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If hyperprolactinemia is evident, any secondary causes such as

medications are investigated. Certain antipsychotics, antihypertensives, or

antidepressants can increase prolactin levels and should be discontinued and

replaced with agents that do not increase prolactin. If the underlying cause cannot be

addressed, a dopamine agonist may restore testicular function and sperm

production.

12

T.R.’s husband’s medical history does not support an identifiable cause of altered

sperm production or function. He does not report any signs of sexual dysfunction or

take medications that may negatively affect libido or erectile or ejaculatory function.

All components of the semen analysis are above the lower limit defined by the World

Health Organization. His normal physical examination and medical history also

support a lack of identifiable male causes of infertility. In this case, the extensive

testing of both T.R. and her husband has revealed no obvious contributor to

infertility.

TREATMENT APPROACHES

CASE 48-1, QUESTION 7: The couple completes their evaluation and is diagnosed with unexplained

infertility. What is the initial approach to treatment?

p. 957

p. 958

The diagnosis of unexplained infertility, or no identifiable cause after evaluation,

accounts for up to 25% of cases.

19 The treatment approach is empiric but typically

incorporates medications to stimulate ovulation, often in conjunction with intrauterine

insemination or other infertility procedures, which are discussed later in the chapter.

Regardless of the treatment approach, all couples pursuing pregnancy are

encouraged to avoid tobacco, alcohol, and illicit substances, and limit caffeine

intake.

9 The female partner should take a daily supplement containing 400 to 800 mcg

of folic acid to reduce the risk of neural tube defects once pregnancy occurs.

20 Any

chronic medications must be evaluated for potential safety issues during pregnancy

and discontinued or switched to a safer alternative. Patients are encouraged to

achieve and maintain a normal weight.

9 Recommendations pertinent to T.R. include

discontinuation of alcohol use, limited caffeine intake, and initiation of a daily

multivitamin with 400 to 800 mcg of folic acid. T.R. should also confirm plans for

monitoring her asthma symptoms during pregnancy. Albuterol use during pregnancy

will be continued, but the frequency of use will be monitored carefully.

21

Ovarian Stimulation

There are two general treatment approaches to ovarian stimulation: “ovulation

induction” (OI) and “superovulation (SO).” The approach depends on a patient’s

underlying ovulatory function. Ovulation induction is utilized in patients who are not

ovulating to promote an ovulatory cycle. This method may be accompanied by timed

natural intercourse or the use of insemination procedures to achieve pregnancy.

Superovulation, or controlled ovarian stimulation (COS), incorporates many of the

same medications, but is appropriate for women who are already having ovulatory

cycles but are still experiencing infertility. Additionally, SO is appropriate for

infertility procedures where the development of multiple ovarian follicles is

desirable (Case 48-2). The general approach to medication use with both strategies

is described subsequently.

Anovulatory women with adequate ovarian reserve and no other treatable cause

are candidates for OI. This process is designed to mimic the hormonal patterns of the

normal menstrual cycle. Follicle-stimulating hormone guides the initial recruitment

and development of ovarian follicles early in the menstrual cycle. This is followed

by development of a dominant follicle and increased estradiol levels. The elevated

estrogen triggers the LH surge and the release of the ovum mid-cycle for fertilization

(Fig. 48-1). The goal of OI is the development of a single dominant follicle.

22

The choice of medications for OI is dictated by hypothalamic–pituitary–ovarian

function. With adequate hypothalamic function, an oral regimen of CC, which exhibits

estrogen agonist and antagonist activity, is often utilized first line. Clomiphene citrate

inhibits estrogen binding in the hypothalamus to stimulate release of GnRH and

pituitary gonadotropins and induce ovarian follicular development. Ovulation is

successful in approximately 75% of patients using CC.

19 Oral aromatase inhibitors

are not approved by the US Food and Drug Administration (FDA) for OI, but also

increase release of GnRH and pituitary gonadotropins through an estrogen antagonist

effect.

19

If hypothalamic or pituitary dysfunction is detected or if oral regimens are not

successful, injectable gonadotropins are administered. The most common

gonadotropin regimens use FSH administered alone or in combination with LH,

depending on whether the patient has hypogonadotropic or eugonadotropic

hypogonadism (Table 48-3).

23

Injections are initiated at low daily doses until a

dominant follicle has matured. Ovulation is then triggered with an injection of human

chorionic gonadotropin (hCG) to simulate the LH surge that naturally occurs midcycle. This is timed with natural intercourse or other infertility procedures to achieve

pregnancy.

24

Table 48-3

Gonadotropins for Ovulation Induction/Superovulation

Ingredient Product Name Strength/Dosage Form

Route of

Administration

hMG (menotropins) Menopur Powder for reconstitution: 75 IU FSH

activity and 75 IU LH activity/vial

SC

Urinary FSH

(urofollitropin)

Bravelle Powder for reconstitution: 75 IU FSH

activity/vial

IM or SC

Recombinant FSH

(follitropin alfa)

Gonal-f multi-dose Powder for reconstitution: 450 or

1,050 IU FSH activity/vial

SC

Gonal-f RFF 75 IU Powder for reconstitution: 75 IU FSH

activity/vial

SC

Gonal-f RFF

Rediject

Solution: 300, 450, or 900 IU FSH/pen SC

Recombinant FSH

(follitropin beta)

Follistim AQ Vial Solution: 75 IU FSH/0.5-mL vial IM or SC

Follistim AQ

cartridge for

Follistim Pen

Solution:300, 600, or 900 IU

FSH/cartridge

SC

Urinary hCG Chorionic

gonadotropin

(generic)

Powder for reconstitution: 10,000 IU

LH activity/vial

IM

Pregnyl Powder for reconstitution: 10,000 IU

LH activity/vial

IM

Novarel Powder for reconstitution: 10,000 IU

LH activity/vial

IM

Recombinant chorionic

gonadotropin alfa

Ovidrel Prefilled syringe: 250-mcg r-hCG/0.5

mL

SC

FSH, follicle-stimulating hormone; hCG, human chorionic gonadotropin; hMG, human menopausal gonadotropin;

IM, intramuscular; LH, luteinizing hormone; r-hCG, recombinant human chorionic gonadotropin; SC, subcutaneous.

Source: Facts & Comparisons eAnswers.

https://fco.factsandcomparisons.com/lco/action/doc/retrieve/docid/fc_dfc/5548530;

https://fco.factsandcomparisons.com/lco/action/doc/retrieve/docid/1081/5546104;

https://fco.factsandcomparisons.com/lco/action/doc/retrieve/docid/fc_dfc/5548528;

https://fco.factsandcomparisons.com/lco/action/doc/retrieve/docid/fc_dfc/5548529;

https://fco.factsandcomparisons.com/lco/action/search?q=pregnyl&t=name;

https://fco.factsandcomparisons.com/lco/action/search?q=ovidrel&t=name. Accessed June 14, 2017.

p. 958

p. 959

The oral and injectable medications used for OI are also incorporated into

regimens for SO. They are administered in doses and schedules intended to develop

multiple ovarian follicles, rather than one dominant follicle. This results in a greater

number of oocytes available for fertilization. Because T.R. has ovulatory cycles, but

has unexplained infertility, SO is the treatment approach considered most

appropriate.

CASE 48-1, QUESTION 8: What medication regimen is recommended for T.R.’s unexplained infertility?

There are multiple methods for ovulation stimulation that utilize oral or injectable

medications. Clomiphene citrate is the most common initial choice because of the

convenience and low cost of an oral regimen and the widespread experience with its

use.

CLOMIPHENE CITRATE

The competitive binding of CC to estrogen receptors in the hypothalamus stimulates

release of GnRH. This promotes gonadotropin release from the anterior pituitary,

leading to follicular development, increased estradiol production, and ovulation. As

previously described, the mechanism of action of CC requires an intact

hypothalamic–pituitary–ovarian axis.

25 The typical initial dosing regimen for CC is

50 mg once daily for 5 days starting between days 2 through 5 of the menstrual cycle.

Ovulation usually occurs 5 to 12 days after the fifth dose is taken. If ovulation is

documented but pregnancy does not occur, the same dose of CC is used in future

cycles. If ovulation does not occur, then the dose is increased by 50 mg with each

subsequent cycle. Although the product labeling does not recommend doses above

100 mg/day, CC doses as high as 250 mg have been described in the literature.

25

Superovulation for unexplained infertility with CC is recommended in combination

with intrauterine insemination (IUI), because this improves pregnancy and live birth

rates over CC alone or no intervention.

25

Intrauterine insemination introduces a

processed semen sample directly to the uterus via a catheter placed through the

cervix. The procedure is timed with ovulation to maximize sperm exposure for

fertilization. This is accomplished by using a urinary ovulation home test kit to

identify the natural LH surge or injecting hCG to trigger ovulation and planning the

IUI 24 to 36 hours later. Due to the nature of the procedure, patients with bilateral

obstruction of the fallopian tubes are not candidates for IUI.

26

T.R.’s evaluation shows no evidence of hypothalamic or pituitary dysfunction, so

she is an appropriate candidate for CC. Once her next cycle begins, she should

initiate a 5-day regimen of CC 50 mg once daily starting on the fifth day of menstrual

bleeding, with plans for an IUI following documentation of ovulation.

CASE 48-1, QUESTION 9: T.R. begins a regimen of CC and experiences hot flashes and nausea, but

chooses to complete the 5-day course. What is the likely cause of her symptoms?

Vasomotor symptoms are a common complaint during a short treatment course of

CC, occurring in approximately 10% of users. Additional side effects include

headache, breast tenderness, irritability, mood swings, and nausea. Although visual

disturbances are reported in less than 2% of patients, symptoms such as blurred

vision or light sensitivity should be reported and evaluated to prevent serious

complications.

19,25 All medications for SO can result in multiple gestation

pregnancies. Clomiphene citrate for unexplained infertility is associated with

multiple gestation in approximately 3% to 7% of pregnancies, primarily resulting in

twins.

25 Early concerns about increased rates of ovarian cancer in women exposed to

more than 12 cycles of CC have been minimized based on recent data.

25

In this case, T.R. is experiencing side effects commonly associated with CC. They

are not treatment limiting, and she is not reporting a change in vision that would

require further evaluation. She can safely proceed with treatment by monitoring for

an LH surge using a home ovulation test kit and undergoing IUI.

CASE 48-1, QUESTION 10: The pregnancy test after the first cycle of CC and IUI is negative. What other

options are available for this couple?

Multiple treatment cycles with the combination of CC and IUI are commonly

pursued, but there is little evidence for effectiveness beyond six attempts.

25

In some

cases, alternatives to CC for SO may be desirable because of poor tolerability or

treatment failure. Aromatase inhibitors or gonadotropins are suitable alternatives to

combine with IUI.

AROMATASE INHIBITORS

The aromatase inhibitors letrozole and anastrozole are oral alternatives to CC,

although they are not FDA-labeled for OI or SO. Aromatase is an enzyme that

converts androstenedione to estrone and testosterone to estradiol. Aromatase

inhibitors reduce systemic estrogen levels by blocking this conversion in the ovary,

resulting in increased gonadotropin secretion and follicular development. The higher

concentration of androgens that remains in the ovary increases follicular sensitivity to

FSH and further facilitates development.

27

The recommended administration schedule is similar to clomiphene: once daily for

5 days beginning on cycle days 3 to 5. Although daily doses of letrozole 2.5 or 5 mg

or anastrozole 1 mg have been studied for this purpose, there is more evidence

available for letrozole. Pregnancy rates with letrozole appear to be similar to that of

CC.

28 Adverse effects experienced with aromatase inhibitors resemble those of CC

and include vasomotor symptoms, nausea, and fatigue. The aromatase inhibitors do

not affect cervical mucus or endometrial development, but this finding has not

translated into improved pregnancy outcomes in clinical studies. Development of

fewer follicles may result in a lower risk of multiple gestation pregnancy compared

with CC. Initial concerns of the teratogenic potential of aromatase inhibition during

fetal development prompted a warning against use in premenopausal women who are

or may become pregnant.

27 However, surveillance studies do not demonstrate higher

rates of congenital malformations with letrozole as compared to CC.

27,29 The early

timing of administration in the cycle reduces the risk of fetal exposure. Continued

monitoring of pregnancy outcomes is needed to confirm safety.

GONADOTROPINS

If oral agents are unsuccessful, SO can be attempted with injectable gonadotropins

including FSH alone or in combination with LH (Table 48-3).

23 A standard protocol

involves daily injections of FSH or a combination of FSH and LH to stimulate

follicular development. Human chorionic gonadotropin is commonly administered as

a single injection to finalize follicular development and induce ovulation.

19 Dosing

recommendations, key differences between formulations, and risks associated with

gonadotropin use are reviewed in more detail in Case 48-2.

T.R.’s complaints of vasomotor symptoms are well documented with CC.

Although the aromatase inhibitors are another oral option, the likelihood of hot

flashes is similar. However, if the couple continues to be unsuccessful with future

cycles of CC plus IUI, letrozole can serve as an alternative prior to use of injectable

gonadotropins. In vitro fertilization (IVF) is commonly reserved until after multiple

IUI procedures are attempted and unsuccessful.

p. 959

p. 960

Table 48-4

Description of Select Infertility Procedures

Classification Procedure Description

Insemination Intrauterine, intracervical, intravaginal Delivery of a prepared semen sample to the

intended site (vagina, cervix, uterus) during

ovulation

Assisted

reproductive

technology

Assisted hatching Mechanical or chemicalseparation of the

blastocyst from the zona pellucida (membrane

surrounding the oocyte) during embryonic

development in vitro

Embryo cryopreservation Freezing and storage of embryos for future ART

cycles

Gamete intrafallopian transfer Laparoscopic transfer of the unfertilized oocytes

and sperm to the fallopian tube for fertilization

In vitro fertilization—embryo transfer Transfer of one or more embryos resulting from

in vitro fertilization into the uterus through the

cervix

Intracytoplasmic sperm injection In vitro injection of the sperm into the oocyte

Preimplantation genetic

diagnosis/screening

Examination of oocytes, zygotes, or embryos for

specific genetic conditions (diagnosis) or for

general genetic alterations (screening)

Zygote intrafallopian transfer Laparoscopic transfer of the fertilized oocyte

(zygote) into the fallopian tube

ART, assisted reproductive technology.

Source: Zegers-Hochschild F et al. The International Committee for Monitoring Assisted Reproductive Technology

(ICMART) and the World Health Organization (WHO) revised glossary on ART terminology, 2009. Hum Reprod.

2009;24:2683.

Assisted Reproductive Technology

OVERVIEW AND INDICATIONS

There are a variety of procedures to address infertility factors specific to each

couple. Insemination processes (intrauterine, intracervical, and intravaginal) are

categorized separately from those using assisted reproductive technology (ART), or

the manipulation of oocytes and embryos (Table 48-4).

30 The Centers for Disease

Control and Prevention monitors ART in the United States through the National ART

Surveillance System. The use of ART is trending upward, with the number of cycles

increasing from just over 122,000 in 2003 to more than 157,000 in 2012.

31

The primary ART is IVF, which involves retrieval of oocytes after SO,

fertilization in vitro, and transfer of the embryo(s) directly to the uterus through the

cervix, bypassing the fallopian tubes (Fig. 48-2; Table 48-4).

31

Intracytoplasmic

sperm injection (ICSI), or the injection of sperm directly into the oocyte during the

fertilization process, accompanies IVF if severe sperm dysfunction is evident. A

variety of ancillary procedures can be used based upon each couple’s history and

clinical presentation. These include genetic screening and cryopreservation of

embryos. Assisted reproductive technology also allows couples to use donor sperm

and/or oocytes to overcome severe sperm or ovarian dysfunction that cannot be

addressed through other methods. The option of using donor oocytes uniquely targets

infertility due to diminished ovarian reserve.

Figure 48-2 In vitro fertilization process.

p. 960

p. 961

CASE 48-2

QUESTION 1: F.J., a 39-year-old woman, and her 42-year-old husband are a recently married couple

undergoing a comprehensive infertility evaluation after 6 months without conceiving. F.J.’s medical history is

positive for seasonal allergic rhinitis, dysmenorrhea, and a history of chlamydia at age 21. Her current screen

for sexually transmitted infections is negative. F.J.’s reproductive history reveals menarche at age 11, no prior

pregnancies, and regular menstrual cycles approximately 30 days in length. Her body mass index is 21 kg/m

2

.

There are no abnormal findings on her physical examination. She undergoes a CC challenge test and her FSH

and estradiol levels on cycle day 3 are 7 mIU/mL and 46 pg/mL, respectively. The day 10 FSH is 6 mIU/mL.

Her HSG shows complete occlusion of the left fallopian tube and partial occlusion of the right fallopian tube.

What findings support female factor infertility?

This couple is undergoing evaluation of infertility after only 6 months without

conceiving because of F.J.’s advanced age (older than 35) and history of chlamydia,

which places her at increased risk of complications from pelvic inflammatory

disease. The occlusion of her fallopian tubes is most likely from the chlamydial

infection at age 21, which may or may not have been detected and treated at that time.

Laparoscopy would be necessary to rule out any additional causes such as

endometriosis. Further hysteroscopic procedures are warranted to define the location

and type of obstruction and to determine whether surgical repair is feasible.

32 Her

regular menstrual cycle length and history of dysmenorrhea is supportive of an

ovulatory menstrual cycle and her CC challenge test shows adequate ovarian reserve,

with normal levels of FSH and estradiol. She is within the normal weight range and

has normal findings upon physical examination. However, further laboratory testing

may be warranted to confirm normal thyroid and pituitary function and rule out

findings associated with PCOS.

CASE 48-2, QUESTION 2: F.J.’s husband has normal findings upon physical examination. His semen

analysis yields the following results:

Semen volume, 3 mL

Sperm number, 41 × 10

6

Sperm concentration, 18 × 10

6

/mL

Sperm total motility, 35%

Sperm progressive motility, 30%

Sperm vitality, 60%

Sperm morphology, 2%

A repeat analysis produces similar results. Additional laboratory findings include:

Testosterone, 650 ng/dL

FSH, 4 mIU/mL

Prolactin, 14.2 ng/mL

What is the significance of these findings for male factor infertility and the choice of ART for this couple?

The semen analysis is significant for sperm motility and morphology values below

the lower reference limit defined by the World Health Organization. The semen

volume, sperm number, and vitality measurements are just above the lower reference

limit (Table 48-2).

18

Interventions to improve sperm parameters typically target the

underlying cause if possible, such as treatment of hyperprolactinemia or

supplementation with testosterone. In some cases, sperm production can be

stimulated through the use of medications that influence the hypothalamic–pituitary–

testicular axis. For example, CC may improve sperm concentrations in men with

hypogonadotropic hypogonadism by stimulating hypothalamic release of GnRH.

There is no consensus regarding the optimal dosage regimen, which is FDA-labeled

for use in women only. Small clinical studies have examined CC in initial daily

doses of 12.5 to 25 mg, in addition to alternate-day and cyclic dosing for treatment

periods of several months with positive results.

33 Administration of various regimens

of injectable gonadotropins (FSH, LH, or hCG) also improves pregnancy rates.

33

Given this patient’s normal serum testosterone and FSH, CC or gonadotropins are not

recommended therapies. His prolactin is normal as well, ruling out this potential

secondary cause. In this case, there is no identifiable cause of the abnormal

parameters so it is deemed idiopathic, without a known etiology.

Antioxidants such as vitamin C, vitamin E, folic acid, zinc, selenium, and Lcarnitine are reported to counteract negative effects from oxidative stress on sperm.

Some small studies have demonstrated improvement in sperm motility, concentration,

and morphology. A systematic review documented a possible increase in live birth

rates with the use of antioxidants.

34 F.J.’s husband may choose to take a daily

antioxidant supplement as they move forward with other treatment modalities.

Insemination procedures are one approach to address abnormal findings on semen

analysis. Bypassing the cervix and placing the sperm closer to the fallopian tubes

near the time of ovulation can overcome lower sperm counts and motility issues. In

regard to this couple, however, F.J. does not have patent fallopian tubes and would

not be a candidate for IUI. An ART procedure will be necessary to address both

female and male infertility factors.

IVF is more appropriate than gamete intrafallopian transfer and zygote

intrafallopian transfer due to F.J.’s tubal findings. Although surgical repair of the

obstructed fallopian tubes may be possible in some cases, many couples choose to

bypass this option and pursue ART, especially when there are additional male

factors.

32 F.J. will need a surgical evaluation to confirm whether this is

recommended prior to proceeding to ART. F.J. is ovulatory with adequate ovarian

reserve, so the use of donor oocytes is not required. Her husband’s abnormal sperm

parameters can be addressed through ICSI, with the option of using donor sperm in

the future, if necessary.

IN VITRO FERTILIZATION

The basic steps in an IVF protocol include SO/COS, oocyte retrieval, fertilization,

embryo culture, and embryo transfer. Medications are primarily used during three

main stages of IVF: COS, oocyte retrieval, and luteal phase support (Table 48-5).

(For a step-by-step guide to all the steps in this complex process, go to

http://www.sart.org/patients/a-patients-guide-to-assisted-reproductivetechnology/general-information/art-step-by-step-guide/) Treatment protocols

vary widely in the medications used, dosing regimens, and timing of administration.

A sample in vitro fertilization protocol representing F.J.’s experience is provided in

Figure 48-3.

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