L30 Assisted Reproduction

when is a pregnancy actually counted from

the last period, this means you’re about two weeks pregnant by the time you’re pregnant

what happens to the follicle once the egg is released

it turns into the corpus luteum

other than thickening, what other changes occur to the endometrium as it starts getting ready to support a pregnancy

glands expand and start secreting uterine milk (histotroph), which can nourish a potential embryo before it has fully connected to the mothers blood supply

what causes glands to expand and start secreting histotroph in the endometrium

progesterone

describe how one dominant follicle is selected during each menstrual cycle

as oestrogen goes up, FSH goes down due to negative feedback, as the follicle gets larger, it does not need as much FSH to grow and is able to start growing using LH, this selects the one biggest follicle to mature each cycle

what happens towards the end of the menstrual cycle if pregnancy occurs

hCG signals to the corpus luteum and it does not die, the corpus luteum produces progesterone which helps maintain pregnancy, at 12 weeks, the corpus luteum dies but the placenta produces progesterone, thus maintaining the pregnancy

what does a pregnancy test measure

hCG

how does the body’s hormonal feedback system change from a normal cycle to a sustained pregnancy

KISS neurones fire in the hypothalamus, acting as the master switch, the hypothalamus releases GnRH, which tells the pituitary to activate, the pituitary sends FSH and LH to the ovaries (AMH ensures that too many eggs don’t try to develop at once, the developing egg follicle releases oestrogen and inhibin, these tell the pituitary to lower FSH, once oestrogen levels get high enough, this causes a spike in LH, causing ovulation, the corpus luteum secretes progesterone to thicken the endometrium, if conception occurs, the new embryo releases hCG, high progesterone and oestrogen provide constant negative feedback to the hypothalamus and pituitary, meaning no new eggs are released while you are already pregnant, prolactin levels rise to prepare for lactation, eventually the placenta takes over the role as the main progesterone producer

what is the natural fertility of humans

22%

what does a fertility of 22% mean for humans

per month, about 22% of couples who are trying for a child will get pregnant

approximately how many couples experience fertility problems at some point

about 1 in 6

how long should you generally try to have a child before you visit a fertility clinic

1-1.5 years

with normal fertility, what percentage of couples successfully get pregnant within 12 months

87%

what are two general tests that are done when someone comes into a fertility clinic

ensure that they have the rubella vaccine, as getting rubella during pregnancy can cause foetal abnormalities, do a swab to ensure no STDs such as chlamydia or gonorrhea

how many sperm should there be in each ml of ejaculate

at least 15 million

how many sperm should there be in one ejaculation

at least 40 million

what percentage of sperm in the ejaculate should be healthy

at least 40%

what percentage of the sperm in a sample are expected to look normal

only around 4%

what is a test of tubal patency

dye is put through the uterus to ensure tubes are open

from what age onwards does fertility decline in women

from 36 onwards

what are the five main categories that cause infertility

ovulatory issue, blockage in the tube, problem with sperm, more than one problem, unexplained

approximately how many cases of infertility are caused by issues with sperm

about 1/3

what is the course of action for fertility treatments if there is sperm production

IVF

what is no sperm production known was

isospermia

what are the three main causes of isospermia

testes do not have the capacity to produce sperm, hormones are low (or FSH may be too high), blocked or absent vas deferens

what is hydrosalpinges

fluid can drip into the uterus making the environment acidic, meaning there is only about a 50% chance of IVF working

during the maturation of multiple eggs for IVF, what is one of the main problems

the “egg release” signal comes before the egg is actually ready

how do you get around the early “egg release” signal when developing multiple follicles

by using a GnRH antagonist or agonist, as both work to prevent the LH surge

after the artificial LH surge is given, how long after must the eggs be harvested

almost exactly 35 hours after

what is the process of preparing the egg for IVF

all cumulus cells are removed, a sperm is selected and injected into the egg (ICSI)

how is the early embryo inserted into the uterus

embryo is inserted into the uterus through a tube, progesterone is then given until there is a positive pregnancy test

what is the maximum age that the Scottish government will treat with IVF

42 years old