Medical Archive

Introduction

S11 P42 https://hsnowhome.wpcomstaging.com/2020/04/13/c42-preterm-birth/

Nomenclature

First-trimester spontaneous abortion

Pathogenesis

?? ??? ??? MPS ??? lost. ? 70%? ?? loss

Causes

• M/c: chromosomal anomalies (especially trisomy 16)
• Hypercoagulable states (e.g., antiphospholipid syndrome)
• Congenital infection
• Exposure to teratogens (especially during the first 2 weeks of embryogenesis).
  • First two weeks of gestation: spontaneous abortion
  • Weeks 3-8: risk of organ malformation
  • Months 3-9: risk of organ hypoplasia
  • C12 Teratology, Teratogens, and Fetotoxic Agents

Incidence

Fetal factors

Blighted ovum (????)
???? – trisomy (m/c)
???? – euploid (m/c)

• Infection
• Medical disorders
• Cancer
• Surgical procedures
• Nutrition
• Social and behavioral factors
• Occupational and environmental factors

Maternal factors

IIOC
*Aneuploid
Trisomy>Turner>Triploidy

Paternal factors

Spontaneous abortion clinical classification

	Definition	Os	Symptom	Diagnosis	Treatment	RhoGAM
Threatened	Vaginal bleeding <20?	Closed	Pain	US ?-hCG	Conservative (???+bed rest)	12? ????
Inevitable	No tissue <20?	Opened	Pain	US ?-hCG	Suction curettage	??
Incomplete	Partial expulsion >10?	Opened	+bradycardia	US ?-hCG	Suction curettage	??
Complete	Total expulsion	Closed
Missed	Demise <20?	Closed		US ?-hCG	Natural expulsion PGE1 or D&C	??

Threatened abortion

• Management
  • Expectant
  • Outpatient observation
    • Serial ultrasound until the symptoms resolve or there is progression to a complete abortion.
  • Bed rest and hospitalization
    • Do not improve outcomes and are not recommended.
  • Suction curettage
    • Indicated when patients are anemic, hemodynamically unstable, or septic.

Incomplete abortion

Complete abortion

Missed abortion ?? ??

Inevitable abortion

• Definition
  • Threatened abortion?? ??? ??? 6?? ?? ??, ?? ?? (>1.5cm), membrane? ??, cramping severe pain ??

Septic abortion

• Risk factors
  • Retained POC from:
    • Elective abortion with nonsterile technique
    • Missed or incomplete abortion (rare)
• Clinical presentation
  • Fever, chills, abdominal pain
  • Sanguinopurulent vaginal discharge
  • Boggy, tender uterus; dilated cervix
  • Pelvic ultrasound: retained POC, thick endometrial stripe
• Management
  • IV fluids
  • Broad-spectrum antibiotics
  • Suction curettage

Anti-D immunoglobulin

Recurrent miscarriage

• 3? ?? loss
• 2? ?? loss and…
  • Older>35yr
  • Heart beat? ?? loss
  • ??? ? ?? ?

Etiology

Work up
???? ??, HSG, ????, ????

Parental chromosomal abnormalities

??? 2-5%

• Genetic (2-5%)
  • Balanced translocation -m/c
  • FHx? ??? Term birth ???? r/o

Anatomical factors

??? 10-15% – 1/4? fertility? obstetric problem

• Didelphus
  • ??? 2????? ??? ??
  • Laparo : ??, HSG: ?? ?
• Bicornuate
  • ???? ? ??? ??
  • Laparo: ??, MRI: ?? ??
• Septate
  • ???? ?? ?? ?? ?
  • Laparo: ??, HSG: ?? ??
• Mayer-Rokitansky SD
  • Vaginal, uterine agenesis
  • ‘?? ??’??? ???? ?? X
  • ??: vaginal palpation, hysterosalphingography(HSG)
  • ??: No surgical procedure, septum? resection / Didelphys; Strassmans operation? ? ??

Immunological factors

Endocrine factors

Midtrimester abortion

Incidence and etiology

Management

Cervical insufficiency

‘Incompetent internal Os of cervix (IIOC)’

• Definition: painless cervical dilation, in the absence of uterine contractions and/or labor, in the second trimester of pregnancy
• Etiology: Most cases are idiopathic.
• Risk factors
  • Previous mid-trimester pregnancy loss and/or preterm birth
  • Previous obstetric or gynecological trauma (e.g., termination of pregnancy, rapid delivery, multiple gestations, or cervical conization)
  • Cervical connective tissue weakness (e.g., Ehler-Danlos syndrome)
  • Diethylstilbestrol exposure
  • Collagen defects, uterine abnormalities
• Clinical features
  • Painless cervical dilation with or without prolapsed membranes
  • Nonspecific findings 
    • Pelvic cramps or backache 
    • ? Volume, changed color (yellow or blood-stained), and/or thinner consistency of vaginal discharge
• Diagnosis
  • Clinical diagnosis typically before 24 weeks’ (may be up to 28 weeks’) gestation
  • OR history of ? 2 previous mid-trimester pregnancy losses or ? 3 preterm births not explained by any other cause, and a transvaginal ultrasound cervical length < 25 mm before 24 weeks’ gestation

Surgical indications

Hx / IIOC / short cervix / rescue (emergency)

Presurgical preparation

Progesterone supplementation (vaginal or intramuscular): indicated for a short cervical length at < 24 weeks’ gestation in the absence of a previous preterm birth

Vaginal cerclage

• Performed in the first trimester (ie, 12-14 weeks gestation)
• A suture is placed to reinforce and add tensile strength to the cervix
• Removed at term to allow vaginal delivery

• Definition: placement of a supportive suture in the cervicovaginal junction to prevent early pregnancy loss or preterm birth
• Methods: McDonald cerclage , Shirodkar cerclage 
• Timing: < 24 weeks gestation; most commonly performed at 13–16 weeks gestation 
• Indications: only in singleton pregnancies 
  • Multiple previous preterm births or pregnancy losses in the second trimester
  • A previous preterm birth and current ultrasound diagnosis of a shortened cervix (cervix length <25 mm) at <24 weeks gestation 
  • Cervical dilation on inspection at <24 weeks gestation
  • Prior cerclage due to cervical insufficiency at <24 weeks gestation
• Contraindications
  • Preterm labor
  • Premature rupture of membranes
  • Chorioamnionitis or vaginal infection
  • ? 24 weeks’ gestation
  • Unexplained vaginal bleeding
  • Multiple gestations

Transabdominal cerclage

Complications

Induced abortion

1st trimester ??? ??? ?
(Uterine perforation, laceration)
Perforation ??? open/laparo ??

Classification

Abortion in the United States

Legal influence

?? ??

1. ??? ??
2. ??, ??? ? ?? ??? ??
3. ?? ??? ??? ?. ??? 6?? ??? delivery??.

Provider avilability

First-trimester abortion methods

Surgical abortion

Suction curettage is indicated fore hemodynamically unstable patients with anemia from acute blood loss.

Medical abortion

Mifepristone, misoprostol

Second-trimester abortion methods

• 20-23 weeks
  • D&E or vaginal delivery
• ?24 weeks
  • Vaginal delivery is the preferred.

Delation and evacuation

Medical abortion

Fetal and placental evaluation

Consequences of elective abortion

Postabortal contraception