Placental Problems in Pregnancy

Question 1

Define placentation

Answer 1

the formation or arrangement of a placenta or placentae in a woman’s uterus.

Question 2

What is hyperemesis gravidarum?

Answer 2

Severe nausea and vomiting which can cause electrolyte imbalance, weight loss and hospital admission

Question 3

What is the mechanism behind hyperemesis gravidarum?

Answer 3

bHCG may stimulate upper GI tract (as it’s structurally similar to TSH so can affect its receptors)

Question 4

How is hyperemesis gravidarum treated?

Answer 4

Thaimine, diet, IV fluids(no dextrose) and antiemetics

Question 5

How many pregnancies miscarry?

Answer 5

20-30%

Question 6

What are the different forms of miscarriage?

Answer 6

Threatened, inevitable, incomplete, complete, septic and missed

Question 7

What is a threatened miscarriage?

Answer 7

There is light and painless bleeding from the vagina, but the foetus is still alive. The cervical os is closed.

25% will go on to miscarry

Question 8

What is an inevitable miscarriage?

Answer 8

Bleeding is normally heavier and the foetus may be alive at this point, but the cervical os is open, and this is associated with pelvic cramps and is indicative that miscarriage is about to occur

Question 9

What is an incomplete miscarriage?

Answer 9

Where only some of the foetal parts have been passed. The cervical os is open and the vaginal bleeding continues

Question 10

What is a complete miscarriage?

Answer 10

All foetal tissues have been passed and the bleeding has diminished/stopped but the uterus is no longer enlarged and the os is CLOSED

Question 11

What is a septic miscarriage?

Answer 11

Contents of the uterus become infected and this causes endometritis where there is a tender uterus, fever may not be present and this condition may progress to a pelvic infection that causes abdominal pain and peritonism

Question 12

What is a missed miscarriage?

Answer 12

The foetus has not developed or has died in utero, and this is only recognised later when the bleeding occurs or on an USS (ultrasound scan). The uterus is smaller than would be expected for the dates. The cervical os is closed and the abdominal pain and vaginal bleeding are minimal.

Question 13

How are miscarriages managed?

Answer 13

Expected - wait and use syncytocinon or ergometrine if blood loss is large.

Foetal tissue may be removed using prostaglandins e.g. misoprostal

Question 14

What is recurrent miscarriage?

Answer 14

Three or more consecutive miscarriages

Question 15

What is the cause of recurrent miscarriages?

Answer 15

Autoimmune disease, chromosomal defects in the couple, hormonal factors, anatomical factors (cervical incompetence) or infection

Question 16

What is a molar pregnancy?

Answer 16

Also known as gestational trophoblastic disease. This is an abnormal pregnancy where a non-viable fertilised egg implants in the uterus and will fail to come to term

Question 17

Explain the pathophysiology of molar pregnancies

Answer 17

Trophoblastic tissue grows into a mass in the uterus with swollen chorionic villi. These villi then grow in clusters which resemble grapes

Question 18

How does a molar pregnancy arise?

Answer 18

Involves unviable fertilised eggs growing.

A complete mole involves two sets of paternal genes and no maternal genes which produces no foetus.

A partial mole involves 2 sets of paternal gene and 1 set of maternal which forms a non-viable foetus

Question 19

What are the symptoms of a molar pregnancy?

Answer 19

Light, torrential vaginal bleeding, hyperemesis gravidarum (due to excess hCG production) and passage of vesicles from vagina

Question 20

How does a molar pregnancy appear on ultrasound?

Answer 20

Has a snowstorm appearance

Question 21

What are the common causes of bleeding in late pregnancy (antepartum haemorrhage)?

Answer 21

Placental abruption or praevia

Question 22

What is placental abruption?

Answer 22

Painful vaginal bleeding from a normally-sited placenta

Question 23

What are the risk factors for placental abruption?

Answer 23

Multiparity, trauma, smoking

Question 24

What are the clinical signs of placental abruption?

Answer 24

Intense, constant abdominal pain (with or without vaginal bleeding, profound shock (DIC and oliguria), a tense and tender ‘woody’ uterus.

Foetal heart may be weak or absent

Question 25

What is the treatment for placental abruption?

Answer 25

If there is foetal distress before 37 weeks –> emergency C-section. If after 37 weeks labour, and no foetal distress, should be induced

Question 26

What is placenta praevia?

Answer 26

Where the placenta is inserted into the lower segment of the uterus after 24 weeks

Question 27

What is major placenta praevia?

Answer 27

Where the placenta covers the cervical os

Question 28

What is minor placenta praevia?

Answer 28

Where the placenta doesn’t cover the cervical os

Question 29

What is the clinical presentation of placenta praevia?

Answer 29

Painless vagina bleeding with soft and non-tender uterus

Question 30

Wha are the potential complications of placenta praevia?

Answer 30

Requirement for C-section due to canal obstruction, postpartum haemorrhage (as lower segment of uterus is less able to contract), placenta accrete (placenta implants in previous C-section scar –> may need hysterectomy)

Question 31

What is pre-eclampsia?

Answer 31

Abnormal maternal adaptation to the trophoblast leading to systemic hypertension

Question 32

How do you diagnose pre-eclampsia?

Answer 32

Protein in the urine and hypertension

Question 33

What are the signs of pre-eclampsia?

Answer 33

Hypertension, renal impairment, proteinuria, fluid retention, edema, weight gain and diffuse inseminated coagulopathy

Question 34

How is pre-eclampsia managed?

Answer 34

Monitoring and anti-hypertensives and anticonvulsants

Question 35

Describe twin to twin transfusions (TTTS) as a complication of multiple pregnancy

Answer 35

Occurs in monochorionic pregnancies where the one twin may take all of the nutrition