Pregnant and Nursing Patients Flashcards
Some precursors for secretion of hormones by the placenta come from the fetal adrenal cortex.
True or false?
True
Where is the site of fertilisation?
The oviduct in the fallopian tubes
How soon after ovulation must fertilisation occur? If this does not happen what are the consequences?
24 hours, if not, the ovum starts to disintegrate
What does the fertilised ovum differentiate into as it moves from site of fertilisation in oviduct to site of implantation in the uterus?
A blastocyst
What is the dense of mast cells grouped to one side of the wall of a blastocyst known as?
Inner cell mass
What is the thinner, outermost layer of the blastocyst known as?
Trophoblast
What is the function of the trophoblast?
Accomplishes implantation and develops into fetal portions of placenta
What group of cells is destined to develop into foetus?
Inner cell mass
What happens to the blastocyst when implantation is finished?
It completely buries into the endometrium
What three systems does the placenta perform all functions for the foetus?
Digestion, respiration, kidneys
What hormone is the basis of pregnancy diagnosis tests?
Human chorionic gonadotropin (hCG)
What is the source if oestrogen and progesterone during the first 10 weeks of pregnancy?
Corpus luteum
What peptide hormone causes contraction of the myoepithelial cells surrounding the alveoli of the breast?
Oxytocin
what happens to the uterus during involution?
Shrinks to its pregestational stage
Where is oxytocin formed and secreted from?
Formed in the hypothalamus and secreted from the posterior pituitary gland
By what process do substances such as oxygen, carbon dioxide, water and electrolytes cross the placenta?
Simple diffusion
By what process does a substance, for example, glucose, cross the placenta?
Facilitated diffusion
By what process does a substance, for example, amino acids, cross the placenta?
Secondary active transport
By what process does a substance, for example, cholesterol, cross the placenta?
Receptor mediated endocytosis
What organ does the placenta temporarily become during pregnancy?
Endocrine organ
what are the three endocrine systems during pregnancy that interact to support and enhance the growth/development of the foetus, coordinate timing of parturition, and prepare mammary glands for nourishing baby after birth?
- placental hormones
- maternal hormones
- fetal hormones
What are the most important hormones secreted by the placenta?
- Human chorionic gonadotropin (hCG)
- Oestrogen
- Progesterone
During pregnancy, what tissue would be described as transient?
Placenta
What is the function of human chorionic gonadotropin (hCG)?
To prolong the life-span if the corpus luteum
Where is human chorionic gonadotropin (hCG) eliminated?
In the urine
What happens to oestrogen and progesterone level as the placenta grows?
They rise
Why does the placenta not secrete oestrogen during the first trimester?
It does not have all the enzymes needed for oestrogen synthesis
When can the placenta secrete progesterone?
Soon after implantation occurs
Define what structures secrete oestrogen and progesterone through all 3 trimesters of pregnancy
1st trimester: corpus luteum
2nd trimester: placenta
3rd trimester: placenta
What are the two physiological roles of oestrogen?
- Stimulates growth of myometrium
- Promotes development of mammary gland ducts, through which milk will be ejected during lactation
What is the myometrium?
Uterine musculature
what are the three physiological roles of progesterone during pregnancy?
- Prevent miscarriage by suppressing contractions of the uterine myometrium
- Promotes formation of a mucus plug to prevent contaminants reaching foetus
- Stimulates development of milk glands in breasts
what are the two main functions of human chorionic gonadotropin during pregnancy?
- Maintains the corpus luteum
- Stimulates secretion of testosterone by the developing testes in XY embryos
What happens to the uterus during gestation?
It expands and increases in weight by more than 20x
What is parturition?
Labour, delivery or birth
what two factors are required for parturition?
- Dilation of the cervical canal
- Contractions of the uterine myometrium
What are Braxton-hicks contractions and when do they occur?
Mild contractions that are experienced with increasing strength and frequency, sometimes mistaken for onset of labour. They occur in the third trimester.
What peptide hormone, produced by corpus luteum and placenta, causes cervical softening during late gestation to prepare for parturition?
Relaxin
What three changes occur in the late stages of gestation to prepare for parturition?
- Braxton-Hicks contractions
- Softening of the cervix
- The foetus shifts downwards so that head is in contact with cervix
what is a breech birth?
Where any part of the body other than the head approaches the birth canal first
Once parturition has begun, what hormone has a positive feedback cycle which acts to increase uterine contractions?
Oxytocin
What happens during the first stage of labour?
Cervical dilation
What happens during the second stage of labour?
Delivery of the baby
What happens during the third stage of labour?
Delivery of the placenta
In the second stage of labour, what do stretch receptors in the vagina do?
Activate a neural reflex that triggers contraction of the abdominal wall in synchrony with the uterine contractions
How is the baby freed from the placenta after birth?
Cutting of the umbilical cord
After the third stage of labour, what happens in order to prevent haemorrhage?
Continued contractions of the myometrium constrict the uterine blood vessels at site of placental attachment
what is involution?
shrinking of the uterus back to it’s pregestational size
How long does involution take?
4-6 weeks
What two processes induce involution?
- A fall in oestrogen and progesterone when the placenta is lost at delivery
- By breastfeeding, Oxytocin promotes myometrium contractions that help maintain uterine muscle tone
What milk producing glands are lobules in breasts made up of?
Alveoli
How is milk ejected through the mammary ducts?
Contraction of surrounding myoepithelial cells
What hormones trigger development of the breast during pregnancy?
Oestrogen
progesterone
Prolactin
Human chorionic somatomammotropin (hCS)
What is the role of oestrogen in breast development?
Promotes extensive mammary duct development
What is the role of progesterone in breast development?
Stimulates abundant alveolar-lobular formation
What is the role of prolactin and human chorionic somatomammotrpin in breast development?
Induce the synthesis of enzymes needed for milk production
What hormones are produced when suckling triggers a neuroendocrine reflex?
- prolactin
- oxytocin
Upon suckling, what does prolactin stimulate?
Milk production
Upon suckling, what does oxytocin stimulate?
Milk ejection
What hormone causes contraction of myoepithelial cells?
Oxytocin
what is the milk produced in the first 5 days after delivery referred to as?
Colostrum
What is the importance of breastfeeding in the first 5 days after brith?
Colostrum contains concentrations of immunoprotective agents, important for the baby to receive.
What are the made nutrients that make up breast milk?
- water
- triglyceride
- lactose
- proteins
- vitamins
- calcium
- phosphate
What effect does lactation have on ovulation?
Tends to prevent it, decreasing the likelihood of another pregnancy
What three dental complications are pregnancy women at a higher risk of?
- increased caries and erosion risk
- increased periodontal disease risk
- increased tooth mobility due to disturbances in PDL attachment
What are teratogenic effects?
Effects of drugs on the formation of foetus
during what trimester is the foetus more prone to teratogenic effects?
First trimester
what position must pregnant patients NOT be placed in when receiving treatment in the 3rd trimester? And why?
Supine, because this would compress the maternal vena cava and aorta
What position should pregnant women in the 3rd trimester be placed in when receiving treatment?
On their left hand side, with their right hip slightly elevated
What is hypotension syndrome?
When the uterus compresses the inferior vena cava when a pregnant women is in supine position, leading to decreased venous return centrally
What two ways can mercury in amalgam cross the placenta?
Mercury vapour- passive diffusion
Methyl mercury- active transport by amino acid carriers
Should pregnant women receive an amalgam restoration upon treatment? Yes or no?
No
what are the concerns that have been raised about use of resin composites in pregnant women?
Concerns regarding elation of bisphenol A [BPA] in resin composites which may cross placental barrier
What is the first line antibiotic used to treat dental infections?
Pen V
What weeks does the first trimester cover?
Start of week 1 to end of week 12
Why does pregnancy gingivitis occur?
Hormonal changes make gums more susceptible to plaque, leading to inflammation and bleeding
What are the main hormones that arise and circulate during the first trimester?
Oestrogen, progesterone, hCG
Which weeks does the second trimester cover?
Start of week 13 to end of week 27
which trimester of pregnancy is the safest to treat the patient in?
Second trimester
What is the risk of performing sub-gingival PMPR on a pregnant patient?
There can be an ingress of bacteria into the bloodstream, increasing the likelihood of inflammatory response
Why does a pregnancy epulis occur?
Due to the high levels of progesterone that affects local vasculature, resulting in increased gingival exudate and swelling
If a pregnant patient has “pregnancy epulis” what would be your treatment plan going forward?
- Increase OH instruction
- Inform the patient not to worry as the epulis should regress post partum
What weeks does the third trimester cover?
Start of week 28 to week 40 (end of pregnancy)
In what trimester is ensuring the correct positioning of a pregnant patient in the dental chair most important?
Third trimester
Why should a new mother still be mindful of having amalgam fillings placed or removed?
Mercury in amalgam could still pass into breast milk if they are breastfeeding
How does pregnancy epulis appear clinically?
- red-purple swelling
- readily bleeds/ulcerates
What hormones reduce the thickness of the keratin in the gingival epithelium during pregnancy, rendering it a less effective barrier to bacteria?
Progesterone and oestrogen
If a pregnant patient presents with mild pregnancy gingivitis/epulis, what would your treatment plan be?
- OHI using TIPPS
- smoking cessation if applicable
If a pregnant patient presents with severe pregnancy gingivitis/epulis, what would your treatment plan be?
- OHI and smoking cessation
- debridement
- highlight to patient where supra-gingival deposits found
- may require more frequent recalls
What is pre-eclampsia?
Maternal high blood pressure
What are the three main adverse pregnancy outcomes of periodontal disease?
- Miscarriage
- Pre-eclampsia
- Preterm low birthweight
How could periodontal disease lead to pre-term labour?
Can cause the systemic levels of cytokines to rise (due to bacteraemia &/or by releasing pro-inflammatory cytokines into bloodstream), which could cause a premature increase in cytokine levels, reaching a threshold where labour is initiated early.
what medications should you never prescribe to a pregnant patient and why?
- aspirin (haemorrhage risk)
- tetracyclines (dental defects)
- prilocaine with fellypressin ( oxytocin effect)
- fluconazole (causes malformation of embryo)
- Miconazole (causes malformation of embryo)
- clarithromycin ( associated with fetal loss)
Which medication should specifically not be prescribed in the first trimester and why?
Clarithromycin, as it has been shown to cause fetal loss in animals
