However, there are exceptions, and they include the following:

If you are 35 years old, you should see a fertility specialist after 6 months of unsuccessful conception. If you are over 38, you should visit fertility specialist as soon as you start planning your pregnancy, because fertility between 38 and 40 declines significantly.

If you have been diagnosed with pelvic inflammatory disease, you should visit fertility specialist. Pelvic inflammatory disease is quite common, but a serious complication of some sexually transmitted diseases, especially Chlamydia and gonorrhea, and pelvic inflammatory disease can cause a damage to the fallopian tubes, uterus and ovaries, and can lead to serious consequences such as infertility, ectopic pregnancy, ectopic pregnancy and chronic pelvic pain. Or,   if you have had a positive test for chlamydia or gonorrhoea, both of which can block the fallopian tubes.

You should visit fertility specialist if you have been diagnosed with polycystic ovarian syndrome, or if you have irregular periods. You should also visit fertility specialist if you have been diagnosed with endometriosis.

You should also seek medical attention, if you have had previous ectopic pregnancy or one that resulted in one of your fallopian tubes removed.

If you had an appendicitis or abdominal surgery, that caused scarring or blocked fallopian tubes.

However, if you are a man, you should visit fertility specialist if you had a testicle infection, if you were treated for gonorrhea which can block tubes that carry sperm, or if you have problems getting or keeping an erection. You should also visit fertility specialist if your job involves radiation or a contact with chemicals.

There are also specific diseases that need special attention, such as previous cancer treatments, HIV, hepatitis B or C, and disease where there is a high risk of passing a gene to an embryo. These diseases include muscular dystrophy, cystic fibrosis or haemophilia, caused by a single faulty gene.

In cases of HIV, hepatitis B, C, muscular dystrophy, cystic fibrosis or haemophilia an embryos created by IVF can be screened by pre-implantation genetic diagnosis (PGD) before being placed in the womb.

As said above, numerous medical studies have proved that woman’s fertility dramatically decreases after age 35, since every woman is born with the unique supply of eggs during her lifetime until they stop producing them in menopause, while the effect on male fertility is only minimal, and men produce continuously sperm throughout their lives.

Woman has the most fertile eggs in her teens until her late 20’s. When woman reaches 30’s her eggs have a potential of fertilization, but it is decreased.  Reason for this is chromosomal injuries that are much more common with increased woman’s age.

Additionally, age is also related to increased number of miscarriages, especially when approaching the age of 40. This problem is mostly related to chromosomes and cellular machinery of eggs, there is little it can be done to turn back this biological clock.

For example, in woman younger than the ‘critical age’ of 35 the majority of ovulated eggs have normal composition of chromosomes, but as woman gets older than 35, the increasing number of her eggs get abnormal with the main reason lying in the natural process of aging when egg quality and quantity declines.

The causes of secondary infertility are often the same as the causes of primary infertility. However, since couples usually wait few years before conceiving second child, the most common cause for secondary infertility could be age-related. Quality of a woman’s eggs as well as man’s sperm declines as they grow older. It’s suggested that women over 35 years who are trying to conceive for six months without success, consult their doctor.
Other possible reasons for secondary infertility include various diseases in the man or woman, both diagnosed and underlying. Possible reasons for secondary infertility could be decreased sperm count in men due to age, lifestyle, poor diet, smoking, etc. Woman could suffer from ovulation problems, polycystic ovarian syndrome (PCOS), hormonal disorders, endometriosis, pelvic inflammatory disease or previous ectopic pregnancy that all could be reasons for secondary infertility. Large weight gain or loss in both men and women could be major reason for inability to conceive second child, especially in women because weight gain and obesity could postpone ovulatory cycles. Sexually transmitted diseases such as Chlamydia could also cause secondary infertility.

Diagnosing infertility requires a few tests, which is the first step in treatment. Even if you conceived your first child without delay, that doesn’t mean that you won’t have problems with second infertility. That’s why you shouldn’t delay visit to your doctor. With age being a main factor for infertility, the earlier partners begin treatment, the better chance they have of becoming pregnant. If partners are not able to conceive after having a year of unprotected sex, your first step should be to consult with your doctor. But if you are over the age of 35, you should wait only six months before talking to your doctor.

This form of infertility can be very difficult to deal with emotionally. It causes a lot of stress, since many couples don’t expect to have difficulty conceiving again, especially if the first pregnancy went well without any problems or obstacles. Parents unable to have second child might feel as they are letting down their first child by not providing a sister or brother. At the same time, they can feel guilty that the first child is somehow not enough, being the constant reminder of the loss. Also the time and emotional commitment that parents involve in infertility treatment, can make them think they’re not as committed to their first child as they would like. Infertility can destroy your relationship and relationship with your first child if you allow it. Parents shouldn’t waste their time feeling unhappy and desperate. They should dedicate all time they have to their first child.