginal deliveries). Cervical insufficiency can be treated with surgical intervention (cerclage), vaginal progesterone, or sometimes a vaginal pessary.

If, before pregnancy, women have had a myomectomy in which the uterine cavity was entered, cesarean delivery is required because uterine rupture Uterine Rupture Uterine rupture is rupture of the myometrium in late pregnancy before labor or during labor, which usually occurs in patients with prior uterine surgery (eg, cesarean delivery or myomectomy)... read more is a risk during subsequent vaginal delivery.

Uterine abnormalities that lead to poor obstetric outcomes often require surgical correction, which is done after delivery.

Maternal Age

In women ≥ 35, the incidence of preeclampsia is increased, as is that of gestational diabetes Diabetes Mellitus in Pregnancy , dysfunctional labor Etiology , abruptio placentae Placental Abruption (Abruptio Placentae) Placental abruption (abruptio placentae) is premature separation of the placenta from the uterus, usually after 20 weeks gestation. It can be an obstetric emergency. Manifestations may include... read more , stillbirth Stillbirth Stillbirth is fetal death (fetal demise) at ≥ 20 weeks gestation (> 28 weeks in some definitions). Management is delivery and postpartum care. Maternal and fetal testing is done to determine... read more , and placenta previa Placenta Previa Placenta previa is implantation of the placenta over or near the internal os of the cervix. It typically manifests as painless vaginal bleeding after 20 weeks gestation; the source of bleeding... read more . These women are also more likely to have preexisting disorders (eg, chronic hypertension Hypertension Hypertension is sustained elevation of resting systolic blood pressure (≥ 130 mm Hg), diastolic blood pressure (≥ 80 mm Hg), or both. Hypertension with no known cause (primary; formerly, essential... read more Hypertension , diabetes Diabetes Mellitus (DM) Diabetes mellitus is impaired insulin secretion and variable degrees of peripheral insulin resistance leading to hyperglycemia. Early symptoms are related to hyperglycemia and include polydipsia... read more ). Because risk of fetal chromosomal abnormalities Overview of Chromosomal Abnormalities Chromosomal abnormalities cause various disorders. Abnormalities that affect autosomes (the 22 paired chromosomes that are alike in males and females) are more common than those that affect... read more increases as maternal age increases, genetic testing Preconception or Prenatal Carrier Testing of Parents Carrier testing is part of routine prenatal care and is ideally done before conception. The extent of carrier testing is related to how the woman and her partner weigh factors such as The probability... read more and detailed ultrasound screening for fetal malformations should be offered.

The most common chromosomal abnormality is autosomal trisomy. The US National Birth Defects Prevention Study (NBDPS) found that offspring of women > 40 years are at increased risk of cardiac abnormalities, esophageal atresia, hypospadias, and craniosynostosis (1 Maternal age reference Risk factors for complications during pregnancy include Preexisting maternal disorders Physical and social characteristics (eg, age) Problems in previous pregnancies (eg, a previous history... read more Maternal age reference ).

Maternal age reference

  • 1. Gill SK, Broussard C, Devine O, et al: Association between maternal age and birth defects of unknown etiology: United States, 1997-2007. Birth Defects Res A Clin Mol Teratol 94 (12):1010–1018, 2012. doi: 10.1002/bdra.23049 Epub 2012 Jul 23.

Maternal Weight

Pregnant women whose body mass index (BMI) was < 18.5 kg/m2 before pregnancy are considered underweight, which predisposes to low birth weight (< 2.5 kg) in neonates. Such women are encouraged to gain at least 12.5 kg during pregnancy.

Pregnant women whose BMI was 25 to 29.9 kg/m2 (overweight) or ≥ 30 kg/m2 (obese) before pregnancy are at risk of maternal hypertension Hypertension in Pregnancy Recommendations regarding classification, diagnosis, and management of hypertensive disorders (including preeclampsia) are available from the American College of Obstetricians and Gynecologists... read more and diabetes Diabetes Mellitus in Pregnancy Pregnancy makes glycemic control more difficult in preexisting type 1 (insulin-dependent) and type 2 (non–insulin-dependent) diabetes but does not appear to exacerbate diabetic retinopathy,... read more , postterm pregnancy Postterm Pregnancy Postterm pregnancy refers to gestation that lasts ≥ 42 (> 41 6/7) weeks. Late-term pregnancy is defined as 41 0/7 to 41 6/7 weeks. Antenatal surveillance should be considered at 41 weeks. Induction... read more , pregnancy loss Spontaneous Abortion Spontaneous abortion is pregnancy loss before 20 weeks gestation. Diagnosis is by pelvic examination, measurement of beta subunit of human chorionic gonadotropin, and ultrasonography. Treatment... read more , fetal macrosomia Large-for-Gestational-Age (LGA) Infant Infants whose weight is > the 90th percentile for gestational age are classified as large for gestational age. Macrosomia is birthweight > 4000 g in a term infant. The predominant cause is... read more , congenital malformations, intrauterine growth restriction Small-for-Gestational-Age (SGA) Infant Infants whose weight is < the 10th percentile for gestational age are classified as small for gestational age. Complications include perinatal asphyxia, meconium aspiration, polycythemia... read more , preeclampsia Preeclampsia and Eclampsia Preeclampsia is new-onset or worsening of existing hypertension with proteinuria after 20 weeks gestation. Eclampsia is unexplained generalized seizures in patients with preeclampsia. Diagnosis... read more , and the need for cesarean delivery Cesarean Delivery Cesarean delivery is surgical delivery by incision into the uterus. Up to 30% of deliveries in the US are cesarean. The rate of cesarean delivery fluctuates. It has recently increased, partly... read more . Ideally, weight loss should begin before pregnancy, first by trying lifestyle modifications (eg, increased physical activity, dietary changes). Women with overweight or obesity are encouraged to limit weight gain during pregnancy, ideally by modifying their lifestyle. The Institute of Medicine (IOM) uses the following guidelines:

  • Overweight: Weight gain limited to 6.8 to 11.3 kg (15 to 25 lb)

  • Obese: Weight gain limited to < 5 to 9 kg (11 to 20 lb)

However, not all experts agree with IOM recommendations. Many experts recommend an individualized approach that can include more limited weight gain plus lifestyle modifications (eg, increased physical activity, dietary changes), particularly for women with obesity (1 Maternal weight references Risk factors for complications during pregnancy include Preexisting maternal disorders Physical and social characteristics (eg, age) Problems in previous pregnancies (eg, a previous history... read more Maternal weight references ). During pregnancy, most women should be encouraged to exercise at least 3 times a week for a total of 150 minutes each week (2 Maternal weight references Risk factors for complications during pregnancy include Preexisting maternal disorders Physical and social characteristics (eg, age) Problems in previous pregnancies (eg, a previous history... read more Maternal weight references ).

For pregnant women with overweight or obesity, lifestyle modifications during pregnancy reduce the risk of gestational diabetes and preeclampsia.

Discussing appropriate weight gain, diet, and exercise at the initial visit and periodically throughout the pregnancy is important. The 2016 ACOG (American College of Obstetricians and Gynecologists) obesity toolkit is a helpful resource for managing overweight and obesity.

Maternal weight references

  • 1. Artal R, Lockwood CJ, Brown HL: Weight gain recommendations in pregnancy and the obesity epidemic. Obstet Gynecol 115 (1):152–155, 2010. doi: 10.1097/AOG.0b013e3181c51908

  • 2. Mottola MF, Davenport MH, Ruchat SM, et al: 2019 Canadian guideline for physical activity throughout pregnancy. Br J Sports Med 52 (21):1339–1346, 2018. doi: 10.1136/bjsports-2018-100056

Maternal Height

Exposure to Teratogens

Common teratogens (agents that cause fetal malformation) include infections, drugs, and physical agents. Malformations are most likely to result if exposure occurs between the 2nd and 8th week after conception (the 4th to 10th week after the last menstrual period), when organs are forming. Other adverse pregnancy outcomes are also more likely. Pregnant women exposed to teratogens are counseled about increased risks and referred for detailed ultrasound evaluation to detect malformations.

Common infections that may be teratogenic include

Commonly used drugs that may be teratogenic include

Hyperthermia or exposure to temperatures > 39° C (eg, in a sauna) during the 1st trimester has been associated with spina bifida.

Exposure to Mercury

Mercury in seafood can be toxic to the fetus. The FDA (see Advice about Eating Fish For Those Who Might Become or Are Pregnant or Breastfeeding and Children Ages 1–11 Years) recommends the following:

  • Avoiding tilefish from the Gulf of Mexico, shark, swordfish, big-eye tuna, marlin, orange roughy, and king mackerel

  • Limiting albacore tuna to 4 ounces (one average meal)/week

  • Before eating fish caught in local lakes, rivers, and coastal areas, checking local advisories about the safety of such fish and, if levels of mercury are not known to be low, limiting consumption to 4 ounces/week while avoiding other seafood that week

Tilefish from the Gulf of Mexico have the highest levels of mercury of all fish (as tested by the U.S. Food and Drug Administration (FDA); tilefish from the Atlantic Ocean can be safely eaten.

Experts recommend that women who are pregnant or breastfeeding eat 8 to 12 ounces (2 or 3 average meals)/week of a variety of seafood that is lower in mercury. Such seafood includes flounder, shrimp, canned light tuna, salmon, pollock, tilapia, cod, and catfish. Fish has nutrients that are important for fetal growth and development.

Prior Stillbirth

Stillbirth Stillbirth Stillbirth is fetal death (fetal demise) at ≥ 20 weeks gestation (> 28 weeks in some definitions). Management is delivery and postpartum care. Maternal and fetal testing is done to determine... read more is death of a fetus at ≥ 20 weeks gestation before or during delivery, as defined by the Centers for Disease Control and Prevention (CDC [ 1 Prior stillbirth references Risk factors for complications during pregnancy include Preexisting maternal disorders Physical and social characteristics (eg, age) Problems in previous pregnancies (eg, a previous history... read more Prior stillbirth references ]), or at > 28 weeks, as defined by the World Health Organization (2 Prior stillbirth references Risk factors for complications during pregnancy include Preexisting maternal disorders Physical and social characteristics (eg, age) Problems in previous pregnancies (eg, a previous history... read more Prior stillbirth references ). Fetal death during late pregnancy may have maternal, placental, or fetal anatomic or genetic causes (see table Common Causes of Stillbirth Common Causes of Stillbirth Common Causes of Stillbirth ). Having had a stillbirth or late abortion (ie, at 16 to 20 weeks) increases risk of fetal death in subsequent pregnancies. Degree of risk varies depending on the cause of a previous stillbirth. Fetal surveillance using antepartum testing (eg, nonstress testing, biophysical profile) is recommended.

Treatment of maternal disorders (eg, chronic hypertension, diabetes, infections) may lower risk of stillbirth in a current pregnancy.

Prior stillbirth references

Prior Preterm Delivery

Preterm delivery Preterm Labor Labor (contractions resulting in cervical change) that begins before 37 weeks gestation is considered preterm. Risk factors include prelabor rupture of membranes, uterine abnormalities, infection... read more is delivery before 37 weeks. Previous preterm delivery due to preterm labor increases risk of future preterm deliveries; if the previous preterm neonate weighed < 1.5 kg, risk of preterm delivery in the next pregnancy is 50%.

Women with prior preterm delivery due to preterm labor should be closely monitored at 2-week intervals after 20 weeks. Monitoring includes

  • Ultrasound evaluation, including measurement of cervical length, at 14 to 16 weeks

  • Testing for bacterial vaginosis

  • Measurement of fetal fibronectin

Women with a prior preterm birth due to preterm labor or with shortening ( 25 mm) of the cervix should be given intramuscular 17 alpha-hydroxyprogesterone.

Prior Neonate With a Genetic or Congenital Disorder

Risk of having a fetus with a chromosomal disorder Risk Factors for Genetic Disorders or Congenital Anomalies Prenatal genetic counseling is provided for all prospective parents, ideally before conception, to assess risk factors for genetic disorders. In addition, prenatal counseling provides information... read more is increased for most couples who have had a fetus or neonate with a chromosomal disorder (recognized or missed). Recurrence risk for most genetic disorders is unknown. Most congenital malformations are multifactorial; risk of having a subsequent fetus with malformations is 1%.

If couples have had a neonate with a genetic or chromosomal disorder, genetic screening Preconception or Prenatal Carrier Testing of Parents Carrier testing is part of routine prenatal care and is ideally done before conception. The extent of carrier testing is related to how the woman and her partner weigh factors such as The probability... read more is recommended. If couples have had a neonate with a congenital malformation, genetic screening, high-resolution ultrasonography, and evaluation by a maternal-fetal medicine specialist is recommended.

Polyhydramnios (Hydramnios) and Oligohydramnios

  • Uncontrolled maternal diabetes

  • Multifetal pregnancy

  • Isoimmunization

  • Fetal malformations (eg, esophageal atresia, anencephaly, spina bifida)

Oligohydramnios Oligohydramnios Oligohydramnios is amniotic fluid volume that is less than expected for gestational age; it is associated with maternal and fetal complications. Diagnosis is by ultrasonographic measurement... read more (deficient amniotic fluid) often accompanies congenital malformations of the fetal urinary tract and severe fetal growth restriction (< 3rd percentile). Also, Potter syndrome with pulmonary hypoplasia or fetal surface compression abnormalities may result, usually in the 2nd trimester, and cause fetal death.

Polyhydramnios or oligohydramnios is suspected if uterine size does not correspond to gestational date or may be discovered incidentally via ultrasonography, which is diagnostic.

In symptomatic patients (shortness of breath and/or abdominal discomfort), amniocentesis to remove excess amniotic fluid (amnioreduction) should be considered. Rarely, when maternal symptoms are severe, corticosteroids and preterm delivery should be considered. Amnioreduction relieves maternal symptoms, but amniotic fluid may reaccumulate rapidly and require repeat procedures. In patients with mild to moderate polyhydramnios, elective delivery at 39 weeks (or earlier, as indicated by symptoms) may be advisable; in making this decision, clinicians should also consider degree of cervical dilation and risk of premature rupture of membranes and umbilical cord prolapse.

Multifetal (Multiple) Pregnancy

Multifetal pregnancy reference

Prior Birth Injury

Most cerebral palsy Cerebral Palsy (CP) Cerebral palsy refers to a group of nonprogressive conditions characterized by impaired voluntary movement or posture and resulting from prenatal developmental malformations or perinatal or... read more and neurodevelopmental disorders are caused by factors unrelated to a birth injury. Injuries such as brachial plexus damage can result from procedures such as forceps or vacuum extractor delivery but often result from intrauterine forces during labor or malposition during the last weeks of pregnancy.

Previous shoulder dystocia Shoulder Dystocia Shoulder dystocia occurs during an attempted vaginal delivery (in the second stage of labor [pushing]) when the fetal head delivers but delivery does not progress because the anterior shoulder... read more is a risk factor for future dystocia, and the delivery records should be reviewed for potentially modifiable risk factors (eg, fetal macrosomia, operative vaginal delivery) that may have predisposed to the injury.

Drugs Mentioned In This Article

Drug Name Select Trade
Aluvea , BP-50% Urea , BP-K50, Carmol, CEM-Urea, Cerovel, DermacinRx Urea, Epimide-50, Gord Urea, Gordons Urea, Hydro 35 , Hydro 40, Kerafoam, Kerafoam 42, Keralac, Keralac Nailstik, Keratol, Keratol Plus, Kerol, Kerol AD, Kerol ZX, Latrix, Mectalyte, Nutraplus, RE Urea 40, RE Urea 50 , Rea Lo, Remeven, RE-U40, RYNODERM , U40, U-Kera, Ultra Mide 25, Ultralytic-2, Umecta, Umecta Nail Film, URALISS, Uramaxin , Uramaxin GT, Urea, Ureacin-10, Ureacin-20, Urealac , Ureaphil, Uredeb, URE-K , Uremez-40, Ure-Na, Uresol, Utopic, Vanamide, Xurea, X-VIATE
Anacin Adult Low Strength, Aspergum, Aspir-Low, Aspirtab , Aspir-Trin , Bayer Advanced Aspirin, Bayer Aspirin, Bayer Aspirin Extra Strength, Bayer Aspirin Plus, Bayer Aspirin Regimen, Bayer Children's Aspirin, Bayer Extra Strength, Bayer Extra Strength Plus, Bayer Genuine Aspirin, Bayer Low Dose Aspirin Regimen, Bayer Womens Aspirin , BeneHealth Aspirin, Bufferin, Bufferin Extra Strength, Bufferin Low Dose, DURLAZA, Easprin , Ecotrin, Ecotrin Low Strength, Genacote, Halfprin, MiniPrin, St. Joseph Adult Low Strength, St. Joseph Aspirin, VAZALORE, Zero Order Release Aspirin, ZORprin
Furadantin, Macrobid, Macrodantin, Urotoin
Primsol, Proloprim, TRIMPEX
Crinone, Endometrin , First - Progesterone MC 10, First - Progesterone MC 5, Prochieve, PROMETRIUM
GOPRELTO, NUMBRINO
Makena
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