Pathophysiology – Alterations in Reproduction
- HPO Axis: Hypothalamic pituitary ovarian axis, the main hormonal feedback pathway
responsible for the reproductive system
- Menarche: the first menstrual cycle achieved
- Os: The opening from the uterus through the cervix into the vagina, can measure the dilation
of the os to monitor the progress of labour.
- Fondus: the top of the uterus, during pregnancy this can be used as one measurement point
for monitoring growth of the fetus (symphysis‐fundal height), after delivery the fondus is
palpated to monitor the resolution phase.
- Infertility: failure to achieve pregnancy after one year of unprotected intercourse, nothing
that if the female partner is over 35 years then the interval is shortened to 6 months.
- IUI: Intra uterine insemination, where a small catheter is passed into the uterus via the vagina
and cervix so that the semen may be instilled directly into the uterus.
- IVF: In vitro fertilization, the process by which the ova and semen are collected from the
individuals and mixed together to permit fertilization to occur and after 3‐5 days later 1‐2
growing embryos are returned to the uterus, any remaining fertilized ova can be frozen for
- Prenatal: The period of time from conception to the birth of the infant, also known more
commonly within the health care community as the antenatal period.
- Postnatal: The period of time from the delivery of the infant until complete resolution of the
body to pre‐pregnant state, usually 6‐8 weeks.
- Parity: The number of deliveries that a woman has had over 20 weeks gestation, when this
number is over 5 this is considered to be a state of grand multiparity, or the woman is referred
to as a grand multipara.
- GTPAL: A short hand describing a woman’s obstetrical history.
G= gravida, or total number of pregnancies, including miscarriages, abortions and stillbirths.
T= term, the total number of deliveries over 37 weeks gestational age
P= preterm, the total number of deliveries between 20‐37 weeks gestational age
A=abortions, which can be spontaneous (occurring on their own) or therapeutic (occurring by
L= the number of living children
- Viability: the point at which should a fetus deliver there is a reasonable expectation of
survival, usually defined as 500 gm or more than 20 weeks gestation. This is a contentious
issue and will not be further discussed in this forum.
Macrosomia: When the fetal head size has grown larger than can be passed vaginally
Polyhydramnios: The amount of amniotic fluid is more than 2 standard deviations above the
norm for gestational age. 2
Normal Female Anatomy
‐ Remembering the sexual differentiation of an embryo occurs around the 7 week of
- It is determined by the sex chromosomes. XX for female and XY for male
- The SRY protein on the male or Y chromosome is the testes determining factor.
- And females, without exposure to this protein will develop the vagina, uterus and fallopian
tubes. Otherwise known as ovarian ducts.
- The ovaries produce the secondary eugocytes and hormomes such a estrogen, progesterone,
inhibine and relaxin
- At birth the ovaries of the female newborn contain all their primary eugocytes and their
secondary eugocytes are formed after puberty once a month at ovulation
- The uterine tubes or fallopian tubes transport the secondary eugocyte to the uterus. And
normally these tubes are the sites (remember the left or right) where fertilization occurs.
- The uterus is the site of implantation for the fertilized ovum, this muscular organ is where the
fetus will develop during pregnancy. And will promote the progression of labour. (review the
layers: endometrium, myometrium and perimentrium)
- The vagina is the receptacle for sperm during intercourse and also the pathway for childbirth. 3
- The position of the uterus in the pelvis is something females are born with. And this uterine
position will remain the same throughout their lifetime.
- During a routine pelvic examination, the clinician can palpate the uterus during a bimanual
examination to determine their uterine lie or position (as shown in diagram). This does not
- With the onset of puberty, the hypothalamic neurosecretory cells release the ganadortropin
releasing hormone (GnRH), which subsequently binds to the anterior pituitary cells called the
gonadatropes and stimulates then increase the secretion of the follicular stimulating hormone
(FSH) and lutenizing hormone (LH)
- FSH stimulates the growing follicles of the ovary to produce estrogen, progesterone, and
- LH is responsible for stimulating the ovulation. Remembering the LH serge in the formation of
- Estrogen is responsible for the development and maintenance of the female reproductive
structures, secondary female characteristics, such as adipose tissue deposition, voice pitch,
broad pelvis, and pattern of hair growth. As estrogen can work synergistically with the human
growth hormone, it can increase protein synthesis, including bones. Lastly, estrogen lowers
blood cholesterol, although the exact mechanism for that is unknown
- Progesterone is secreted mainly by the cells of the corpus luteum in the last 2 weeks of the
mestrual cycle. It works with estrogen to prepare and maintain the endometrium and to
prepare the mammary glands for lactation.
- Relaxin is produced by the corpus luteum and it has a role to play with the relaxation of the
uterine smooth muscle.
- Inhibin is secreted by the granulosa cells of the follicles, and together with the levels of
estrogen and progesterone, these hormones provide feedback for this HPO axis, either
stimulating or inhibiting further release of FSH and LH
Female Monthly Cycle Summary 4
assume the cycle is 28 days, the normal female reproductive cycle can range from 24‐36 days.
With the biggest variation occurring during the preovulatory phase.
‐ Day 1‐5 is the menstrual phase where the uterus sheds all that the
deepest layer of the endometrium, approximately 50‐150 mls of blood, tissue, fluid, mucous,
epithelial cells. This discharge is due to the decreased amount of progesterone and estrogen.
‐ Clinically we can manipulate this with endogenous hormones. Such as
the oral birth control pill.
‐ So when the woman stops taking the active hormone, the level of
progesterone particularly decreases and this withdrawal promotes the bleeding
‐ At this time, the ovarian hormones are at the lowest levels and this
stimulates the secretion of GnRH and subsequently FSH, LH
‐ Day 6‐14 is the variable preovulatory phase and under the influence of
FSH, the maturation of the dominant follicle occurs. This phase is the proliferative phase for
the uterus as estrogen promotes the endometrial growth
‐ At approx. day 14, ovulation occurs when the secondary eugocyte is
released into the pelvic cavity, surrounded by the zona polusida and corona radiada
‐ The leftover cells in the ovary become the corpus luteum under the
influence of LH. And this structure then secretes estrogen, progesterone, inhibin and relaxin
‐ Day 15‐ 28 is the post ovulatory phase during which the progesterone
and estrogen secreted by the corpus luteum causes further growth and coiling of the
endometrial glands 5
‐ And thickening of the endometrium, all in preparation for fertilized
ovum. Without a fertilized ovum, the corpus luteum degenerates leading to decreased
amount of progesterone. With the withdrawal of progesterone menstruation occurs.
the terminology for human embryology. The fertilized ovum is called a zygote. Up to 2 weeks
this collection of rapidly proliferating cells is called the blasticytes. From 2‐8 weeks, an embryo.
And from 8 weeks – birth its called a fetus.
‐ To achieve pregnancy, the fertilized zygote eeds to be able to penetrate into endometrium
layer of the uterus. This process takes several days
‐ At about day 10‐12 post fertilization, you will start to see rise in the beta subunit of the glycol
protein called the human corionic gonadatrope hormone or HCG.
‐ This is the marker used to detect pregnancy both in urine and blood within a few hours after
implantation the trophoblasts or specialized cells around the blasocytes will begin to produce
‐ HCG specifically produced during pregnancy. The role of this hormone is to maintain the corpus
luteum, which produces the increasing amount of progesterone needed to support and thicken
the uterine lining.
‐ If the HCG levels are insufficient, the corpus luteum will regress, progesterone levels will drop
and the sloughing of the endometrial layer will occur. 6
‐ Tyically the beta HCG value will double every 2 days in early pregnancy. And clinically this fact is
used to support liability of the pregnancy or to rule out ectopic pregnancy.
‐ A blood test is a more sensitive test that can detect a rise about 5 international units per litre.
And for a urine test to be positive, the hormone must be at the level of 25 international units
‐ When doing a home pregnancy test, it is best to use the first void of the morning as this level of
the hormone will be the most concentrated.
‐ With respect to implantation, some women will experience some spotting or light bleeding at
the time that their next menses is due. However, it will be much lighter than their usual flow.
This can signify, potential implantation bleed caused by the growing of the zygote through the
endometrial layers. It is usually not of consequence but can falsely date a pregnancy when a
woman feels she did have menses at her normal expected time.
‐ The development of the placenta and fetus is continuous process that begins at the time of
‐ Embryogenesis is a stage of rapid development of the ectodermal, endodermal, and mesodermal
layers for all the structures and systems in the human embryo and fetus.
‐ By the end of the 13 t week of gestation all major structures and pathways are formed and the
remainder of the pregnancy is more about growth and fine tuning of these. This is why the first
trimester is the most important in trying to assure that the baby will be born healthy.
‐ However, due to the fact that most pregnancies are still unplanned, it is at this time the
developing fetus can be exposed to adverse substances and events, such as alcohol ingestion,
tobacco, smoking, and use of recreational drugs. 7
‐ The chorion membrane is derived from 2 layers of tissue. The inner layer from the ectoderm that
becomes the trophoblast, the outer which is the mesoderm.
‐ The trophoblast divides rapidly and creates small finger‐like projections into the uterine
myometrium to begin to form the chrionic villi.
‐ The mesoderm fills in these projections with branches of umbilical vessels, so that they become
‐ The chorion contributes to the development of the placenta, especially those parts of the chorion
that are in contact with the uterine wall. Between 8‐10 weeks the placenta will develop and take
over the task of producing progesterone and HCG enabling the corpus luteum to degenerate.
‐ At 10‐14 weeks the chorionic villi and introvelius spaces for maternal sinuses has blood flowing
and can facilitate gas and nutrient exchange.
‐ Oxygen plays a key role in the regulation of the ovilius vascularogensis.
‐ At this time there is increased blood flow, increased intraplacental oxygen demand and increased
oxygen tension that may contribute to excessive oxadive stress which can be overwhelming in
some pregnancies and can lead to miscarriage.
‐ Ultimately the arteries and veins increase in number and capacity and divide into secondary, then
tertiary vessels before entering the main stem villi or umbilical stock
‐ The placenta is a phenomenal organ and is the provider of all fetal nutrition during the
‐ It is formed by the 10 week of gestation, it acts to filter nutrients, oxygen and fetal waste
products by diffusion between the mom and the fetus.
‐ The palcenta forms finer‐like projections or interdigitations into the endometrium that perform
these important functions. 8
‐ After delivery of the baby, a woman will experience locia flow. This is a sign that the location of
the placenta attachment is healing. Think of it as an open wound, after separation from the
placenta and that heals like a scab would on your arm.
‐ The amnion is a membranous sac that surrounds the developing fetus and provides protection as
the fetus grows. It appears as a small sac that eventually enlarges and becomes fluid filled by the
forth or 5 week. The amniotic fluid or likewar continues to accumulate to be a total of about 1‐2
litres at term. When the water breaks, it is an opening of the amniotic sac that permits the fluid to
‐ When the membranes rupture, we note the quantity, and colour of the fluid to determine if the
fetus has passed maconium prior to birth, as this does change delivery protocol. As this is an
institution specific decision, it will not be discussed further here.
‐ In certain conditions of pregnancy, the amnion can produce too much or too little amniotic fluid
‐ Polyhydromnius is associated with gestational diabetes and involves an excessive amount of fluid
which can overdistem the uterine cavity and lead to poor discend of the presenting part into the
‐ Should the membranes rupture prior to adequate descent, then there is a potential for the
prolapse of the umbilical cord which is an obstetrical emergency.
‐ Think about the usual symptoms of diabetes, increased thirst and urination, and that can help you
think about too much fluid in this instance.
‐ Gestational hypertension can also be associated with olygoat hydeminous or too little fluid
around the baby. This can lead to intolerance of the stresses of labour such as fetal heart
decelerations. Again, think of what happens with high BP, the vessels are constricted and thus not
as much blood passes between the placenta and the fetus and results in lower volume of fluid.
‐ 2 umbilical ateries and 1 umbilical vein.
‐ The umbilical veins carry oxygenated blood to the fetus
‐ Th artery removes deoxygenated blood
‐ Think back to the only other clinical example of this which is the pulmonary vasculature. The
pulmonary arteries carry deoxygenated blood to the lung and the puolmoary veins return the
oxygenated blood to the heart.
‐ The pulmonary placental vessels are the only anatomical examples of where this inversion exists.
‐ The delivery of the placenta is the 3 r stage of labour, the cord is always inspected after delivery
for the presence of the 3 vessels often on routine ultrasound of any pregnancy they will also look
for the 3 vessels of the cord.
‐ The delivery midwife or delivering physican will always examine the placenta following the
delivery to ensure that the placenta is whole and that there are no gross abnormalities.
‐ There could be a valamentous or circumvlate cord insertion, vasa previa or a succesnturiate, aka
accessory lobe of the placenta,
‐ If the baby is small for gestational dates, meaning less than 2500 grams at full term birth, post
dates, that is born after 41 completed weeks of gestation or the placenta did not appear normal
upon close examination, It can be sent to pathology for histological studies. 9
‐ Placental abnormalities:Valamentous: insertion of the umbilical cord in which the major umbilical
vessels separate in the fetal membranes before reaching the placental disk. Such a condition is of
no major consequence in utero, but could lead to a greater chance for cord trauma with bleeding
‐ Placental abnormality: Vasa Previa : placenta after delivery showing vasa previa. Vessels are seen
running unprotected through the membranes
‐ Placental abnormality: Placenta accrete: results from a lack of formation of a normal decidual
plate. The decidual plate is the normal cellular boundary of the maternal side of the placenta and
the uterus, which usually doesn’t extend past the endometrium. With placenta accrete the
chrionic villi abnormally extend into the myometrium, and the placenta cannot separate normally
following delivery and severe hemorrhage results.
‐ The location of where the
happens by chance.
However there are some
risk factors for the
development of placenta
previa which includes
recurrent abortions or miscarriages, or uterine surgery.
‐ Placenta previa is a condition where the placenta forms so that is either completely or partially
covering the uterine os.
‐ During routine antenatal ultrasound the position of the placenta in the uterus is always
commented on. This ultrasound is done at 18‐20 weeks gestational age.
‐ If there is a finding of abnormal placentation, it will measure how close the leading edge of the
placenta is to the uterine os, which is the opening of the uterus to the cervix
‐ This provides a guide to the clinician about option delivery. Theres a potential that the placental
location can change as the uterus continues to grow during the pregnancy. And so, repeat
ultrasound examination will be undertaken
‐ Should the palcenta completely cover the os, the delivery will be planned by c‐section. With a low
lying or marginal previa they may consider a vaginal birth but usually with a double set up. That is
being prepared to perform a c‐section a moments notice
‐ The big risk with this condition is an antipartum hemorrhage which can put both mother and
baby at risk. So with this diagnosis, comes a recommendation for complete pelvic rest 10
Hormones in pregnancy
ormone panel change in pregnancy
‐ The most important being the rise in estrogen and progesterone and the appearance of the
human chorionic gonadatropins and placental proteins
‐ The Beta HCG is one example of chorionic gonadotropins that we have discussed, as this is initially
created by the trophoblasts and its main role is to maintain the corpus luteum in pregnancy.
‐ Also HCG has the capacity with its thyroid stimulating hormone‐like activity (TSH‐like activity) to
stimulate the maternal thyroid gland to increase circulating thyroid hormones
‐ Maternal thyroidin crosses the placenta and facilitates fetal development and in some studies,
maternal thyroid dysfunction can be associated with an increase risk of preaclamsia, gestational
hypertension, low birth rate, pre‐term delivery, perinatal morbidity and mortality
‐ Other chorionic gonadotropins include HCS (Human chorionic somatomotropin) and HCC (human
chorionic corticotrophin )
‐ hCS is a protein hormone with immunological and biological similairities to the pituitary growth
hormone and in some literature it is called the human placental lactogen.
‐ hCS is referred to as growth hormone of pregnancy. With anti‐insulin characteristics, namely
decreased glucose uptake and increase free fatty acids being released
‐ It also has potent prolactin‐like or lactinogenic bioactivity. It is secreted by the placenta into the
maternal circulation with very little reaching the fetal circulation. The maternal plasma
concentrations are linked to placental mass, new research is looking at the functions of this
hormone with fetal growth.
‐ Human Chorionic Corticotropin (hCC), this role is unclear, but interestingly the levels of hCC can
be detected in both maternal and fetal circulations. But the maternal hCTH doesn’t reach the 11
fetus. And the thinking is that the placental HCC is not under the feedback regulations by
‐ A number of pregnancy proteins have been identified such as the pregnancy associated plasma
proteins (ex. PAPP‐A, which is used for down syndrome screening)
‐ There are also macroglobulines, placental proteins, placental membrane proteins and although
these have been isolated, their functions have yet to be fully known
‐ The corticotrophin‐releasing hormone is another placental synthesize hormone which is different
‐ Placental CRh has similar characteristics of the hypothalamic CRh. (please review the stress
response module for more information)
‐ CRh is a non‐pregnant woman is appromixately 5‐10 picamoles/litre. But during perganncy, this
icnraeses to 100 early in the third trimester and 500 picamoles/litre in the last 5‐6 weeks of
‐ With the onset of labour, this level can rise another 2‐3 fold
‐ Much of its role and resgulation are unknown, but it has been postulated that it plays a major role
in the timing of partuition, with the increase levels of CRh at the end of pregnancy the smooth
muscle relaxing and there is an increase formation of protaglandins.
‐ The other role that is associated with this is the fetal lung maturation and the development of
‐ Cortisol signals the lungs to start producing surfactant so that the lungs may in turn turn into
functioning tissue upon delivery
‐ In the fetal state the lungs do not function in the manner that they do once in extra‐uterine life.
While the organ develops and it grows it doesn’t function in utero to provide oxygenated blood to
‐ Of threatened with premature labour ensues then a medication called Selestone or
betamethazone, a corticosteroid will be usually given in 2 doses, 12‐24 hrs apart by IM injection.
This is to mimic the effects of the natural cortisol and promote maturation of the fetal lungs.
‐ Placental progesterone is essential to maintain the pregnancy. Especially the uterine linings.
‐ Esptrogen is primarily formed from DHA which is secreted by zona reticularis layer of the adrenal
cortex of both mom but in much larger quantities by the fetus and is transported to the placenta
where it is converted to estradial, estrone and estrial
‐ Estrogen causes enlargement of the uterus, breast ductle structure and the pregnant womans
‐ Estrogen also works with relaxin to relax the pelvic ligaments namely the limphesis puvisis
becomes elastic to allow easier passage of the fetus during delivery. Not that you would every
elude to the fact that a woman in later stages of pregnancy would walk funny or wattle but the
relaxed pelvic gurdle promotes this gate
Hormones in Pregnancy continued 12
‐ Human chorionic gonadotropin has
2 major subunits = alpha and beta
‐ Remember it’s this glycoprotein that
is responsible for maintaining the
corpous luteum of pregnancy.
‐ It is the beta subunit that’s
measured with pregnancy tests of
blood and urine
‐ Alpha hCG is used in fertility
treatments to promote ovulation
‐ In 2011, alpha hCG was in the news
on a talk showing, discussing this as
a diet aid for weight loss. The
evidence to support the use of this
hormone to support weight loss is
‐ During pregnancy, the levels of
estrogen and progesterone continue to rise . This is to support the changes in the breast tissue to
permit breastfeeding and to keep the endometrium lining thick and plentiful to support the uteral
Changes in Pregnancy
‐ At 12 weeks gestation, you will just begin to palpate the uterus of a pubic bone, while doing a
‐ It is at this time that you may be able to ascultate the fetal heart beat with a ultrasound dopler
using the appropriate transmission gel.
‐ The uterus will be the shape of a large avocado or the size of a soft‐ball. 13
‐ At 16 weeks the fondues of the uterus will be of about half way between the pubic bone and the
‐ At 20 weeks, the fundus should be around the umbilicus. At this time you would start to measure
the symphysis fundal height, which is a quick clinical measure of fetal growth.
‐ With a singlon pregnancy you would expect the FSH to be within 1‐2 cm of the number of weeks
‐ Note that an infant born before 37 is considered a pre‐term infant. If born between 37 and 42
weeks the infant is term. And if born after 42 weeks it is considered post‐term.
‐ Weight Gain: it is a common misconception that when a woman is pregnant, she is eating for 2.
Remember that in the early stages of pregnancy, the second individual is smaller than a pea so
while the nutrient needs increase, the caloric needs are not significantly greater. Excessive weight
gain during pregnancy can put the woman and fetus at risk. Conditions such as gestational
diabetes, gestational hypertension ,fetal marcosomia, and distosia labour can occur. Distosia
labour is where the uterus cannot get into a concerted rhythmic pattern of contractions to affect
delivery. Usually the labour can be augmented if this occurs.
‐ Uterine sizes:
‐ Dating for EDC: When calculating the due date or expected date of confinement or EDC, it is
imperative to use and determine the first day of the last normal menstrual cycle (LMP). Be aware
that the interval from the last menses ovulation is included in the EDC calculation. Many ppl date
in their minds from the intercourse date but this is incorrect and can lead to confusion and upset
when a date is jive when a partner is in town. Once an EDC has been established, and confirmed
with an ultrasound, it is very important that you do not change it be consistent. Many women
come out of their antenatal appointments saying they have no idea when the baby is due, ppl say
diff dates. It is not a nursing responsibility to change a due date. You can also use a pregnancy
wheel which is the easy way to determine the date. Line up the arrow for LMP day and follow
around the circle until you come to the EDC day. Make sure you use a consistent wheel because
there are some minor differences in manufacturers if unable to access an actual wheel, you can 14
make your own with the link in slide. Another way to calculate the date is to use a pregnancy
calculator. There are many websites that simplify, they require you to put in the LMP day and
they’ll provide an EDC based on the information. There are also apps, some even free or this
feature. The least frequently used method is the Naegele’s Rule. Which is to subtract 3 months
and add 7 days to your first day of the LMP date.
Full Term Pregnancy
‐ At the time of delivery we do try to evaluate the presenting position of the fetus in the pelvis. This
is done by palpating for either the anterior or the posterior frontanals of the infant during a
‐ The anterior frontanal is a diamond shaped soft spot created where the skull bone comes
together. The posterior frontanal is triangular shaped.
‐ The purpose of determining the frontanals is to determine which way the oxyput, back of the
skull is pointing. Oxyput anterior presents the fetus in the best position to effect a vaginal
delivery. As the widest part of the head goes into the widest part of the pelvis.
‐ Conversly, oxyput transverse in posterior presentations put the wide part of the head into the
narrow part of the pelvis and this can result in failure to progress or to descend.
Key changes that occur during pregnancy:
‐ Uterus: It enlarges from a 50 g size to 1100 gm and the volume increases from 10 ml to hold an
average of 5000 mls or 5 L and in some extreme cases up to 20 L. The uterus is initially the shape
of a pear becomes more spherical by 12 weeks. And then an oval shape with an increase in length
compared to width for the rest of the pregnancy. The uterus starts in the pelvic cavity but after 12
weeks rises towards the anterior abdominal wall and ultimately the liver and starts to displace the
intestines laterally and superiorly. As the pregnancy progresses, the hypertrophic uterus becomes
more elastic and fibrous in response to estrogen and progesterone levels. The position of the
placenta influences where the uterus becomes more hypertrophic because the area of the 15
placenta site enlarges more rapidly than the rest. Also the uterine isthmus becomes soft and
compressible known as Hegar’s sign.
‐ Breast: Nipple enlargement and increased pigmentation occurs during pregnancy. With an
increased blood supply, the veins become more visible & in the second and third trimester the
proliferation of the mammary glands occur related to the pregnancy hormones. More
pronounced elevations noted on the areoli are hypertrophic savatious glands called the glands of
Montgomery or Montgomery’s tubercles. The mammary glands are ready for lactation during
pregnancy however this is prevented with high levels of estogen. So after delivery, when the
estrogen levels drop, lactation can occur. Also one side note, despite popular misconceptions the
pre‐pregnant breast size and the post delivery milk production do not correlate.
‐ CV: As the uterus enlarges, and pushed against the diaphragm the heart becomes laterally
displaced to the left which directly impacts the PMI landmark. Overall, the heart size increases
both in intracardiac volume and myocardial mass, by approx. 12% to accommodate the demands.
The mother’s cardiac output increase 30‐40% peaks around 24 weeks. Blood volume increases
40‐50% during pregnancy and this hypervolemia helps meet the metabolic demands of the
placenta and enlarging uterus. While the blood volume increases there is a disproportional
increase in the plasma compared to the arithiasites that can lead to physiological anemia of
pregnancy. The higher blood volume is precipitated by an increase in circulating aldosterone
which promotes water retention in the kidneys and increased bone marrow RBC production and
reticulosites being released due to the higher maternal erythropoietin levels. Due to all of these
increases, it is not uncommon to hear of systolic ejection murmur. Although both systolic and
diastolic pressures levels decline slightly during pregnancy they reach their pregnant levels by
approx. 36 weeks. Venous pressure increases in a lot of part of pregnancy in the lower extremities
to venous congestions in form of varicose veins, hemorroids and dependant edema.
‐ Respiratory: Although the respiratory rate remains unchanged, tidal volume and resting minute
ventilation increases whereas the functional residual capacity and the residual volume are
decreased as the uterus elevated the diaphragm.
‐ GI: Reflux symptoms or heart burn affects anywhere from 30‐80 % of preg women, related more
towards the relaxed lower esophageal spincter, this is partly because of the increase estrogen and
progesterone, and partly because of increase in abdominal pressure as the pregnancy progresses.
Decreased stomach and intestinal motility occurs allowing for greater absorption of nutrients but
can also lead to constipation. The enlarged gallbladder during pregnancy contracts slower and this
can limit its ability to empty completely this can lead to biostasis increasing the risk of gall stones
forming causing cholestasis
‐ Renal: During pregnancy, the kidneys can increase in length and weight and there can be an
increased volume in their renal pelvis with dilated renal calysis. Ureters can also dilate, increasing
the urine volume and predispose UTIs. Due to the increased renal blood flow and glomerular
filtration rates, small amounts of the physiological glucose urea and protein urea can occur.
However the urine is evaluated each antenatal visit for the presence and amount of protein and
glucose. Increasing amount above the usual baseline requires further evaluation.
‐ Skin: stiae or stretch marks are common in 50% of women, often developing in the abdomen,
breasts and thighs in late in the second trimester. Hyperpigmentation occurs in up to 90% of the
women and is more noticeable with the darker complexions. The linea nigra is a hyperpigmented
line on the abdomen and the chloasma or mask of pregnancy are irregular patches of different 16
sizes on the face and or neck. The hyperpigmentation is attributed to the higher levels of the
melanocytes stimulating hormone, estrogen and progesterone, which all have properties to
stimulate melanocyte to produce melanin.
‐ Infertility is defines as failure for a couple to conceive after 1 year of unprotected intercourse. If
the woman is over 35 it is a 6 month period of time.
‐ The trends and causes of infertility in Canada are poorly understood and defined until the late
1900 and early 2000s. Much of the info was based on conjecture and inference.
‐ The prevalence in Canada in 2001 was about 8.5% when going by the definition of 1 year of
trying. Which translated to approx. 250 000 infertile couples at the time.
‐ Due to the paucity of data, before the century, it is difficult to comment on the trends of infertility
but there are few misconceptions that the prevalence is increasing. This has been attributed to
the thoughts that couples are seeking out medical intervention for infertility sooner possibly due
to the increased availability of treatments, medications, and specialists trained in the area. Or
that the total number of infertile couples has increased due to the baby boom era coming of
reproductive age or that ppl are talking more openly about their challenges in conceiving.
‐ We can comment on the trends in the US where it has been shown that the American rate of
10.2% has not changed from the 1965 data to present data.
‐ When investigated the causes can be attributed as female in 40% of the cases, male in 30‐40% of
cases, unknown in 10‐20 % of cases and in a small % it is a couple issue. Being that neither alone
have an issue but together there is a problem.
‐ Female issues can be hormonal such as ovulatory disorders: PCOS where there is an excessive
amount of male hormones in the woman causing ovulatory issues and some imbalances that can
cause recurrent miscarriages. Endometriosis and Pelvic Inflammatory Disease can lead to fallopian
tube occlusion. Congenital anomalies in the female genital tract may also be an issue.
‐ Noting under the modifiable risk, age, weight, exercise.
‐ Male factors can be because of sperm quality, quantity, motility or shape or due to sexual
‐ Part of the work up for an infetile couple is to do a semen analysis which looks at the shape,
movement, number of sperm, in a recent collected ejaculate sample after 3 days of abstinence.
‐ Stressors, smoking, alcohol, tobacco and substance use and abuse may also affect wither partner.
‐ For the unexplained causes, newer researchers are focusing on the connections between the
immune and reproductive system. Mainly that females have a more reactive immune system than
males for immediate infection protection. But also, this hyper‐reactivity can lead to increase
female autoimmunity development of anti‐sperm antibodies, both impacting fertility and/or
‐ Ovulation requires many factors to be working together in a normal f