11/4- Complications of Early Pregnancy Flashcards
How is gestational age determined?
- Full-term human pregnancy lasts 37-42 weeks (average is 40 weeks)
- Calculated from first day of last menstrual period (LMP)
- Developmental (conceptional) age is 2 weeks less than menstrual age
What are the time ranges for each trimester?
- First TM = 0-12 wks
- Second TM = 13-27 wks
- Third TM = 28-40 wks
What are the terms for pregnancy loss in terms of time frame?
- 0-20 wks = Abortion
- 20-36+6 wks = Preterm delivery
Case 1)
- Mrs. Adams comes to your office for her initial prenatal visit. - Her last menstrual period was 6 weeks ago, and she had a positive home pregnancy test 3 days ago.
- She has had one previous pregnancy which resulted in spontaneous miscarriage at approximately 7 weeks gestation.
- What is the likelihood of her current pregnancy resulting in a liveborn infant?
?
Define the following:
- Spontaneous abortion:
- Incomplete abortion:
- Threatened abortion:
- Missed abortion:
- Induced abortion (elective ab):
- Recurrent abortion:
- Incomplete abortion: retention of parts of products of conception
- Threatened abortion: patient presents with some vaginal bleeding, and the cervix is not dilated; abortion may or may not occur
- Vaginal bleeding in the 1st trimester is never considered normal but it does not necessarily mean morbidity
- Missed abortion: retention in the uterus of an abortus that had been dead for at least eight weeks
- Induced (elective) abortion: abortion brought on by medications or instruments
- Recurrent abortion: >3 spontaneous abortions
Fetal viability is only achieved in __% of all conceptions
- __-__% clinically diagnosed are lost in the 1st and 2nd TM
Fetal viability is only achieved in 30% of all conceptions
- 15-20% clinically diagnosed are lost in the 1st and 2nd TM
T/F: a spontaneous abortion may present with or without physical symptoms
True
When is the likelihood of spontaneous abortion lower?
Once fetal heart activity is visualized on USG
What are the recurrence risks of abortion if the woman has had prior abortions?
- With/without other liveborn children?
Another risk chart for spontaneous abortion
What are etiologies of spontaneous abortion?
- Chromosome abnormalities
- Abnormal morphology
- Placental mosaicism
- Luteal phase defects
- Metabolic disease
- Uterine anomalies
- Infection
- Other
What is the most common genotype involved in spontaneous abortion?
46,XX or 46, XY
What are the common chromosomal abnormalities responsible for spontaneous abortion?
- Normal 46,XX or 46, XY (54%)
- Monosomy X (45x) (9%)
- Tripoloidy (68, XXX or 69, XXY) (8%)
- Tetraploidy (3%)
- Structural abnormalities (2%)
- Autosomal trisomy (22%)
- Mosaic trisomy (1%)
What is the most common group of aneuploidy in spontaneous abortion?
Autosomal trisomies
Describe autosomal trisomies in terms of spontaneous abortion
- Prognosis
- Beneficial factors
- Most common one
- Caused by
- Most common group of aneuploidy in spontaneous abortion
- Most are lethal in early pregnancy
- Mosaics may have higher survival
- Single most common trisomy in spontaneous abortion: Trisomy 16
- 90-95% result of maternal non-disjunction
What is the single most common aneuploidy in abortuses?
45X
What causes 45X genotype (mostly)?
>80% are due to loss of paternal sex chromosome (no maternal effect!)
Look at this picture for confined placental mosaicism.
What are maternal diseases that may contribute to spontaneous abortion?
- Thyroid disease
- Diabetes (insulin-dependent)
- Chronic HTN (later losses)
- Collagen vascular diseases (e.g. Lupus)
What are uterine factors that may contribute to spontaneous abortion?
- Intrauterine synechiae (adhesions)
- Mullerian anomalies
- Bicornate or T shaped uterus, etc.
- Fibroids (benign, large masses within the uterus
- Incompetent cervix
What are common exposures that may contribute to spontaneous abortion?
- Radiation (way higher SAb if > 10 rads)
- Smoking (increased SAb if moderate/more)
- Alcohol ( but teratogenic)
- Caffeine ( if moderate)
- Trauma (unlikely)
What are the different management methods of spontaneous abortion?
- Expectant
- Medical
- Surgical
Case 2)
- Miss Burke, a 22 year old college student, presents to the ER with severe LLQ pain. The pain has been getting steadily worse over the past 10 days.
- She thinks she started her period a couple days ago.
- She states she “likes to party”, is sexually active, and not using contraception. Her pregnancy test is positive.
- During the evaluation, she becomes tachycardic and hypotensive.
- What is the most likely diagnosis?
Ectopic pregnancy
What is an ectopic pregnancy?
Any pregnancy implanted outside of endometrial cavity
What are common sites of ectopic pregnancy?
- Tubal (96%)
- Ampullary (most common)
- Isthmus (2nd most common)
- Interstitial, cornual (rare, 2-5%)
- Ovary (0.5-1%)
- Fimbria (very rare)
- Cervix (0.1%): very rare but very dangerous
Look at this picture of a tubal pregnancy.
This camera is coming from the anterior abdominal wall
T/F: the incidence of ectopic pregnancies is increasing?
True
What are contributing factors to ectopic pregnancies?
- More conservative PID therapies (rather than surgical excision)
- Successful tubal surgeries
- Increased use of assisted reproduction, such as IVF
What are risk factors for ectopic pregnancy?
- Previous pelvic infection
- Previous tubal surgery
- Intrauterine device in place
- Previous tubal pregnancy
What is the clinical presentation of an ectopic pregnancy?
- Abdominal pain (90-100%)
- Amenorrhea (75-85%)
- Vaginal bleeding (50-80%)
- Dizziness
- Pregnancy symptoms
- Tissue passed
What are physical findings with an ectopic pregnancy?
- Adnexal tenderness (75-90%)
- Abdominal tenderness (80-95%)
- Adnexal mass (50%)
- Uterine enlargement
- Orthostatic bp changes
- Fever
How is an ectopic pregnancy diagnosed?
- Monitor hCG levels (normally doubles every 48 hrs in the 1st TM)
- High-resolution ultrasonography
How should an ectopic pregnancy be managed?
- Vaginal ultrasonography to look for intrauterine gestational sac
- If intrauterine gestation sac visualized: routine follow up (repeat US in 1 wk)
- If no intrauterine gestational sac seen: look for tubal pregnancy
- When looking for tubal pregnancy, if none visualized, do quantitative hCG (if > 2000 than treat for ectopic pregnancy, otherwise follow up)
- If tubal pregnancy visualized, treat for ectopic pregnancy
What are treatment options for ectopic pregnancy?
Surgical
- Laparoscopy with salpingectomy or salpingotomy
Medical
- Methotrexate (single or mutliple dose); recall, this inhibits DHFR (stop prenatal vitamins with folate)
Case 3)
- Mrs. Chang, a 42 year old librarian, presents to the Emergency Room with heavy vaginal bleeding and passage of tissue she describes as “lots of tiny sacs”.
- Her menstrual periods are irregular, and the last one was 4 months ago.
- On physical exam, her uterus reaches to the level of her umbilicus.
- What is your next step in her evaluation and treatment?
Molar pregnancy (hydatidiform mole)
What is a molar pregnancy (hydatidiform mole)?
- Definition: abnormal development of chorionic villi in pregnancy (with or without fetal tissue)
- Can persist and develop into gestational trophoblastic disease (GTD)
What are features of molar pregnancy?
Features of complete mole:
- Trophoblastic proliferation
- Cystic villi
- No fetal tissue
What is a partial mole?
- Fetus or fetal tissue present
- Non-viable: multiple structural anomalies of fetus with major growth lag
What is the clinical presentation for a molar pregnancy?
- Vaginal bleeding
- Uterine size discrepant from dates
- Hypertension
- Hyperemesis
- Thyroid dysfunction
- Theca lutein cysts of ovaries
What is seen here?
Ultrasonographic findings of a molar pregnancy:
- Left: 11 wk fetus
- Right: hydatidiform mole
What groups are most affected by molar pregnancies?
Asian
- Vietnamese
- Japanese
American…
What are risk factors for molar pregnancy?
- Maternal age < 20 or > 40 yo
- Asian ethnicity
- Prior molar pregnancy
- Low SES (possible nutritional factors)
Look at this flowchart for therapy of molar pregnancies
