What is Infertility?
Infertility is diagnosed when a couple does not get pregnant after one year of regular, unprotected intercourse. Primary infertility is the term describing couples who have never conceieved. Secondary infertility is the term used when a couple has achieved pregnancy previously regardless of whether the pregnancy was carried to term or not. 30% of infertile women are primary infertile while 70% have had one or more pregnancies previously. 8-10% of women between the ages of 15-44 will have difficulty getting pregnant. These numbers can vary between different cultures. It is the responsibility of the infertility specialitst to diagnose and inform the patient throroughly about their chances of conceiving. Particularly among women over the age of 35, or women who have been tested to have decreased chance of getting pregnant should be advised of ways to speed up the process.
What are pregnancy rates per menstrual cycle?
The first day of menstrual bleeding is designated as "day 1" of the menstrual cycle. If we look at 100 average fertile couples with a prior pregnancy who time intercourse in relation to ovulation, we’ll find that 20-25 of those couples have a positive pregnancy test. One month later 15-20 more couples will get pregnant and, in theory, at the end of 4 months all 100 couples should be pregnant. In reality %85-90 of these women become pregnant at the end of the year. It is generally accepted that a couple whose chances of conceiving are lower than 20-25% are diagnosed as infertile. When a couple has a 5% chance of getting pregnant each month, even if they time intercourse according to ovulation, their chance of conceiving at the end of one year is 60%.
What leads to pregnancy?
A conventional pregnancy results when sperm (male) and ovum/egg (female) meet inside a woman’s reproductive tract. At around the midpoint of the menstrual cycle (in a 28day cycle, this is between the 14th-16th day), ovulation occurs and an egg is discharged into the fallopian tubes. The egg can be viable for 12-48 hours during which time the sperm must reach the ovum. There must be viable sperm in the female reproductive tract which can survive for 3-8 days to achieve pregnancy. Ideally during the ovulation period, there should be intercourse every two days to ensure the presence of live sperm to maximize the chances of pregnancy in a given month. Couples who have begun infertility treatment should have a full evaluation of their sexual habits and should be encouraged to have intercourse at an optimal rate of every two days at around the time of ovulation.
These conditions must be met for pregnancy to occur:
- normal uterus and unblocked fallopian tubes
- formation of an egg
- sperm must enter the female reproductive tract and be able to remain viable until the egg has matured and is discharged into the tubes
- sperm must be capable of fertilizing an ovum
- the fertilized egg must reach uterine cavity
- the lining of the uterine, called the endometrium must have the necessary qualities for the fertilized ovum to implant
Types of infertility
Infertility types are categorized based on the presence or absence of the elements listed above.
Tubal Factor: The woman’s Fallopian tubes are either blocked or adhered to tissue around it. This makes it impossible for the sperm to fertilize the egg or for the fertilized egg to migrate to the uterus. Pregnancy rarely occurs and if does, chances of having an ectopic pregnancy are high.
Male factor: The sperm quality may be low. The sperm may be unable to fertilize the egg or have a short lifespan in the female reproductive tract.
Endometriosis: A condition where the tissue that should be found only in the uterus , is found in other areas such as in the abdomen, surface of the ovaries, sometimes even adhered to the intestines. By causing severe adhesions in the Fallopian tubes, the ovaries or the uterus, or in some cases immunological problems, endometriosis might lead to infertility.