620
P A R T 7
Drugs acting on the reproductive system
■■
In women with functioning ovaries, fertility drugs
increase follicle development by stimulating FSH and
LH to increase the chances for pregnancy.
■■
Women receiving fertility drugs need to be monitored
for ovarian hyperstimulation, need to be aware of the
possibility of multiple births and need support and
encouragement to deal with the self-esteem issues
associated with infertility.
KEY POINTS
UTERINE MOTILITY DRUGS
Uterine motility drugs stimulate uterine contractions
to assist labour or induce termination. Salbutamol, a
beta
2
-selective adrenergic agonist, has been used as
a uterine motility agent to relax the gravid uterus to
prolong pregnancy. This drug is administered if uterine
contractions become strong before term to prevent
premature labour and delivery, which could result in
detrimental effects on the neonate, including death. Sal-
butamol is usually reserved for use after 20 weeks of
gestation, when the fetus has a chance of survival outside
of the uterus. If this drug is administered, the person
will need to be monitored for sympathetic stimulation
in the rest of the body (see Chapter 55, which deals with
drugs used to treat obstructive pulmonary diseases, for
a full discussion of salbutamol). However, nifedipine
(a calcium channel blocker) is now commonly preferred
in place of salbutamol. Prostaglandins are often used to
“ripen” the cervix to promote the onset of labour or ter-
mination of pregnancy. Oxytocics and prostaglandins
are discussed in detail in this section and in Table 40.3.
O
xytocics
Oxytocics
stimulate contraction of the uterus, much
like the action of the hypothalamic hormone oxytocin,
which is stored in the posterior pituitary. These drugs
TABLE 40.3
DRUGS IN FOCUS Uterine motility drugs
Drug name
Dosage/route
Usual indications
Oxytocics
carbetocin (Duratocin)
100 mcg by bolus IV injection over 1 minute
following birth of baby; given as single dose
only
Prevention and treatment of postpartum
uterine atony and excessive bleeding
following caesarean section under
epidural or spinal anaesthesia
ergometrine (generic)
0.2 mg IM, may repeat doses
Prevention and treatment of postpartum
and postabortion uterine atony;
management of third stage of labour
oxytocin (Syntocinon)
1–4 milliunits/min IV through an infusion
pump, increase as needed, do not exceed
20 milliunits/min; 10 units IM after delivery of
the placenta
Induction of labour; promotion of uterine
contractions postpartum; management of
third stage of labour
Prostaglandins
dinoprostone (Cervidil,
Propedil Gel,
Prostin E2)
20 mg vaginal pessary, may repeat q 3–5 hours
as needed
Vaginal gel: 1 mg intravaginally, additional
1–2 mg may be administered after 6 hours
to a maximum of 3 mg
A prostaglandin used for evacuation of the
uterus; stimulation of cervical ripening
before labour
gemeprost (Cervagem)
Pre-op 1 mg pessary into posterior vaginal
fornix. Termination one pessary q 3 hours to
maximum of five pessaries
Preoperative cervical softening, first or
second trimester pregnancy termination
misoprostol (GyMiso)
800 mg PO 36–48 hours following oral
mifepristone
Medical termination of pregnancy up to
49 days gestation
Evaluation
■
■
Monitor woman’s response to the drug (ovulation).
■
■
Monitor for adverse effects (abdominal bloating,
weight gain, ovarian hyperstimulation, multiple
births).
■
■
Evaluate the effectiveness of the teaching plan
(woman can name drug, dosage, adverse effects to
watch for and specific measures to avoid them).
■
■
Monitor effectiveness of comfort measures and
compliance with the regimen.
