A. Definitions and Characteristics

1. Infertility diagnosis usually made when conception has not occurred within 1 year of unprotected sexual exposure in a couple
2. Sterility usually requires infertility and no effective therapy
3. Overall, humans have a monthly (ovulatory) fecundity rate ~20%
   1. Chances of pregnancy with average fertility 74% at 6 months, 93% 1 year, 100% 2 years
   2. Chances of pregnancy with 1-5% monthly fecundity 5-25% at 6 months, 20-70% 2 years
4. Rates of Infertility
   1. Of married couples who desire children, 10-15% in USA are childless
   2. About 33% of women who defer pregnancy until mid- to late 30s are unable to conceive
   3. About 50% of women who defer pregnancy until after age 40 are unable to conceive
   4. Estimated >6 million couples in USA with infertility
5. Etiology of Infertility
   1. Ovulation disorders 17%
   2. Tubal disease 23%
   3. Endometriosis 6%
   4. Male factor 25%
   5. Combined factors 5%
   6. Idiopathic 25%
6. Distinct from spontaneous pregnancy loss

B. Prevention of Infertility [3]

1. Lifestyle Changes
   1. Stop smoking
   2. Stop recreational drug abuse
   3. Women reduce vigorous exercise, especially with history of abnormal menses
   4. Men avoid hot tubs, tight briefs, and stop use of anabolic steroids
2. Reduce risk of sexually transmitted diseases (STD)
   1. Strongly recommend use of condoms
   2. Limit number of sexual partners
3. Early screening and detection of STD in patients at risk
   1. All women with abnormal Papanicolaou Smears
   2. Patients with HIV infection
   3. Patients with previous STD
   4. History of preterm labor or ectopic pregnancy
   5. Chlamydia trachomatis infection increases risk for tubal infertility [4]
4. Aggressive evaluation of pelvic pain and progressive dysmenorrhea
5. Remind women that fertily reates decrease after 35 years of age
6. Intrauterine devices do NOT increase risk for tubal infertility [4]
7. Increasing options for preserving fertility in women [34]

C. Evaluation of Infertility

1. Evaluation will yield results which lead to effective therapy in <50% of cases
2. Consider duration of attempted pregnancy and likelihood of conception (see above)
3. Complete medical history and physical examination
   1. Inquiry into frequency and timing of intercourse
   2. Use of lubricants (may be spermicidal or static) during intercourse
   3. Chronic anovulatory syndrome (PCOS)
   4. Endometriosis - also causes infertility
4. Routine laboratory testing
   1. Complete blood count (CBC)
   2. Urinalysis
   3. Serologic testing for syphilis (RPR, VDRL, others)
   4. Glucose level and HbA1c (rule out diabetes and hyperglycemia)
5. Recommendations on Intercourse
   1. No evidence that reducing intercourse frequency to "store up" sperm improves conception
   2. Intercourse advised for 2-3 days after rise in basal body temperature (mid cycle)
   3. Home urinary luteinizing hormone (LH) testing kits can be used to time LH surge
   4. Intercourse is then advised for 2-4 days beginning with LH surge
   5. Oligospermia is the only indication for relative abstinance
   6. Avoid lubricants; warm water may be used instead where required
6. Investigation of Infertility
   1. After discussion of intercourse methods, several tests are used to evaluate infertility
   2. Semen analysis and examination of male genitalia and hormonal status
   3. Documentation of ovulation
   4. Post-coital test - for cervical mucus factors, generally not recommended (see below)
   5. Investigation of female upper genital tract (hysterosalpingography)
7. Additional Tests
   1. These tests are performed if above tests are normal
   2. Thyroid secreting hormone (TSH) level to evaluate for hypothyroidism (common)
   3. Immunological tests
   4. Bacterial cultures of cervical mucus and semen
   5. Endometrial biopsy (to rule out inadequate luteal phase) - done last (invasive)

D. Evaluation of Male Fuction [2]

1. History
   1. Familial syndromes - genetic defects, cystic fibrosis gene abnormalities, others
   2. Abdominal / pelvic surgery possibly suggesting cryptorchidism
2. Physical Examination
   1. Abnormalities of genitourinary (GU) tract - hypospadias, varicoceles (see below)
   2. Penile plaques
   3. Testicular Exam - position, size, consistency (testicular cancer evaluation)
3. Semen analysis
   1. First laboratory evaluation in the investigation of the infertile couple
   2. Sperm assessment is most critical part of evaluation
   3. Semen anti-sperm antibodies should be evaluated in any sperm function
4. Sperm Assessment [6]
   1. Counts, motility, and morphology are critically evaluated
   2. Finding of leukocytes in ejaculate should prompt culture (treat documented infections)
   3. Sperm counts <1 million/mL constitute severe oligospermia
   4. Sperm counts <13.5 million/mL associated with subfertile ranges
   5. Sperm counts >48.0 million/mL associated with normal fertility
   6. Motility <32% and <9% normal morphology associated with subfertile range
   7. Oligospermia, azoospermia associated with increased rates of mutant androgen receptors
5. Azoospermia
   1. Measure basal FSH (LH) and testosterone levels
   2. Elevated FSH - primary germinal epithelium failure
   3. Normal FSH - suggests obstruction (such as vas deferens obstruction)
   4. Presence of >20 CAG trinucleotide repeats in androgen receptor gene is associated with >6X increased risk of infertility due to abnormal sperm
6. Hypogonadotropic hypogonadism (GnRH deficiency) is usually congenital and treatable [20]
7. Testis biopsy is not usually performed and is of questionable benefit
8. Varicocele repair does not appear to improve mail infertility [9]

E. Documentation of Ovulation [1]

1. Any one or more of the following is done in an infertility evalatuion to document ovulation
2. Serum Progesterone
   1. Perform on days 20-24 of menstrual cycle
   2. >3-5ng/mL is positive result
   3. Nearly all pregnancies have serum progesterone levels >10ng/mL
   4. May treat patients with <10ng/mL with clomiphene citrate
3. Urinary LH surge Test
   1. Simple home test which can document surge, around day 20 of cycle
   2. ELISA based dipstick kit is used
4. FSH on Day 3 in Woman [2]
   1. Indicated in woman >34 years old or with prior ovarian surgery
   2. Elevated basal FSH levels (>12-20 IU/L) associated with poor ovarian response to exogenous gonadotropins
5. Basal Body Temperature (BBT)
   1. Progesterone causes increases in BBT
   2. This method is very inexpensive, sensitive, and requires little technology
   3. Generally no longer recommended as part of routine evaluation
   4. Normal biphasic shift has 0.4°F increase in body temperature (taken in AM on awakening)
   5. Luteal phase length should be greater than 11 days
   6. Ovulation actually occurs between lowest and highest points in BBT
6. Endometrial Biopsy
   1. Performed between days 20 and 22 of cycle to demonstrate secretory endometrium
   2. May also be done to document "inadequate" luteal phase
   3. No longer recommended as part of routine evaluation
7. Ultrasound - may be used to evaluate follicular development

[Figure] "Hormonal Changes During the Menstrual Cycle"

F. Other Causes of Female Infertility [1]

1. Chronic Anovulatory Syndrome [14]
   1. Also called polycystic ovary syndrome (PCOS)
   2. Most cases associated with cysts in ovaries
   3. Comprises obesity (~60%), hirsutism, amenorrhea
   4. Insulin resistance and hypertension are very common
   5. Insulin resistance, diabetes, and hypertension all associated with reduced fertility
   6. Elevated levels of LH usually found
   7. Treatment with insulin sensitizing agents (metformin, glitazones) improves menses
2. Anatomic Abnormalities
   1. Cervical incompetence
   2. Congenital uterine anomalies
   3. Adhesions and Leimyomas most common acquired uterine anomalies
3. Hypothalamic Amenorrhea [33]
   1. Amenorrhea occurs in association with exercise in absence of organic disease
   2. Arises with impaired secretion of gonadotropin-releasing hormone (GnRH)
   3. Leads to low or normal gonadotropin (FSH, LH), low estrogen, absent menstrual cycles
   4. Essentially a regression to prepubertal or peripubertal pattern of gonadotropin secretion
   5. Relative energy deficit plays major role in abnormal GnRH secretion
   6. Reduced leptin concentrations appear to be central in this syndrome
   7. Pharmacologic replacement of leptin may lead to normalization of endocrine axes, menses
4. Other Endocrine Disorders
   1. Abnormal Thyroid Function
   2. Diabetes Mellitus
   3. Adrenal insufficiency (Addison's Disease)
   4. Polyglandular autoimmune syndrome type 1 (polyendocrine failure syndrome 1)
5. Chemotherapeutic Agents
   1. Particularly intravenous alkylating agents (such as cyclophosphamide)
   2. Oral contraceptive pill use during chemotherapy treatment may prevent ovarian failure
   3. High dose chemotherapy (often with blood cell transplantation)
   4. Harvesting of eggs is more difficult and is time consuming
   5. Cryopreserved ovarian cortical strips have been used to restore ovulation after high dose chemotherapy for Hodgkin's Disease [12]
6. Relatively Common Genetic Causes
   1. Parental genetic abnormalities: ~2.5%
   2. Turner's Syndromes
   3. Mosaicism
   4. Congenital pituitary insufficiency
7. Single Gene (Uncommon) Genetic Abnormalities [11]
   1. Kallmann's Syndrome (1:50,000)
   2. GnRH Resistance
   3. FSH Deficiency
   4. LH Resistance (LH receptor abnormalities)
   5. Congenital lipoid adrenal hyperplasia
   6. Galactosemia (1:187,000)
   7. Hypergonadotropic hypogonadal ovarian failure [20]
   8. McCune-Albright Syndrome
   9. Aromatase Deficiency (CYP19 mutations)
   10. 17a-hydroxylase Deficiency
8. Premature Ovarian Failure
   1. Accounts for ~15% of primary and ~10% of secondary amenorrhea
   2. Associated with elevated gonadotropin levels and infertily in women <40 years
   3. Various causes indlucing autoimmune, genetic, and chemotherapy induced
9. Infections (Fetal Wastage)
10. Autoimmune Disease

G. Other Causes of Male Infertility [2]

1. Complete Germinal Failure
   1. Radiation Therapy - pelvic > abdominal radiation
   2. Chemotherapy - alkylators, combination therapy
   3. Testosterone may prevent cyclophosphamide induced azoospermia
   4. Orchitis (inflammatory) - mumps, tuberculosis, other
   5. Sertoli Cell Only Syndrome - azoospermia, no sperm lineage cells on biopsy (10-15%)
   6. Maturation Arrest - arrest of spermatogenesis
   7. Cryptorchidism - failed testicular decent, usually congenital
   8. In most of these disorders, FSH levels are >> LH levels
2. Partial Germinal Failure
   1. Medications - chemotherapy, sulfa drugs, abused drugs (including alcohol)
   2. Endocrine Disorders - hypothyroidism, hyperprolactinemia, hypopituitarism
   3. Systemic Illness - usually severe forms, lead to oligospermia
   4. Idiopathic Oligospermia - most common cause of oligospermia
3. Anatomic Abnormalities
   1. Varicocoele
   2. Obstruction of the Vas
4. Disorders of Sperm Function
   1. Pure motility disturbances - poorly understood (likely structural protein defects)
   2. Abnormal Sperm maturation - sperm autoantibodies
   3. Inability of sperm to move through cervical mucus
   4. Non-penetration of sperm into Ova
   5. Up to 15% may be related to Y chromosome abnormalities
   6. An increasing but small proportion of men (7%) will have Y chromosome deletions
   7. Defective zona pellucida induced acrosome reaction (DZPIAR)
5. DZPIAR [16]
   1. ~10% of in vitro fertilization (IVF) failures may be due to DZPIAR
   2. DZPIAR likely to achieve good success with intracytoplasmic sperm injection (see below)
   3. Both zona pellucida and progesterone can induce acrosome reaction
   4. Failure of progesterone induced acrosome reaction predicts failure of IVF
6. Mutations in meiosis regulating protein SYCP3 (very rare) [29]

H. Infertility Treatment Overview [3,7]

1. Treating any underlying factors is critical to success
   1. Radiographic methods, endoscopy or sugery for women with tubal obstruction
   2. Prior to chemo- or radiotherapy, cryopreservation of male semen is relatively simple
   3. Bromocriptine (D1/D2 agonist) recommended for hyperprolactinemia in desired pregnancy [30]
   4. Medical or surgical ablation of endometriosis
   5. Hormonal support of inadequate luteal phase (clomiphene or progesterone)
   6. In couples with infertily after 6-12 months, continued attempts without intervention were superior to ovarian hyperstimulation with intrauterine insemination after 6 months [10]
   7. In these "sub-fertile" couples regardless of treatment, ~33% conceived, ~25% carried [10]
2. Overview of Assisted Reproduction [7]
   1. Ovulation hyperstimulation (superovulation)
   2. Intrauterine insemination
   3. Artificial insemination with sperm for male factor infertility
   4. In vitro fertilization (IVF)
   5. Most of these methods carry high risk of multiple births
3. Ovarian Hyperstimulation
   1. Clomiphene citrate is typically first line in anovulatory women (see below)
   2. Follicle stimulating hormone (FSH) ± LH is often very effective [17,18]
   3. FSH induction (Bravelle®, others) must be followed by hCG
   4. Most effective in women with some ovulatory function and unobstructed genital tract
   5. Gonadotropin induction is associated with high risk of mutliple pregnancy [18]
   6. Increasing age, estrogen levels, and number of follicles correlated with multiple pregnancy
   7. Reducing dose of gonadotropins reduces multiple pregnancy, but also success rates [18]
4. Intrauterine Insemination
   1. Motile sperm suspended in culture medium
   2. Then injected transcervically into uterine cavity
   3. Sperm must be motile
   4. Intrauterine insemination more effective than intracervical insemination [19]
   5. For idiopathic and male subfertility, intrauterine insemination is as effective as in vitro fertilization [19]
   6. Intrauterine insemination is effective and commonly performed
   7. "Post-coital" test for is no longer recommended [2]
5. Combination Superovulation and Insemination [17]
   1. For unexplained infertility and male factor infertily
   2. Unobstructed female genital tract and motile sperm are required
   3. Overall success was 33% pregnancy
6. IVF
   1. Unexplained infertily
   2. Normal or reduced sperm motility
   3. Reduced sperm counts (azoospermia)
7. Intracytoplasmic Sperm Injection
   1. Unexplained infertility
   2. Nonmotile or reduced motility sperm
   3. Other Sperm Abnormalities
8. Preservation of Fertily in Cancer Patients [34]
   1. Ooporectomy and cryopreservation
   2. Ovariopexy during pelvic irradiation
   3. Aspiration of immature oocytes without stimulation (followed by in vitro techniques)
   4. Delay in aspiration (4-6 weeks) of oocytes with stimulation
   5. Tissue removal and cryopreservation, then thawing and in vitro or in vivo techniques

I. Treatment of Anovulation

1. 10-15% of all infertile women are anovulatory
2. Divided into primary amenorrhea, secondary amenorrhea, and oligomenorrhea
3. Primary Amenorrhea
   1. Many patients have normal secondary sex characteristics
   2. Failed process of ovulation only
   3. These patients should recieve im injection of 100-200mg progesterone
   4. Normally this progesterone injection will cause withdrawal bleeding
   5. If estrogen pathway not functional, then endometrium not developed, thus no bleeding
4. Patients with secondary amenorrhea should have similar progesterone injection
   1. After progesterone challenge, ~60% of patients will have uterine bleeding
   2. Patients with uterine bleeding should be treated with clomiphene citrate (Clomid®)
5. Clomiphene Citrate (Clomid®)
   1. Clomiphene is an estrogen receptor modulator that induces ovulation
   2. Overall, ~80% of women will ovulate on clomiphene
   3. Of these, ~75% have term pregnancies, ~25% abort from drug
   4. Complications: ~5% multiple pregnancies, ~8% ovarian cysts, ~3% fetal abnormalities
   5. Careful monitoring can reduce risk of multiple pregnancies
   6. Side effects: vasomotor flushing (10%), abdominal complaints (6%), breast discomfort (2%)
   7. Clomiphene is started on 5th day of the cycle for five days
6. Other Ovulation Inducing Agents
   1. Human chorionic gonadotropin (HCG) can be given 7 days after clomiphene maximum
   2. Perganol (gonadotropins) induces ovulation in ~100% of patients
   3. Risks of other perganol are similar to those of clomiphene (% may be slightly higher)
   4. Cyst formation, ovarian hyperstimulation, may be reach ~10% (see below)
   5. Gonadtropin releasing hormone (GnRH) can be used iv or sc as well
7. Ovulation inducing therapy should be tried for 3 cycles prior to further evaluation
8. Superovulation is combined with uterine insemination as described above
9. No increase in risk for ovarian cancer [3]
10. Ovarian Hyperstimulation Syndrome (see below)

J. Ovarian Hyperstimulation Syndrome (OHS) [3]

1. Most serious medical complation of iatrogenic superovulation
2. Genetic form of OHS [27,28]
   1. Mutations in follicle-stimulating hormone receptor (FSH-R) found
   2. Leads to hypersensitivity to chorionic gonadotropin (HCG)
   3. Normally, FSH-R does not respond to HCG
   4. Mutant FSH-R responds to HCG with similar efficiency as FSH
3. Pathophysiology
   1. Believed that abnormally elevated renin production by ovary initiates syndrome
   2. Vascular endothelial growth factor (VEGF) production by ovary increases vascular permeability
   3. Cystic enlargement of ovaries and marked increase in vascular permeability
   4. Leads to extravasation of fluid, pelvic ascites (third spacing)
   5. This causes hemoconcentration, hypovolemia and hypercoagulation
   6. In addition to ascites, pleural and pericardial effusions may occur
   7. In severe hypovolemia, hepatic and renal dysfunction and hepatorenal syndrome can occur
4. Symptoms
   1. Present with abdominal distention, nausea, vomiting, dyspnea
   2. Venous and arterial thromboses can occur
5. Treatment
   1. Supportive care with maintenance of intravascular volume critical
   2. Paracentesis to relieve abdominal pain and pulmonary compromise
   3. Short term prophylaxis against thromboembolism (low molecular weight heparin) advised
   4. Termination of pregnancy may be required in very severe cases

K. In Vitro Fertilization (IVF) [5,7,8]

1. IVF includes a variety of methods of "Assisted Reproductive Technology" [5]
   1. Overall success rate is about 25% per cycle of IVF in USA, ~17% in Europe
   2. Over 80,000 IVF cycles in USA in 2001
   3. Over 48,000 babies by IVF in 2003 in USA
   4. With IVF in USA, 36% lead to multiple births per delivery
   5. About 1% of births are through IVF at the present time
   6. Overall outcomes of children born through IVF are good
   7. Complications in children born to IVF mainly related to high birth order
   8. Slight increase in urogenital malformations present in boys, even in singleton births
2. Several different methods for augmenting rates of sperm-egg fertilization [3]
   1. Gamete intrafallopian transfer - oocytes and sperm placed into fallopian tube
   2. Zygote intrafallopian transfer - fertilized oocytes placed into fallopian tube
   3. Tubal embryo transfer - cleaving embryos placed into fallopian tube
   4. Peritoneal oocyte and sperm transfer - oocytes and sperm placed into pelvic cavity
   5. Intracytoplasmic sperm injection (ICSI, also called sperm extraction; see below)
   6. Testicular sperm extraction - for azoospermia
   7. Microsurgical epididymal sperm aspiration - for azoospermia
   8. Transfer of blastocyst stage superior to cleavage-stage embryos [13]
3. Factors Associated with Reduced Success Rates
   1. Age <25 (slight reduction) and >30 years (increasing failure with age)
   2. Rate of live births to women <35 years is 40-49% (using woman's own eggs)
   3. Rate of live births to women 43 years old is ~5%
   4. Lack of prior pregnancy or live birth
   5. Increasing number of failed previous cycles
   6. Male sperm abnormalities
   7. Increasing duration of infertility
4. High Rate of Multiple Births with Standard IVF [21,22]
   1. In general, more than two embryos are transferred (>1 often fails)
   2. Multiple births occur in 27-33% of cases (compared with ~1% of controls)
   3. When >4 eggs are fertizilized and available for transfer, transfer of 2 embryos versus >2 embryos reduces multiple births without reducing overall chance of a birth
   4. Multiple births lead to increased risk of prematurity and low birth weight [23]
   5. Slightly higher incidence of low birth weight amongst singleton births [23]
   6. In women <36 years, transferring one fresh embryo, followed if needed by one frozen- and-thawed embryo reduces in only 0.8% multiple-birth rate [31]
   7. Transfer of single blastocyst (day 5) versus cleavage-stage (day 3) embryo associated with 32% versus 21% delivery and 0/87 versus 2/87 twin births [13]
   8. Mild ovarian stimulation using GnRH antagonist combined with single embryo transfer ("mild IVF") gave similar pregnancy and live birth rates, reduced (0.5%) multiple births [15]
5. Complications [22,24]
   1. Ovarian hyperstimulation syndrome (see above) ~5% of IVF situations
   2. IVF singleton pregnancies have increased complication rates compared with controls
   3. Very preterm births were ~3.5X more likely with IVF
   4. Very low birthweight (<1500 gm) were ~2.6-4.4X more likely with IVF [23]
   5. All and major malformations were ~2.0X and 1.3X more common with IVF versus matched infants born to natural pregnancies
   6. Overall neurological sequelae risk 1.7X (1.4X for singletons) [25]
   7. Cerebral palsy risk increased 2.8-3.7X [25]
   8. Risk of neurologic sequelae of any type largely associated with multiple births [25]
   9. No increase in childhood cancer in IVF group
6. Preimplantation Genetic Screening
   1. To choose embryos with normal karyotype in patients (with genetic disorders) [32]
   2. In women age 35-41 without known genetic abnormalities, preimplant genetic screening Is associated with significantly poorer fertily and birth outcomes [35]

L. Intracytoplasmic Sperm Injection (ICSI) [2,25,26]

1. ICSI is a particularly useful approach for abnormal sperm motility and other sperm abnormalities ("male factor" abnormalities")
2. Now used in majority of IVF cycles as it is more efficient than simple egg/sperm coculture 3, Dramatic increases in use over past 12 years, related to state-mandated insurance coverage
3. Of successful injections, overall pregnancy rate was 37% for ICSI [25]
4. Potential for increased DNA damage on sperm introduction into egg
   1. Malformations occured ~2.6% but no increase in sex chromosome abnormalities [25]
   2. No differences in congenital malformations or major health problems at one year
   3. In another study, 2X risk of major birth defects with ICSI as natural births [24]
5. At one year, 17% of children by ICSI versus 2% by IVF had mild developmental delays
6. Therefore, children conceived by ICSI may require more careful attention in early years

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