Ch. 12 - High Risk Prenatal Care
what are the major causes of late pregnancy bleeding?
1. placenta previa 2. premature separation of the placenta / placental abruption
what are the risk factors for placenta previa?
1. previous c section (due to endometrial damage) 2. 35+ 3. multiparity 4. Hx suction curettage (due to endometrial damage) 5. smoking 6. living at higher altitudes 7. placenta previa in a previous pregnancy
what qualifies recurrent/habitual early miscarriage? -what would we begin to suspect?
3+ spontaneous pregnancy losses before 20 weeks -parental chromosomal abnormalities, antiphospholipid syndrome, uterine anomaly
what is a cause of late miscarriage?
cervical insufficiency
describe active management of placenta previa
If the woman definitely has placenta previa and is at or beyond 36 weeks gestation- we will pursue birth by C section (majority)
Typically, the cerclage is removed at 36 weeks gestation with an uncomplicated pregnancy; what situation would result in premature removal of the device?
1. pPROM 2. advanced preterm labor that puts pressure on the stitch
threatened miscarriage: management
1. bed rest (not proven to be effective) 2. repetitive vaginal ultrasounds and human chorionic gonadotropin + progesterone assessment to determine if fetus is still alive -if cervical dilation occurs = termination -symptoms resolve = continue expectant management
ectopic pregnancy: Clinical manifestations
1. Abdominal pain -begins as dull, lower quadrant pain on one side; progresses to sharp, stabbing pain on one side and then diffuse, constant sever pain generalized through the abdomen 2. Delayed menses -late by 1-2 weeks, lighter -mild/moderate dark red or brown intermittent vaginal bleeding 3. Abnormal vaginal bleeding
Placenta previa: management -what are the criteria for the 3 types of management?
1. Expectant management: fetus is < 37 wks with normal growth and no complications -Hospitalization: observation and bed rest 2. Active management: 36 weeks or beyond birth is appropriate. -C-section birth. 3. Home care: woman's condition is stable with absence of bleeding for 48 hours = discharged home *MONITOR BLOOD LOSS: HEMORRHAGE RISK even with firmly contracted fundus
how is placental abruption managed?
1. Expectant: fetus between 20-34 weeks and stable -close monitoring: abruption can happen at any time -fetal assessment for growth -regular NST or BPP -corticosteroids 2. Active: fetus is at term OR bleeding is moderate-severe and mom and baby are in jeopardy -IV access (large bore) -frequent vitals -serial labs -indwelling catheter -vaginal brith is preferred
what are the surgical options for ectopic pregnancy treatment?
1. Salpingectomy - removal of the entire tube. 2. Salpingostomy - an incision is made over the pregnancy site in the tube, and the products of coneption are gently and very carefully removed. The incision is not sutured, but left to close by secondary intention instead, given that this method results in less scarring.
what are the common bleeding disorders of early pregnancy?
1. miscarriage 2. cervical insufficiency 3. ectopic pregnancy 4. hydatidiform mole (molar pregnancy)
ectopic pregnancy
Fertilized ovum implanted outside uterine cavity -"tubal pregnancy"; 95% occur in uterine (fallopian) tube -Leading cause of infertility Other sites include: 1. Ovary 2. Abdominal cavity 3. Cervix
succenturiate placenta
when the placenta divides into 2+ lobes, rather than remaining as one single mass -risk for hemorrhage; fetal vessles run between the lobes ~vasa previa
when would an abdominal cerclage be placed?
Abdominal cerclage may be done at 11 to 13 weeks - done only if cervical cerclage unable to be placed. ONLY indication: failure of previous Hx-indicated transvaginal cerclage where spontaneous preterm birth occurred before 33 weeks
cervical insufficiency
Acquired or congenital; passive, painless dilation of the cervix -> to recurrent preterm births during the second trimester in absence of other causes -caused by structural weakness of cervical tissue (can be treated surgically)
inevitable miscarriage: management
Depends on symptoms 1. No pain, bleeding or infection = woman can pass fetus naturally if she wishes 2. ROM, pain, bleeding, infection = prompt termination via DC -prostaglandin meds: medical termination of pregnancy in 7-10 days
Hydatidiform mole (molar pregnancy): Diagnosis and Management
Diagnosis with Transvaginal ultrasound ("snow storm pattern" of diffuse intrauterine masses) and serum hCG levels (persistently high) Management: -Most pass spontaneously -Suction curettage is safe, rapid, and effective if necessary -Induction of labor with oxytocin or prostaglandins NOT recommended -> embolism
how is an abdominal cerclage placed?
Done by a laporotony. Suture is placed at the junction of the lower uterine segment and the cervix between 11 and 13 wks -C-section birth is necessary following an abdominal cerclage. -suture is left in place if future pregnancies are desired.
T or F: infections are a common cause of early miscarriage
FALSE! they are not a common cause
what are the classifications of placental abruption?
Grade 1 (mild)- 10-20% separation Grade 2 (moderate)- 20-50% separation Grade 3 (severe)- greater than 50% separation
describe expectant management of placenta previa
Hospitalization: observation and bed rest - 24/7 FHR monitoring -IV access -labs: obtain blood type - contact transfusion services for immediate cross match; hct, platelets, hgb, CBC -avoid vaginal exams and intercourse -Cesarean birth if bleeding does not stop
Hydatidiform mole (molar pregnancy): Clinical manifestations
In the beginning- no difference between a normal pregnancy 1. Vaginal bleeding - vaginal discharge may be dark brown (like prune juice) or bright red. 2. Significantly larger uterus
placenta previa complications: Maternal and fetal outcomes
Maternal: -*hemorrhage -development of abnormal placental attachment: placenta accreta syndrome Fetal -preterm birth -IUGR -fetal anomaly -anemia -malpresentation
placental abruption: Maternal, fetal, and neonatal outcomes
Maternal: hemorrhage - potential need for hysterectomy Fetal: -IUGR -oligohydramnios -preterm birth -hypoxemia -stillbirth Neonatal: vary on length of time without oxygen
disseminated intravascular coagulation (DIC)
Pathologic form of diffuse clotting causing widespread external and internal bleeding + clotting + ischemia -Triggered by severe preeclampsia, HELLP, and gram negative sepsis NEVER a primary diagnosis; the result of issue in clotting cascade -> widespread damage to vascular integrity
complete placenta previa
Placenta lies over the entire cervical os
when can a prophylactic cerclage versus rescue cerclage be placed?
Prophylactic cerclage is placed at 12 to 14 weeks of gestation rescue = 15 to 23 weeks
what is a major risk associated with vasa previa?
Rupture of membranes or traction on cord may tear one or more fetal vessels -> Fetus may rapidly bleed to death as a result *both variations of the disorder can result in this*
Placenta previa: diagnosis
Standard diagnosis is transabdominal ultrasound examination
when should placental abruption be highly suspected in a woman?
woman who experiences a sudden onset of intense, usually localized, uterine pain, with or without vaginal bleeding
hydatidiform mole / gestational trophoblastic disease
a benign tumor of the placenta consisting of multiple cystic and resembling a bunch of grapes; benign proliferative growth -Cause unknown - perhaps related to an ovular defect or a nutritional deficiency. -GTD: Abnormal fertilization without a viable fetus 1. complete 2. partial
Aside from fetal loss before 20 weeks gestation- what is a secondary diagnosis of abortion/ miscarriage?
a fetal weight less than 500 g
miscarriage / spontaneous abortion
a pregnancy that ends as a result of natural causes before 20 weeks of gestation 1. threatened 2. inevitable 3. incomplete 4. complete 5. missed 6. recurrent *all types of miscarriages can recur in future pregnancies; all aside from threatened can lead to infection
missed miscarriage
a pregnancy where the fetus has died but the products of conception are retained in utero for days-months; no bleeding or cramping -diagnosed when uterus stops increasing in size "early pregnancy loss"
septic miscarriage
a spontaneous miscarriage that is complicated by intrauterine infection; fever, uterine tenderness -culture + abort -broad spectrum antibiotics
The contributing cause to cervical insufficiency is cervical changes during pregnancy due to impaired cervical strength. The goal is to identify these women before conception or in early pregnancy so we can deter preterm birth- what complicates this goal?
assessment of cervical function to diagnose or rule out cervical insufficiency can only be done during pregnancy
what is an important intervention that is done after surgical evacuation of uterine contents?
administration of oxytocin to prevent hemorrhage -excessive bleeding = Methergine, carboprost may be given to contract uterus
Placenta previa: Clinical manifestations
bright red painless bleeding during the second or third trimester.
what are the symptoms of an incomplete miscarriage?
heavy-profuse bleeding with an open cervical os; tissue may be present with bleeding; severe uterine cramping -fetal expulsion with retained placenta
cervical insufficiency: treatment of choice -what is it? -when can it be done?
cervical cerclage: suture placement with McDonald technique - suture is placed around the cervix beneath the mucosa to constrict the internal os of the cervix. Removed at 36 weeks. can be placed prophylactically or as a therapeutic rescue procedure after cervical change has been identified
what are the symptoms of a complete miscarriage?
cervix has already closed after expulsion of fetal contents; slight bleeding and uterine cramping
T or F: all women with painless vaginal bleeding after 20 weeks gestation should be assumed to have placenta previa until proven otherwise
yup
what is an important consideration that women need to know when receiving methotrexate therapy?
don't use an analgesic stronger than acetaminophen; it can mask the SS of tubal rupture
what constitutes an early pregnancy loss? -What percent of pregnancies end in miscarriages? what percent are early? -SS
early = before 12 weeks Incidence and etiology 10-15% of all clinically recognized pregnancies end in miscarriage. The majority - greater than 80% of miscarriages are early pregnancy losses, occurring before 12 weeks gestation. SS: moderate discomfort and blood losss
Marginal placenta previa
edge of the placenta is seen on transvaginal ultrasound to be 2.5 cm or closer to the internal cervical os
Low-lying placenta previa
exact relationship of the placenta to the cervical os has not been determined OR apparent placenta previa in 2nd trimester
vasa previa
fetal vessels lie over the cervical os- they are implanted into the fetal membranes rather than into the placenta -risk for rupture or compression 1. velamentous insertion of the cord 2. Battledore / marginal insertion of the cord 3. succenturiate
T or F: women are less likely to have a successful pregnancy after an ectopic pregnancy
yup
what are the most important screening tools for ectopic pregnancy?
human chorionic gonadotropin and transvaginal ultrasound exam -progesterone > 25 ng/mL rules out ectopic pregnancy; < 5 = abnormal intrauterine pregnancy
Placenta previa
implantation of the placenta over the cervical opening or in the lower region of the uterus -> bleeding when the cervix dilates or effaces -Classification based on degree internal cervical os is covered by placenta 1. Complete placenta previa 2. Marginal placenta previa 3. Low-lying placenta previa
why would we measure fundal height in a woman with placental abruption?
increasing fundal height indicates concealed bleeding
abruptio placentae / placental abruption
premature separation of the placenta- detachment of part of all of a normally implanted placenta from the uterus after 20 weeks gestation -classified by type and severity
late miscarriage -what is it? -SS
loss of fetus between 12th and 20th week SS: severe pain similar to labor since the fetus must be expelled
what is the most consistent risk factor for placental abruption?
maternal HTN -concaine use
how is ectopic pregnancy treated?
methotrexate administration: antimetabolite and folic acid antagonist that destroys rapidly dividing cells -serious side effects even in low doses -prevents the need for surgery + safe and effective way to manage tubal pregnancy
what are the symptoms of an inevitable miscarriage?
moderate-heavy bleeding with an open cervical os; tissue may be present with bleeding; mild-severe uterine cramping -ROM and cervical dilation present = need to terminate -passing of conception products may occur
complete / classic hydatidiform mole
mole results from fertilization of egg with lost or inactivated nucleus; the nucleus of a sperm replicates itself
partial mole
result of two sperm fertilizing a normal ovum -> triploidy or quadraploidy genotypes
why are smoking and high altitudes risk factors for placenta previa?
smoking + high altitudes -> decreased uteroplacental oxygenation -> increased need for more placental surface
what are the symptoms of a threatened miscarriage?
spotting blood with closed cervix; mild uterine cramping
what is done if an ectopic pregnancy is detected in the abdominal cavity?
surgery to remove the embryo or fetus is usually performed as soon as an abdominal pregnancy is identified because of the high risk for hemorrhage at any time during the pregnancy.
what is the significance of a fetus living past 20 weeks of gestation?
the 20-week marker is considered to be the point of viability when a fetus may survive in an extrauterine environment
how does a complete trophoblastic pregnancy compare to normal?
the benign growth vesicle grows rapidly, causing the uterus to be larger than expected for the duration of pregnancy -complete mole has no fetus, no placenta -> hemorrhage into the uterine cavity and bleeding occur rather than birth :)
how is vasa previa diagnosed?
ultrasound using doppler imaging
what are the clinical manifestations of placental abruption?
vary with degree of separation -vaginal bleeding (can lead to hypovolemia) -abdominal pain: mild-severe and localized over one region of the uterus or diffuse over a rigid abdomen -uterine tenderness -contractions
velamentous cord insertion
vasa previa when the cord vessels begin to branch at the membranes and then course onto the placenta
How is methotrexate therapy evaluated for efficacy?
weekly hCG levels drawn - they should continue to drop steadily; complete resolution of ectopic pregnancy usually occurs in 2-3 weeks
T or F: with placenta previa, fundal height is often greater than expected for gestational age
yup since the placenta occupies the lower uterine segment, this elevates the fetus; due to abnormal placenta location, malpresentation is common (breech)
T or F: vital signs will reflect hypotension during a bleeding episode associated with placenta previa
~false vital signs may be normal. Even with heavy blood loss, a woman can lose 40% blood volume without showing signs of shock DECREASED OUTPUT is a better indicator of acute blood loss than vitals alone
