Prenatal Care/Labor and Delivery/Contraception - FMBR 2nd Edition

Educational Objectives

Program Objectives

Upon completing this educational activity, participants will be better able to:

1. Understand and appropriately respond to the wide range of medical and psychological issues frequently encountered by practicing family physicians.

2. Select relevant tests or diagnostic procedures for patients seeking care.

3. Utilize the best evidence-based knowledge to achieve optimal therapeutic goals.

4. Prescribe effective drugs and therapeutic procedures.

5. Integrate newly acquired knowledge into routine practice patterns.

Summary

Prenatal Care/Labor and Delivery/Contraception

Beth Choby, MD, Associate Professor, Department of Family Medicine and Director of Research and Procedural Training, University of Tennessee College of Medicine and Health Science Center, Chattanooga, TN

Contraception and screening guidelines: it is important to be familiar with options for contraception, with guidelines for cervical cancer screening, and with updates on administration of human papillomavirus vaccine; an estimated 50% pregnancies in the United States are unintended, so unintended pregnancy impacts females of all ages, and socioeconomic and marital statuses; although unintended pregnancies were often associated with adolescence, 41% of pregnancies in 35- to 39-yr-old women and 50% of those in women over 40 are unintended; a recent and significant decrease in the adolescent pregnancy rate has been attributed by the Pew Research Center to reasons including decreased sexual activity in teens, better educational opportunities, and availability and use of more effective contraception

Risks and Benefits of Contraceptives

Barrier methods: these methods include diaphragms, contraceptive sponges, male and female condoms, and cervical caps

Advantages: these include contraceptive benefit, lack of hormone exposure, as-needed-only use, and decreased sexually transmitted infection (STI) risk with condoms; barrier methods were also an option for women whose medical conditions preclude hormonal contraceptive use

Disadvantages: these include the need to be fitted for, eg, diaphragms and cervical caps, decreased spontaneity, decreased sexual sensitivity with condoms; relatively high failure rates with typical use; failure rates are 18% for male condoms, 21% for female condoms, 12% with diaphragms, and 12% and 24% for the contraceptive sponge in nulliparous and parous women, respectively

Continuous hormonal contraception: these include oral contraceptives (COCs), patches and rings, and progestin-only pills; benefits of COCs — both contraceptive and medical benefits, including treatment of abnormal uterine bleeding and dysmenorrhea, polycystic ovarian syndrome, menstrual-related conditions, and, in some preparations, acne vulgaris; most COCs contain 30 to 35 mcg of ethinylestradiol, although some types have lower doses ranging from 10 to 25 mg; lower-dose formulations are occasionally used in perimenopause routines, although breakthrough bleeding and amenorrhea are more common than with the 30 to 35 mcg pills; progestins and COCs vary based on the amount of progesterone and androgen-receptor binding; third-generation progestins like Norgestimate and desogestrel have less androgenic binding and fewer adverse effects on lipids; it is less well understood whether these progestins increase thromboembolic risk; drospirenone, additionally, has antimineralocorticoid activity that gives a slight benefit related to body weight and blood pressure

Advantages: these include low cost, availability of generics, and familiarity; both the Centers for Disease Control and the World Health Organization have developed tables comparing hormonal contraceptive options based on patients’ specific characteristics; these tables are easily accessed online and there is also an phone app that can be downloaded

Disadvantages and limitations: COCs are best avoided in specific patient populations including women over 35 years of age who smoke, women with migraines with aura, and individuals with conditions that include thromboembolic disease, cirrhosis, cardiomyopathy, uncontrolled hypertension, history of stroke, complicated vascular disease, or prolonged immobilization; progestin-only pills are good alternatives if combination pills are contraindicated due to estrogen effects or for newly postpartum mothers who are initiating lactation; COCs are considered less effective than long-acting reversible contraception (LARC), with about 9% of women experiencing unintended pregnancy within the first year of typical use

Contraceptive patches and vaginal rings: both the transdermal patch and vaginal ring are effective methods for hormonal contraception; the patches are applied once weekly for 3 weeks and then removed from 1 week when menses should occur; the contraceptive vaginal ring is inserted for 3 weeks and removed the fourth week when menses occur

Advantages of patches: autonomy; not needing to remember a daily pill; failure rates are similar to COCs

Disadvantages of patches: patches can cause application site reactions and more breast tenderness compared with COCs; patches result in higher total estrogen exposure compared with COCs and even though transdermal delivery causes fewer peaks in troughs of estrogen, there is a higher total estrogen exposure compared to COCs; a 2017 review in the International Journal of Women’s Health found that risk of venous thromboembolism (VT) with patches was twice that of COCs; however, absolute overall VT risk for both groups was low

Advantages of rings: the effectiveness of rings is also similar to COCs and there is no need to remember a daily pill

Disadvantages of rings: these include increased vaginal discharge and a dislike of inserting the ring (especially a concern in adolescents)

Depot medroxyprogesterone acetate (DMPA): this can be given every 13 weeks either intramuscularly, a (150 mg/mL), or subcutaneously (104 mg/0.65 mL); DMPA is not considered a LARC

Advantages: DMPA is an option for women who find other contraception methods challenging or who have contraindications to the use of estrogen; Depo-Provera is also helpful for treating dysmenorrhea and other menstrual disorders because around 70% of women using it become amenorrheic over time

Disadvantages: there is a need for regular health care provider contact, potential for delayed fertility after use, and reversible bone mineral density changes; DMPA has a warning as to use longer than 2 years due to concerns about decreased bone mineral density although this decrease tends to reverse once the method is discontinued

LARCs: these include progesterone implants or the etonogestrel implantable rod and intrauterine devices (IUDs) including the copper IUD or levonorgestrel system (IUS); the etonogestrel single-rod implant is effective for 3 years; recent studies indicate that it provides comparable systemic levels of progestin with varying body mass indexes (BMIs) and the most recent 2016 US Medical Eligibility Criteria for Contraception listed the implant as compatible with obesity as well as all BMIs

Advantages: LARCs have a pregnancy rate of less than 0.5%, although nearly 15% of women may prematurely discontinue the method due to irregular vaginal bleeding; additional benefits include the ability to use these in women for whom estrogen is contraindicated; LARCs also has no impact on bone density and a possible usefulness for dysmenorrhea

Disadvantages: LARCs are relatively expensive, with costs that reach $800 for placement and $300 for removal, although insurance and patient assistance programs are available to help defray costs

Intrauterine devices: there are 3 types of IUDs currently available; the copper IUD is FDA approved for 10 years of use whereas the levonorgestrel IUS releases 20 mcg of hormone daily and is approved for 5 years of use; Skyla, which has a smaller diameter and is sometimes chosen for nulliparous patients, was FDA approved in 2013 as the newest progestin IUD; absolute contraindications for IUDs are few and include recent puerperal sepsis or immediate placement following a septic abortion; nulliparous women can safely use IUDs; prior to insertion, neither routine antibiotics nor cultures for SGIs are necessary; IUDs may be inserted in the immediate postpartum period although device expulsion rates are higher than in nonpregnant patients

Advantages: levonorgestrel IUDs are additionally beneficial in situations of dysmenorrhea, menorrhagia, irregular bleeding, and endometrial hyperplasia; effectiveness is high, with less than 0.2% risk of pregnancy in the first year of use with the levonorgestrel IUS, and 0.8% for the copper T IUD

Disadvantages: disadvantages include higher ectopic risk if pregnancy does occur; in women who become pregnant with an IUD in place, localization of the gestation and IUD removal in the case of intrauterine pregnancy decreases risk of both infection and pregnancy loss

Emergency contraception (EC): EC is defined as any medication or device used to reduce pregnancy risk after unprotected intercourse or contraceptive failure; this is intended as an emergency rescue method rather than primary contraception; 4 types of EC are currently FDA approved in the United States including the copper IUD and 3 oral regimens; oral regimens include ulipristal acetate (Ella), levonorgestrel (Plan B and Plan B One-Step), and the Yuzpe method, which includes estradiol plus levonorgestrel oral contraceptives; mifepristone or RU-486 is an oral antiprogestin that can be combined with misoprostol for first trimester medical abortion but is not available in pharmacies in the United States and requires dispensation by a certified health care provider

Copper IUD: this is the most effective and only nonhormonal EC method for preventing pregnancy; it has a pregnancy rate of 0.009%; the mechanism includes inhibition of sperm motility; it should be placed within 5 to 7 days of unprotected intercourse (earlier is better); it may be used for long-term contraception for up to 10 years once placed; its effectiveness does not depend on BMI or weight; disadvantages include cost (ranges from $500 to $1000), the need for an appointment with the provider within 5 days of unprotected intercourse, and heavier bleeding and/or cramping with use; risks are uncommon and include pelvic infection, expulsion, and perforation, which affects 1 in 1000 women; women who are pregnant have active pelvic infection or copper allergy (including women with Wilson disease), should not use a copper IUD for EC

Ulipristal acetate (UPA; Ella 1): one of the most effective hormonal methods for EC; approved in the United States in June 2010, it has a pregnancy rate ranging from 0.9% to 2.1% and costs around $30 to $35; the recommended dose is 30 mg once orally; it is approved for use within 5 days of unprotected intercourse and is equally effective over this entire period; the mechanism of action involves prevention or delay of ovulation prior to the luteinizing hormone (LH) surge; it directly inhibits follicular rupture when given after the LH surge but prior to the LH peak; because follicular rupture is delayed by 4 to 10 days, a backup form of contraception is needed until the next period; ulipristal binds progesterone receptors, may interfere with other progesterone-containing contraceptives; UPA is less effective in women with a BMI over 30 and is considered ineffective in those with a BMI greater than 35 (the failure rate in this group is 2.6%, although this rate is lower than that seen with levonorgestrel EC)

Levonorgestrel/Plan B: Plan B is a 2-dose version of 0.75 mg tablets given orally 12 hours apart; Plan B One-Step is a 1.5 mg single dose; these are most effective when given immediately after unprotected intercourse with failure rates ranging from 0.6% to 3.1%; these are less effective over time, preventing 95% of pregnancies when given within 24 hours, 85% when given within 24 to 48 hours, and only 58% if taken within 49 to 72 hours of unprotected intercourse; these can be used for up to 5 days or 120 hours, although efficacy declines over time and levonorgestrel is less effective than UPA at 120 hours; the single dose 1.5 mg regimen is as effective as the 2-dose regimen and the preferred method for teens; the mechanism of action involves prevention of follicle rupture and ovulation, although it is not in abortifacient and has little to no effect once the LH surge has begun; levonorgestrel is less effective when the BMI is over 25 and ineffective if the BMI is over 30; at a BMI over 30, the failure rate is 5.8%; cost of the regimen is around $30 to $35

Yuzpe method: this is the least effective method of EC and has the greatest number of side effects; it should be offered only if no other options are available; it is most effective within 72 hours of unprotected intercourse; various combinations of ethinylestradiol and levonorgestrel can be prescribed, although combined EC products are no longer available

Cervical cancer screening: recent evidence indicates that there are potential harms for inappropriate cervical cancer screening including increased false-positive test results and unnecessary diagnostic procedures, future poor pregnancy outcomes, increased health care expenditures, and psychological anxiety and stress in patients; increasing knowledge about the natural course of HPV infection, especially in late adolescents, also has changed recommendations

Papanicolaou test recommendations: since 2012, the American Society for Colposcopy and Cervical Pathology (ASCCP), the American Cancer Society, the US Preventive Services Task Force, and the American College of Obstetricians and Gynecologists have published similar guidelines that discourage Papanicolaou test screening in low-risk women including those under 21 or over age 65; they recommend increasing screening intervals from 3 to 5 years with cytology every 3 years for women aged 21 to 29 and the option of cytology alone or HPV cotesting with cytology every 3 years for women aged 30 to 65; after age 65, screening can be discontinued after 3 consecutive negative cytologies or 2 consecutive negative HPV tests within the past 10 years with the most recent screening being done within the past 5 years; screening can be discontinued at any age after total hysterectomy for a benign indication if the patient has no prior histories of cervical intraepithelial neoplasia (CIN) 2, CIN 3 or cervical cancer; for women with a history of a high-grade precancerous lesion (these would be women with CIN 2 or 3), routine screening should continue for at least 20 years following spontaneous regression of the cervical lesion or treatment of the cervical lesion; primary HPV testing is also now FDA approved as an alternative in women 30 to 65 years of age, although this recommendation was not part of the 2012 guidelines; a 2017 study in gynecologic oncology found no increase in population level rates of invasive cervical cancer among women aged 21 to 25 years; incident rates were very low and were not found to have increased over the past years

HPV vaccination: the Advisory Committee on Immunization Practices (ACIP) guidelines for HPV vaccination have also recently changed; the nonavalent HPV vaccine (Gardasil 9) is recommended by ACIP for both males and females aged 9 to 26; children with a history of sexual abuse or assault should begin vaccination at age 9; in October 2016, ACIP approved a 2-dose regimen schedule, which consists of the initial dose and then the repeat dose in 6 to 12 months for adolescents who are starting the HPV series prior to their 15th birthday; those starting the vaccine after age 15 or any immunocompromised adolescents should still receive the traditional three-dose regimen

Pregnancy

Preconception: important to discuss folic acid use at preconception visits because folic acid provides protection against neural tube defects, which affect around 3,000 pregnancies in the United States annually; one-third of these gestations are either electively terminated or spontaneously lost

Folic acid (B9): water-soluble vitamin that enhances cellular proliferation and contributes to neural tube closure; it has a strong impact in regulating epigenetic gene transcription that controls neural tube closure; when started 1 month prior to conception and continued through the first trimester, folic acid is highly protective against neural tube defects (NTDs); dietary fortification of flour with folic acid does not provide sufficient amounts and the United States Preventive Services Task Force recommends that healthy normal-weight women take folic acid at 0.4 to 0.8 mg per day; prenatal vitamins generally contain around 0.8 to 1 mg of folic acid; guidelines vary on how far and advanced to start supplementation (ranging from 1 month to 6 months preconception); because 50% of US pregnancies are unplanned and neural tube closure occurs in the first 6 weeks of gestation, many women presenting for care after this time miss the protective effect; certain women should receive a 4 to 5 mg daily dose of folic acid in the preconception period and during the first trimester; women with a prior pregnancy with an NTD or a close relative with NTD require this higher dose; when prior pregnancy is impacted by an NTD, recurrence risk in a future pregnancy increases 40 fold; other indications for increased folic acid dose include obesity and genetic mutations in the folic acid metabolic pathway or folate receptors; an example of this would be the methylene-tetrahydrofolate dehydrogenase 1 (MTHFD1) gene deficiency; also, women with poorly controlled type 1 or type 2 diabetes, passive or active smoking, celiac, or Crohn disease, and women using oral contraceptives; women taking medications that have antifolate activity, eg, antiepileptic drugs (especially carbamazepine, valproate, or barbiturates), sulfonamides, and methotrexate, also should take the 4 to 5 mg folic acid dose; to date, research is not indicating increased speed or risk for maternal exposure to this higher dose of folic acid; after the first trimester is over, patients can transition back to standard 0.4 mg dose; in women with amenorrhea or a missed period, confirming the pregnancy and establishing pregnancy dating is critical

Pregnancy testing and early pregnancy: beta-human chorionic gonadotropin (hCG) is a highly sensitive and specific test for pregnancy; it is positive at day 21 to 22 after the last menstrual period as implantation begins or by 8 days postovulation; in normal early gestations, hCG levels double every 1.4 to 2.1 days, although a rise as low as 55% on 48 hours may be seen; early transvaginal ultrasonography findings should show a gestational sac by 5 weeks, 0 days, a gestational sac and a yolk sac by 5 weeks and 4 days of pregnancy, a gestational sac plus a yolk sac and a 3-mm embryo by 6 weeks, 0 days of pregnancy, and an embryo with cardiac activity and visible body movements at 8 weeks and 0 days; it is important to remember that between 5.5 and 6.5 weeks gestation, an embryonic heart rate of less than 100 beats per minute is normal and by 8 weeks, the fetal heart rate is up to approximately 180 beats per minute

First trimester: in patients with bleeding and/or cramping, there are additional considerations; differentiating intrauterine pregnancy from an ectopic or spontaneous pregnancy loss or miscarriage can be challenging; if pregnancy viability and location needs to be decided at a single point in time, a progesterone level can be a useful test to differentiate a viable from a nonviable pregnancy while transvaginal ultrasonography is the most useful single test to differentiate intrauterine from ectopic pregnancy; progesterone levels less than 20 nanomoles per liter are 75% sensitive and 98% specific for predicting nonviable pregnancy; progesterone levels do not, however, reliably distinguish spontaneous pregnancy loss from ectopic

Spontaneous miscarriage: 15% of diagnosed pregnancies end in spontaneous miscarriage, also called spontaneous pregnancy loss or spontaneous abortion; they are categorized as threatened, inevitable, incomplete, or complete; these are further classified as either sporadic or recurrent (recurrent is generally considered over 3 losses); with threatened miscarriage, there is bleeding but no passage of tissue or cervical dilatation; half of women go on to miscarry, although the risk decreases if fetal heartbeat has been detected; inevitable miscarriage involves bleeding in the setting of cervical dilatation; in an incomplete miscarriage, products of conception have not yet been expelled; complete miscarriage is diagnosed with bleeding and passage of products of conception has already occurred; nonviable pregnancy is likely with ultrasonography findings of an embryo measured at greater than 7 weeks estimated gestational age that has a heart rate less than 85 beats per minute; if a small sac size relative to the size of the embryo is noted, if there is an enlarged or abnormally shaped yolk sac or a subchorionic hemorrhage indicating bleeding under the placental implantation site, or if hCG levels either falling or not rising appropriately, these findings may help confirm a nonviable pregnancy

Managing incomplete miscarriage: can include expectant management, pharmacologic therapy, or surgery with aspiration in the office or a surgical dilatation and curettage generally done as an outpatient surgical procedure; most women complete a miscarriage by 14 days, but some opt for surgery while others wish to avoid intervention; women who are managed expectantly should be counseled about bleeding and have close follow-up; misoprostol, a prostaglandin E1 analog, has been used off label for first trimester incomplete miscarriage; an initial dose of 800 mg is given with a repeat dose administered no sooner than 3 hours and typically within 7 days if there is no response from the first dose; a 2012 Cochrane review showed that misoprostol was only slightly inferior to surgery for successful completion of miscarriage although secondary outcomes did show 2 more days of bleeding and more unplanned surgery in the women in the misoprostol group compared with those in the surgical group; patients treated with misoprostol overall required markedly less surgical intervention with a relative risk of 0.06 and a confidence interval of 0.02 to 0.13

Ectopic pregnancy: affects 1% to 2% of gestations and is the leading cause of maternal death in the first trimester of pregnancy; it accounts for 9% of US pregnancy-related deaths; the strongest risk factor for ectopic is previous tubal surgery; other risk factors include history of sterilization, prior ectopic pregnancy, current IUD use, history of pelvic inflammatory disease, maternal age >40, and smoking; the most common symptoms of unruptured ectopic are first trimester bleeding and abdominal pain, so a pregnancy test is essential in female patients of reproductive age with abdominal pain; if the pregnancy test is positive, clinical history should focus on dating and changes in the patient’s current symptoms and physical examination; the physical examination should include an abdominal and pelvic examination to assess for cervical motion tenderness, rebound or guarding, cervical dilation, or any type of vaginal bleeding; the cervical os should be assessed with a speculum examination for bleeding or tissue passage and hemodynamic stability should be assessed by vital signs

Confirming ectopic pregnancy: hemodynamically unstable patients should receive emergent surgical assessment; a quantitative hCG test and transvaginal ultrasonography are prudent for hemodynamically stable patients; ectopic pregnancy is confirmed if the gestation is seen outside of the uterus, although heterotopic pregnancy (concomitant ectopic and intrauterine gestation) occurs in 1 in 30,000 pregnancies; if transvaginal ultrasonography is nondiagnostic, a quantitative hCG test can be helpful; discriminatory levels are usually set at around 1,500 to 2,000 IU per liter, at which an intrauterine pregnancy should be visible on transvaginal ultrasonography; if the hCG level is below the discriminatory index and an ultrasonography is nondiagnostic in an otherwise stable patient, repeating the hCG after 48 hours is reasonable; if the hCG is above this level and there is no mass or intrauterine pregnancy seen on ultrasonography, then a similar path may be followed; worsening abdominal pain or any changes in vital signs warrants immediate surgical evaluation

Treatment: includes either methotrexate, open or laparoscopic surgery, or expectant management; choice of therapy depends on patient’s hemodynamic stability and preferences for therapy; a 2007 Cochrane review showed no difference in success rate, subsequent fertility, or tubal patency between women treated with methotrexate or laparoscopic salpingectomy; for patients who wish to preserve fertility, salpingostomy is preferred when possible; expectant management is not currently recommended as a routine treatment for ectopic pregnancy outside of research protocols; methotrexate may be used, but patient selection is key

Use of methotrexate: failure is likely if the heartbeat in an embryo can be seen, if the gestational sac is greater than 3.5 cm, if free blood is seen in the peritoneum, or if the initial hCG levels are greater than 1,500 to 2,000 IU per liter; most experts recommend surgical treatment if the initial hCG levels are greater than 2,000 IU per liter with the confirmed ectopic pregnancy; contraindications include maternal pulmonary or hepatic disease, renal disease, known allergy, immunodeficiency, severe anemia, or thrombocytopenia, or active lactation; a complete blood count, creatinine, glomerular filtration rate test, and liver function tests are ordered to assess appropriateness for methotrexate; adverse effects include abdominal pain, nausea, vomiting, and stomatitis; hCG levels should drop by 15% from day 4 to 7 after injection, although levels often initially plateau or increase prior to this fall; if the decrease in hCG does not occur, an additional methotrexate dose or surgical therapy is required

Blood type and screen: all women with a positive pregnancy test and first trimester vaginal bleeding should have a blood type and screen; woman who are Rh-negative should receive RhoGAM regardless of pregnancy outcome; generally the first trimester dose of RhoGAM is 50; if the pregnancy is affected by first trimester bleeding and progresses normally, RhoGAM is also indicated in Rh-negative women at both 28 weeks and then postpartum if the infant is Rh-positive

Follow-up for Pptients with miscarriage and ectopic pregnancy: hCG levels should be monitored; following ectopic pregnancy, hCG levels are generally checked weekly and usually take around 5 weeks to reach 0, sometimes taking as long as 7 weeks; hCG are often checked 1 month after miscarriage

Recurrent pregnancy loss (RPL): some women are affected by RPL; general definition is 3 pregnancy losses prior to 20 weeks gestation that exclude ectopic, molar, or pregnancies where the hCG is detected but no embryo develops (biochemical pregnancy); RPL can be primary (no prior live birth) or secondary (with previous delivery of a live infant); clinically recognized pregnancy loss occurs in 15% to 25% of all pregnancies but the rate approaches 57% if preclinical losses are included; age influences risk with half of pregnant women over age 40 experiencing miscarriage; RPL has been associated with numerous causes but a definitive diagnosis is possible in only half of patients; congenital and other uterine anomalies such as uterine didelphys or bicornuate uterus due to Mullerian tract anomalies are more common in women with RPL; history of salpingogram (HSG), saline infusion sonogram (SIS), diagnostic hysteroscopy, magnetic resonance imaging (MRI) or 3-dimensional ultrasonography is often preferred as part of the initial RPL evaluation; other workup may include evaluation for antiphospholipid syndrome or parental karyotype and a karyotype can identify 3% to 4% of couples affected by balance translocation; thyroid function and diabetes screening is also recommended; counseling about lifestyle factors may impact RPL risks; assessing emotional well-being is critical and psychological support during weekly medical visits is helpful

Prenatal intake and screening: at prenatal intake, laboratory work and assessment usually includes the blood typing Rh, complete blood count with differentials, Rubella titers, screening for sexually transmitted infections (HIV, syphilis, hepatitis B, gonorrhea, and chlamydia), a urine culture, and cervical screening if no cytology has been done within the past 3 years; an early glucose challenge test can be done with intake in women at higher risk; first trimester genetic screening can be done between 11 and 13 weeks; patients at risk for or with a family history of genetic disorders should be counseled and referred for genetic screening; noninvasive prenatal testing (NIPT) can screen for trisomies 21, 18, and 13 using cell-free fetal DNA obtained from the maternal blood as early as 9 to 10 weeks of pregnancy; NIPT has a lower predictive value and more false-positive results in a general population vs in a higher risk population; conventional testing with first trimester screening (either integrated or other methods) or later second trimester quadruple screening is likely a better option in low-risk populations of women; NIPT is also not recommended for multiple gestation pregnancies; women with an elevated BMI also have a higher risk than others of having inadequate amounts of cell-free fetal DNA in blood collections; maternal alpha-fetoprotein can be drawn at 16 to 18 weeks in women who did first trimester screening or NIPT; a quadruple screen can be offered between 15 to 22 weeks and women who did not have prior genetic screening; any positive screening test should be followed up with a diagnostic ultrasonography and counseling about chorionic villi sampling in the first trimester or amniocentesis in the second trimester; an anatomy scan is done in most pregnancies in the United States around 18 to 20 weeks because this is when the organ systems can be best visualized while also performing a scan early enough to help confirm dating; a CBC, antibody screen for Rh-negative women, and glucose challenge or (glucola test) to screen for gestational diabetes are performed around 28 weeks; group B streptococcus testing is performed around 35 to 37 weeks and repeat STI screening should be considered at 36 weeks for those in increased risk of infection

Pregnancy Complications and Monitoring

Preeclampsia and gestational hypertension: hypertensive disorders affect 10% of pregnancies in the United States

Gestational hypertension: chronic hypertension begins prior to 20 weeks gestation and persists past 12 weeks postpartum; diagnosis requires a blood pressure of 140/90 mm Hg or higher on 2 occasions and blood pressure must be taken at least 4 hours apart; gestational hypertension involves elevated blood pressures that develop after 20 weeks gestation that are not associated with proteinuria or other criteria for preeclampsia; half of women diagnosed with gestational hypertension between 24 and 35 weeks gestation go on to develop preeclampsia during that pregnancy

Preeclampsia: involves systemic multisystem organ dysfunction characterized by hypertension and proteinuria; features plus new-onset hypertension after 20 weeks of pregnancy include thrombocytopenia, renal insufficiency, liver dysfunction, pulmonary edema, cerebrovascular dysfunction or stroke or visual changes; diagnosis of preeclampsia requires a systolic blood pressure of over 140 mm Hg or diastolic blood pressure greater than 90 mm Hg on 2 occasions at least 4 hours apart; plus, there must be either new onset-proteinuria or one of the severe features listed above; proteinuria is defined as at least 300 mgr protein in a 24-hour urine collection or a urinary protein-to-creatinine ratio of greater than or equal to 0.3; note that proteinuria is not necessary to diagnose preeclampsia if a severe feature is present; eclamptic seizures or eclampsia are often heralded by severe headache, visual disturbance, or hyperreflexia; half of patients develop seizures during the antepartum period; 20% of women have seizures while in labor and 30% of them have seizures only in the postpartum period; however, seizures can occur without other severe features of preeclampsia and in women who have normal blood pressure; magnesium sulfate helps prevent both eclamptic seizures and abruption in women with preeclampsia with severe features; in an otherwise asymptomatic woman with preeclampsia and a blood pressure less than 160/110 mm Hg without severe features, magnesium is not required unless severe features later go on to develop; low-dose aspirin is recommended beginning after the first trimester and in women with a history of preeclampsia; this recommendation has also been expanded to include multiple gestation pregnancy, type 1 or 2 diabetes, chronic hypertension, renal disease, autoimmune problems, and obesity; the treatment of preeclampsia with severe features or eclamptic seizures is delivery; with preeclampsia, without severe features as well as chronic, controlled gestational hypertension and chronic controlled hypertension, delivery is generally indicated at 37 weeks gestation, although earlier delivery should be considered if there are concerning maternal or fetal indications or worsening symptoms; because preeclampsia is a risk factor for future cardiovascular disease, identifying and managing cardiac risk factors following the delivery is a very good idea

Fetal heart rate monitoring guidelines: the National Institute of Child Health and Human Development Workshop report on electronic fetal monitoring released updated guidelines on fetal heart rate interpretation in 2008; for contractions, the terms hyperstimulation and hypercontractility have been replaced by tachysystole if there are >5 contractions in a 10-minute period averaged over a 30-minute strip; baseline fetal heart rate is also now rounded to 5-beat-per-minute increments over a 10-minute window and excluding any accelerations or decelerations; at least 2 minutes of identifiable baseline must be seen in order to establish a baseline or the tracing is called indeterminate; variability is now defined as either absent or the fetal heart rate amplitude is absent; minimal if the amplitude is there but below 5 beats per minute, moderate if the amplitude range is 6 to 25 beats per minute, and marked if the fetal heart rate amplitude around the baseline is greater than 25 beats per minute; if the fetal heart rate decreases from the baseline longer than 2 minutes but less than 10 minutes, this is now termed a prolonged deceleration; if this deceleration goes on to last longer than 10 minutes, that would be defined as a baseline change; sinusoidal fetal heart rate patterns are noted if the pattern persists for longer than 20 minutes; a 3-tier fetal heart rate interpretation method classifies categories as I, II, or III for each fetal rhythm strip; a category I tracing, considered normal, must have a baseline rated at least 110 to 160 beats per minute, moderate baseline variability, and no variable or late decelerations; there can be early decelerations and accelerations; these are strongly predictive of normal fetal acid-base status; category III tracings include either absent baseline fetal heart rate variability and recurrent later variable decelerations or bradycardia or a sinusoidal pattern; category III tracings are abnormal and suggest a compromised fetal acid-base status requiring immediate evaluation; category II tracings are between categories I and III

Shoulder dystocia: shoulder dystocia occurs when the anterior fetal shoulder wedges against the maternal pubic symphysis and impedes delivery of the rest of the body; incidence in the United States ranges from 0.4% to 1.4%

Risks: women with pre-existing or gestational diabetes have a higher risk; other intrapartum risk factors include history of prior shoulder dystocia, a history of prior infant over 4,000 grams in weight, maternal obesity, multiparity, and gestational age greater than or equal to 41 weeks; operative vaginal delivery with vacuum or forceps also increases risk, as do induction, epidural anesthesia, and fetal macrosomia

Management: after identification, a team is needed and the patient should be put in McRoberts position to increases the anteroposterior diameter of the maternal pelvis; if this does not work, suprapubic pressure is attempted through the maternal abdomen; McRoberts position with or without suprapubic pressure is thought to resolve approximately two-thirds of cases; there is not a great deal of data about what works best next; shoulder dystocia is generally unpredictable and the best outcomes are found when team management organized and communication good

Stillbirth: stillbirth is defined as delivery of a deceased infant after 20 weeks gestation; it affects 3.1 per 1000 pregnancies after 28 weeks gestation while rates between 20 and 27 weeks of gestation are around 3.2 in 1000 pregnancies in the United States; 30% to 50% of stillbirths are associated with fetal growth restriction (FGR), probably representing underlying placental dysfunction; one of the strongest risk factors is a history of prior stillbirth; other higher risk groups include women who are nullips with a history of prior fetal loss before 20 weeks gestation, women who have diabetes, women >40; and black women even with adequate prenatal care; the rate of perinatal death is consistent from around 24 weeks gestation to 39 weeks gestation and then it gradually increases in term and postterm periods; absolute risk of stillbirth, however, is still low from 39 to 41 weeks; although labor induction at 39 weeks is not thought to increase risk for caesarian delivery, universal induction at 39 weeks to prevent stillbirth is not recommended as general obstetric practice; although there is no certain way to prevent stillbirth, prepregnancy tobacco, and alcohol cessation, weight maintenance and management of glucose and blood pressure levels are suggested; note that women who first become pregnant >40 have an increased risk for stillbirth and other adverse outcomes compared with women >40 also pregnant but who have had an infant before age 40

Readings

Disclosures

For this activity, members of the faculty and planning committee reported nothing to disclose. In this lecture, Dr. Choby presents information that is related to the off-label or investigational use of a therapy, product, or device.

Acknowledgements

CME/CE INFO

Accreditation:

The Audio- Digest Foundation is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.

The Audio- Digest Foundation designates this enduring material for a maximum of 0 AMA PRA Category 1 Credits™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

Audio Digest Foundation is accredited as a provider of continuing nursing education by the American Nurses Credentialing Center's (ANCC's) Commission on Accreditation. Audio Digest Foundation designates this activity for 0 CE contact hours.

Lecture ID:

FMBR170136

Expiration:

This CME course qualifies for AMA PRA Category 1 Credits™ for 3 years from the date of publication.

Instructions:

To earn CME/CE credit for this course, you must complete all the following components in the order recommended: (1) Review introductory course content, including Educational Objectives and Faculty/Planner Disclosures; (2) Listen to the audio program and review accompanying learning materials; (3) Complete posttest (only after completing Step 2) and earn a passing score of at least 80%. Taking the course Pretest and completing the Evaluation Survey are strongly recommended (but not mandatory) components of completing this CME/CE course.

Estimated time to complete this CME/CE course:

Approximately 2x the length of the recorded lecture to account for time spent studying accompanying learning materials and completing tests.

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