Medical brain notes 42

  Infertility Infertility  affects approximately 15% of reproductive-age I   couples in the United States. Reproductive age gen-erally encompasses ages 15 to 44 years, although pregnancy can occur outside of this age range.  Infertilityis the failure of a couple to conceive after 12 months of frequent, unprotected intercourse.  The probability of achieving a preg-nancy in one menstrual cycle is termed  fecundability,  and is estimated to be 20% to 25% in healthy young couples. Similarly,  fecundity  is the probability of achieving a live birth in one menstrual cycle. Fecundability and fecundity both decrease over time; in other words, the probability of conceiving in a given menstrual cycle decreases as the dura-tion of time to achieve conception increases (Fig. 38.1). After 12 months without using contraception, approximately 50% of couples will conceive spontaneously within the following 36 months. If a couple does not conceive by this...

  ETIOLOGY OF INFERTILITY   Successful conception requires a specific series of complex events:   ovulation of a competent oocyte, (2) production of competent sperm, (3) juxtaposition of sperm and oocyte in a patent repro-ductive tract and subsequent fertilization, (4) generation of a viable embryo, (5) transport of the embryo into the uterine cavity, and (6) successful implantation of the embryo into the endometrium  (Fig. 38.2).   Any defect in one or more of the essential steps in reproduc-tion can result in diminished fertility or infertility. Furthermore, some degree of male infertility is implicated in up to 40% of couples. Conditions that affect fertility are divided into four main categories:   ·       Female factors (65%)   ·       Male factors (20%)   ·       Unexplained or other conditions (15%)

  EVALUATION OF INFERTILITY   The most common causes of male and female infertility are investigated during the initial evaluation of infertility. It is important to recognize that more than one factor may be involved in a couple’s infertility (Table 38.1). As with any medical condition, a careful history and evaluation should reveal factors that may be involved in a couple’s infertility, such as medical disorders, medications, prior surgeries, pelvic infections or pelvic pain, sexual dysfunc-tion, and environmental and lifestyle factors (e.g., diet, exercise, tobacco use, drug use).   The timing of the initial evaluation depends primar-ily on the age of the female partner and a couple’s risk fac-tors for infertility.  Because there is a decline in fecundity withadvancing maternal age, women over age 35 may benefit from a preliminary evaluation before 12 months of attempted conception.  The initial assessment and treatment of infertility is com-monly provided by...

  MALE INFERTILITY   Because male infertility is common, it is important to also perform a  semen analysis  when initiating evaluation of the female partner. The semen specimen is usually obtained by masturbation after 2 to 3 days of abstinence; frequent ejac-ulation may lower the sperm concentration. It is important to collect the entire ejaculate, because the first part contains the greatest density of sperm. Analysis of the specimen should be performed within 1 hour of ejaculation (see Table 38.1). The standard semen analysis evaluates the quantity and quality of seminal fluid, sperm concentra-tion, and sperm motility and morphology. Normal semen measurements have been established by the World Health Organization (Table 38.2). A normal semen analysis excludes a male cause for infertility in more than 90% of heterosexual couples. Certain abnormalities identified by the semen analysis are associated with specific etiologies of male infertility (Table 38.3). Sperm fu...

  UNEXPLAINED INFERTILITY   For some couples, comprehensive evaluation of both partners does not identify an etiology for their infertility. Specifically, test results identify a normal semen analysis, evidence of ovulation, a normal uterine cavity, and patent fallopian tubes.  Approximately 15%of couples are considered to have unexplained infertility. This diagnosis usually signifies the presence of one or more mild abnormalities in the highly orchestrated sequence of events that results in successful conception. These abnor-malities may lie below the level of detection of current tests or may not be detected by current tests. These couples have a low rate of spontaneous conception, approximately 1% to 3% each month; this rate is influenced by the age of the female partner and the duration of infertility. If laparoscopy is performed on the female partner, subtle abnormalities such as pelvic adhesions and mild endometriosis may be identified and treated. However, it is re...

  TREATMENT   A couple’s infertility may be related to one or several abnormalities in one or both partners.  Numerous medical,surgical, and  assisted reproductive technology (ART)  ther-apies are available for treating the infertile couple.  For coupleswith unexplained infertility, empiric treatment may over-come the negative effects of one or more mild abnormal-ities. These couples, as well as the majority of infertile couples, tend to proceed through fertility treatment in a stepwise fashion, starting with conservative and then with more aggressive ovarian stimulation, inseminations, and eventually proceeding to IVF (explained below).   Surgical procedures are indicated in certain circum-stances. If a woman presents with pelvic pain and infertility, laparoscopy may be used to identify and treat the cause of her pelvic pain as well as evaluate pelvic anatomy from a fer-tility standpoint. If an obstructed fallopian tube is identified with HSG, it may ...

  COUNSELING   A team approach is frequently helpful in ensuring that patients receive an adequate workup and appropriate counseling. Counseling of patients who are treated with ART should include information regarding the risk of multiple gestation, ethical issues surrounding multifetal pregnancy reduction, and adoption. Clinicians should also be famil-iar with any state laws regarding infertility services and treatment or insurance coverage.