Fetal Development: Trimester 2
Abortion Methods: Trimester 2
Methods of Abortion Introduction
All medical abortion techniques induce
the uterus to contract and subsequently expulse the contents thereof.
Medical abortions preformed before 18 weeks gestation are considered more
dangerous and more expensive than surgical procedures.(6)
Therefore, determining fetal gestation age is then important and necessary
prior to the procedure. Menstrual history and physical examination are
usually adequate to estimate the gestational age, but for a more reliable
means of estimation, uterine ultrasonography is an option.(7)
Because the pregnancy and the fetus are more developed at this stage,
medical abortion is more complicated and risky than in the first trimester.
There are, however, a few options.
Administration of Hypertonic Solutions
The first method uses either saline or urea and is typically administered intra-amniotically.(5) This method has been associated with maternal complications, such as disseminated intravascular coalgulation (overstimulation of blood clotting mechanisms leading to spontaneous bleeding) (11) and therefore, in most cases, has been replaced by the administration of uterotonic drugs.
Uterotonic Drugs
These drugs are prostaglandins and cause
the smooth muscles of the uterus to contract. They can be in the form
of a suppository (such as Dinoprostone),(5)
taken orally (Misoprostol), or administered either intramuscularly or
intra-amniotically. A dosage of intravenous oxytocin is another alternative
method and is generally a safe choice, although when it is administered
in association with a saline abortion the risk of disseminated intravascular
coagulation increases.(5)
Whichever method is taken dilation of the cervix is necessary. There are
both synthetic dilators and and natural ones. Dilapan is a synthetic dilator
that ensures sterility and is easy to insert and remove. Laminaria is
dried seaweed that can dilate the cervix over some time (5)
(usually it needs to be inserted the night before the procedure.(4)
These procedures are relatively safe,
although the more advanced the gestation age the higher the risks are
for uterine perforation, infection, bleeding, amniotic fluid embolism,
and anesthetic reactions.
Regardless of which method, every patient who chooses a medical means
of abortion undergoes labor and delivery. This can be very emotionally
and physically traumatic (but can also be an outlet to allow a patient
to grieve).(4)