Obstetrics Flashcards
(27 cards)
What is the role of progesterone in early pregnancy compared to later pregnancy?
Early pregnancy - induces endometrial secretary changes favourable for blastocyst implantation
Later pregnancy - induce immune tolerance for the pregnancy and prevent myometrial contractions
What are the three forms of oestrogen and how are they converted?
Estradiol - non-pregnant reproductive - converted from androgens produced from cholesterol in the follicular theca cells by aromatase enzyme in the follicular granulosa cells
Estriol - during pregnancy - converted from dehydroepiandrosterone-sulfate from the fatal gland by sulfatase enzyme in the placenta
Estrone - menopause - from adrenal androstenedione by peripheral adipose tissue
What is Chadwick’s sign?
Bluish or purplish discolouration of the vagina and cervix caused by increased skin vascularity in pregnancy
What are the in utero shunts within the foetus?
Ductus venosus - carries blood from umbilical vein to the inferior vena cava
Foramen oval - carries blood from right to left atrium
Ductus arterioles - shunts blood from pulmonary artery to defending aorta
What arises from the ectoderm?
CNS, PNS, sensory organs of seeing and hearing, integument layers (skin, nails, hair)
What arises from the mesoderm?
muscles, cartilage, CVS, urogenital system
What arises from the endoderm?
lining of GI and respiratory tracts
What are the effects of alcohol on the growing fetus?
fetal alcohol syndrome - IUGR, mid facial hypoplasia, development delay, short palpebral fissures, long philtrum, multiple joint anomalies, cardiac defects
What are the effects of diethylstilbestrol on the growing fetus?
DES syndrome - T shaped uterus, vaginal adenosis (with predisposition to vaginal clear cell carcinoma, cervical hood, incompetent cervix, preterm delivery
What are the effects of dilantin on the growing fetus?
fetal hydantoin syndrome - IUGR, craniofacial dysmorphism (epicanthal folds, depressed nasal bridge, oral clefts), intellectual disability, microcephaly, nail hypoplasia, heart defects
What are the effects of isotretinoin on the growing fetus?
congential deafness, microtia, CNS defects, congenital heart defects
What are the effects of lithium on the growing fetus?
Ebstein’s anomaly (right heart defect)
What are the effects of tetracycline on the growing fetus?
after fourth month, deciduous teeth discolouration
What are the effects of thalidomide on the growing fetus?
phocomelia, lim reduction defects, ear/nasal anomalies, cardiac defects, pyloric or duodenal stenosis
What are the effects of trimethadione on the growing fetus?
facial dysmorphism (short upturned nose, slanted eyebrows), cardiac defects, IUGR, intellectual disability
What are the effects of valproic acid on the growing fetus?
neural tube defects (spina bifida), cleft lip, renal defects
What are the effects of warfarin on the growing fetus?
chondrodysplasia (stippled epiphysis), microcephaly, intellectual disability, optic atrophy
What are the effects of streptomycin on the growing fetus?
VIII nerve damange, hearing loss
What are the criteria for the use of methotrexate in an unruptured ectopic pregnancy?
Pregnancy mass <3.5cm diameter
Abcense of fetal heart motion
B-hCG <6 000 mIU
No history of folic supplementation
Why are nonsteroidal anti-inflammatory drugs not recommended during pregnancy?
An increased risk of oligohydramnios. Nonsteroidal anti-inflammatory drugs have been shown to increase the risk of spontaneous abortion if taken at the time of conception or for more than 7 consecutive days during the first trimester
What is the recommended dose of folic acid for women at high risk for fetuses with neural tube defects?
4mg
What is the recommended dose of folic acid for women if no increased risk for neural tube defects exists?
0.4mg
What is the recommended dose of folic acid for women with twin pregnancy?
1mg
What is the most common cause of ectopic pregnancy?
Previous infection with gonorrhea or chlamydia, resulting in PID
