Second-trimester methods

SECOND-TRIMESTER METHODS
The more advanced the gestation, the higher the rate of complications.
Dilation and evacuation (D&E) (most common second-trimester abortion
procedure): Cervical dilation is performed by inserting osmotic laminaria
dilators 24 hours prior to the procedure. The cervical dilation in millimeters
equals the number of weeks of gestation (e.g., at 18 weeks, the cervix
should be dilated 18 mm).
Early second-trimester abortions (13–14 weeks) can be performed by
vacuum aspiration. After 14 weeks, the fetus is morcellated and removed in
pieces. Ultrasound guidance can ensure complete evacuation of pregnancy
tissues. A D&E is difficult to perform after 20 weeks due to toughness of
fetal tissues.
An intact D&E involves more advanced pregnancies, with ≥2 days of
laminaria treatment to obtain wide cervical dilation, allowing assisted
breech delivery of the fetus under ultrasound guidance and decompression
of the calvaria; the fetus is otherwise delivered intact (sometimes referred
to as “partial birth” abortion). An intact D&E can be performed up to 24
weeks.
Pain relief is achieved through local, intravenous, or spinal anesthesia.
Immediate complications may include uterine perforation, retained
tissue, hemorrhage, infection, and, rarely, disseminated intravascular
coagulation. Delayed complications may include cervical trauma with
resulting cervical insufficiency. Maternal mortality ratio is 4 per 100,000
women.
Labor induction methods: Stimulation of uterine contractions to dilate the
Table I-2-1. Methods of Induced Abortion
Trimester Method Procedure Maternity-Mortality
Ratio
First Trimester Surgical Suction dilation & curettage (D&C) 1
Medical Mifepristone (progesterone
antagonist)
1
Second
Trimester
Surgical Dilation & evacuation (D&E) 4
PGE1
Induction of labor contractions 8
Any Trimester Major
surgery
Hysterotomy, hysterectomy 25
cervix can be achieved with prostaglandins (intra-amniotic PGF2α
), vaginal
PGE2
(dinoprostone), IM 15-methyl PGF2α
(carboprost tromethamine), or
PGE1
(misoprostol). Interval from induction to delivery may be up to 24
hours.
Delivery of a live fetus may occur with use of prostaglandin (PG)
analogs; feticidal agents used include intracardiac injection of KCl or
digoxin.
Immediate complications include retained placentae (the most common
problem with all PG abortions), hemorrhage, and infection. Delayed
complications include cervical trauma with resulting cervical
insufficiency. Maternal mortality ratio is 8 per 100,000 women.